|
RIGS_ID |
Grid_reference |
Locality |
Feature |
Stratigraphy |
Geomorphology |
Description |
Access |
LGS (formerly known as RIGS) |
InterestCategory |
| 0002 |
SO 279 959 |
Spywood and
Aldress Dingle |
Stream and tracks |
Ordovician (Upper): various members. |
These dingles are two of a number of steep gorges in the area that are
associated with the River Camlad and its small tributaries. |
The majority of this site is not accessible by public paths or even by
forest tracks. At SO 276 957 where the footpath from 'The
Rock' goes steeply down a track to the stream there is an interesting
outcrop of steeply dipping beds. These are of the Aldress
Shale Formation according to the BGS Shelve Area map. These dip at
about 80° to the NW. This exposure consists of undulating beds of
shales with more massive material above. This exposure is about 3 m
high by 7 m. If this track is followed to the stream another outcrop
can be seen on the other side of the river. There is no way over the
stream but the steeply dipping beds can be clearly seen from this
distance. Another exposure was found at SO 278 959. This is in the
track; again just above the stream and is about 1 m high by 10 m and
showed the same sort of shaley material. There were a few other small
outcrops visible along the stream banks and tracks but there was always
an access problem. According to ref.1 the exposures are fossiliferous
and particularly rich in graptolites with a number of species of
graptolites and trilobites being defined from collections from here. The
majority of the land within the SSSI boundary is Aldress Shale
Formation. The section only really appears on the map to be up the
eastwards trending valley along which there are no footpaths. |
There is a big access problem in this area since there are few
footpaths. None appear to be way-marked on
the ground. One was missing altogether with no way over barbed wire
fences and no path through the wood. The owner is very keen on telling
people where they can't go but not on where they can go. There appear
to be few forest tracks along the dingles; so even if permission was
sought to leave the footpaths it would be difficult to travel up the
streams to find any outcrops especially as they are all wooded. |
LGS Yes. Already designated as an SSSI |
Sedimentology/Stratigraphy |
| 0003 |
SO 565 871 |
Oak Dingle - Abdon |
Stream/brook |
Silurian / Devonian boundary (ref.1); Devonian: Ditton Series (BGS Sheet
166). |
This is a small dingle cut into the undulating ground between the steep
slopes of the Brown Clee Hills and the flat land of the valley of the
River Corve. The high ground to the W of the dingle (that can be
reached by a footpath that crosses the dingle) allows a view of the
countryside from where these features can be appreciated. |
Faunal changes through time can be recognised and by comparison with
sections of similar age further north a faunal variation controlled by
environmental factors can be studied. This is the type locality for a
recently discovered species of acanthodian Cephalaspid and an early
arthrodire and so is a key locality for studies of fish fauna in the
Silurian-Devonian boundary beds. The N/S trending dingle provides an
easily traversable way up the stream. The stream flows over many bedding
planes which form the flat bed of the stream. There are some exposures
in the bank at intervals up the stream that would allow study or
possible collection of fish fossils. The ones near the bottom of the
dingle were of flaggy and massive red sandstone. The bedding planes in
the stream bed did not appear to reveal any fossils to my untrained eye.
The SSSI also includes a short section of the mainly E/W trending stream
at the bottom of the dingle on the other side of the road. There are few
exposures in this section except for the bedding planes in the stream
that create pools and waterfalls. This makes this section more difficult
to study at periods of high flow. |
From the Corve Dale road (B4368) follow a series of minor roads to the
village of Tugford. The SSSI site is on either side of the road between
Tugford and Abdon. The wooded dingle is easily identified on the LHS of
the road where the road crosses a bridge. There is no public access
along the stream but it is easy to walk up the stream and there is easy
access to the stream from the road. There is room to park just E of the
bridge. High flow rates may make this site less accessible and harder to
study. Obviously permission should be sought from the owners especially
for groups. |
LGS Yes. This is already an SSSI and appears to be in reasonable
condition. Due to the nature of the beds the fossils are not obvious so
the benefit to younger students may not be great. This is a type
locality. There is plenty of material for study by researchers and the
more experienced. |
Fossils and Sedimentology/Stratigraphy |
| 0006 |
SO 396 876 |
Hillend Quarry
/ Hillend Farm (W) - Lydbury North. |
Track/roadside |
Silurian: Llandovery Series (Lower): Pentamerus Beds. |
This site below the steep S end of the Longmynd and just above the
meandering River Onny. |
This site consists of a lot of fine talus and
some larger pieces (up to 50 mm across) which are still revealing a lot
of fossils and which are from the Pentamerus Beds. To the right of the
exposure there is some interesting weathering of iron-rich rocks. The
disused excavations behind the fence do not appear to show any more
exposures of rock as they are all grassed over and this is private land. |
This is a road side site so access is no problem. Park by the gate to
the E in dry weather or in the lay-by about 600m SW where there is space
for a few cars without any danger of blocking access. The exposure is
clearly seen on the N side of the road. |
LGS Yes. This site is an SSSI and a LGS. It is an easily accessible
site showing a clearly identifiable lithology and has plenty of loose
material to study. As it is still revealing fossils and is still
accessible it should remain as a LGS. It was designated as a LGS to
help ensure a continuance of its role as a good introductory locality as
well as exposing a component of the Silurian section along the A489
between Hillend and the Cwm Head road. |
Sedimentology/Stratigraphy |
| 0007 |
SO 425 854 |
Onny River
Section |
Cliff |
Unconformity between Ordovician (Caradoc: Onny Shales) and Silurian
(Upper Llandovery: Hughley Shales) |
River cliff of meandering Onny River. |
This is the classic Ordovician-Silurian unconformity. It can be detected
in the cliff on the N bank by a subtle change of dip from 22°SE to 18°SE
with the Hughly Shales overlapping the Onny Shales. This site remains
quite clear of vegetation and access and viewing is easy. It is not
possible to cross the river except at very low flows. This is good as it
means the faces are less likely to be hammered. Continued erosion by the
river at times of high flows will remove some material but this should
keep the face 'clean'. Trilobites are sometimes found in the river at
low flows. There is a lot of loose material in the form of river worn
pebbles of various ages that have been brought down-stream. The SSSI
covers the river and its banks from 426852 to 422854. This area includes
outcrops which are the type-sections of the Actonian and Onnian Stages
of the Ordovician (ref.1). It is unclear where the Actonian stage
finishes and that of the Onnian starts and this junction may only be
visible in the river bed at times of low flow. |
This is found along the Onny Valley walk which is a permissive footpath
allowed by the owners of Cheney Longville Estate. The trial runs from a
car park over the railway bridge off the A49 up the Cheney Longville
road. It continues along the river and old railway as far as Glenburrell. |
LGS Yes. This is an SSSI for its geological importance therefore it
ought to be designated as a LGS. It should be designated as part of a
larger site encompassing the whole of the river as outlined in the
attached note (Word file name:- Onny Valley Area). |
Sedimentology/Stratigraphy |
| 0010 |
SO 525 779 |
Tar Grove
Quarry and Tar Grove Dingle |
Quarry (disused) |
Lower Old Red Sandstone: Ditton Series. |
Quarry cut into hillside and stream cutting down through hill. |
The present SSSI designation is just for the quarry. This is becoming
very vegetated with rhododendrons and small trees making it difficult to
reach the faces that are exposed. The main exposure is to the E on the
back wall. There is another much smaller one just at the left of the
entrance; the beds dip NNW. It shows massive red sandstone separated by
thinner bands of fine sst and micaceous sltst some of which have
weathered to a green 'chalky' material. One face trending NNW/SSE has a
thin covering of calcite. About 20 m of beds are exposed and the quarry
is about 50 m across. The stream sites described in ref.1 are not really
accessible as the banks are steep and vegetated. There are no obvious
exposures in the stream either side of the track except for occasional
small waterfalls. This quarry yields one of the most diverse known
assemblages of fossil plants of Gedinnian (Lower Devonian) age
consisting of about 20 species of algae nematophytes (primitive
non-vascular plants) and primitive vascular plants. The specimens are
unusually well preserved and yield information on the cell structure of
the plants. The flora is the subject of much active research and is also
of historical interest since it was from here that in 1937 W H Lang
described specimens which until the discovery of similar material in the
Ludlow beds of South Wales was the oldest indisputable evidence of a
vascular plant. Thus from the point of view of both its historical
interest and its present research potential this site is of great
international importance. |
These sites are on the Downton Hall Estate (along the southernmost
drive) and are not on a public path. |
LGS Yes. Already an SSSI for the importance of its plant fossils (ref.
2) but access is only with permission from the owner (Mr Wiggin at
Downton Hall) and is probably best kept to research. |
Fossils |
| 0011 |
SO 519 897 to SO 521 893 |
Upper Millichope - Munslow |
Stream/brook |
Silurian: Lower Ludlow: Lower and Middle Elton Formation (ref.1). |
This site is on the NW slope of the NE/SW trending valley of the River
Corve. The other side of this valley is partly made up of the Brown
Clee Hills. The stream eventually runs into the River Corve. |
The reason for notification as an SSSI is as follows: This site shows a
long stratigraphical section through the Lower Ludlow Lower and Middle
Elton Formation with a Lobograptus scanicus graptolite fauna and an
acritarch microflora typical of the Tylotopalla pyramidale biozone. The
fauna and flora suggest deposition of the calcareous siltstones here in
comparatively deep water conditions. The macrofauna present consists of
well-preserved graptolites trilobites and brachiopods. There are
outcrops in the banks of the stream at intervals for several hundred
meters up the stream from the bridge by the footpath (see below). These
are continually eroding so provide a plentiful supply of loose material
in which to find the fossils mentioned. The trilobites are the most
obvious and there are still lots of specimens to be found in various
states of preservation. As usual they are dislocated and there appear
to be far more pygidia than cephalons. Some separated compound eyes can
also be found. Because of the abundant material there is NO NEED TO
HAMMER at the exposures. More material can be found under the rotting
leaves. Other fossils found on this visit included gastropods (Loxonema)
the occasional graptolite small brachiopods and bivalves as well as the
Dalmanites trilobites. The best fossil collecting exposures appeared to
be between the first two bridges. This is the most accessible part of
the stream and the rock appeared to be more fossiliferous here. Above
the next bridge upstream the stream has created more of a gorge which
was impassable at the level of flow on this visit. Because of the
steepness of the banks it is also difficult to reach the stream level
from the road at most places above this bridge. There are a few places
where access is possible but these are quite limited and the rock at the
higher levels did not reveal as many fossils. The top of the site looses
its interest altogether with no exposures and no 'beaches' on which to
find loose material. The rock is siltstone which gets less green and
more calcareous upstream. |
Upper Millichope is on a minor road between the Corve Dale road (B4368)
and Wall under Haywood (on the B4371). It is probably best to traverse
the stream in an upstream direction as the bottom of the site is more
interesting and easier to traverse. Enter the stream just upstream of
the footpath over a bridge opposite a farm entrance. By walking in the
stream it is possible to reach the next bridge upstream with very little
problem. At low flow it may be possible to follow the stream further. |
LGS Yes. This is also an SSSI. It has obvious fossils in abundant
loose material which are suitable for use by all groups of all abilities
and interests. It would be suitable for school groups or researchers.
The site is quite open and easily accessible. |
Fossils |
| 0012 |
SO 519 742 |
Temeside |
Bank |
Silurian: Temeside Shales Formation (Pridoli Stage) |
Exposure in the south bank of the River Teme just downstream of Casemill
Weir; directly opposite the Case Mill. |
A
small section of river cliff running along the southern bank of the
River Teme. The exposed rocks show a channel-fill within the mudstone
and siltstone sequence of the Temeside Shales Formation. This unusual
sedimentary feature in these Silurian-aged rocks contains a diverse
assemblage of fossil ‘fish’ fragments and larger specimens; which are
extremely rare elsewhere. The cephalaspids Thyestes salteri and
Hemicyclaspis murchisoni have been recorded from here; as well as
several types of acanthodian spine and thelodonts. The site has received
little collecting attention in the past; but recently heterostracan
fragments; new species of acanthodian; and a graptolite have all been
found here. This is a unique site for vertebrate studies with much
potential for future research. |
Access is down steep wooded bank from edge of field leading from St
Giles Church car park; Ludford; on private land. |
LGS Yes. As this is already an SSSI it should be a LGS. |
Fossils |
| 0013 |
SO 426 807 |
View Edge
Quarries |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group (BGS SO48; Craven Arms). |
These quarries have been cut into the top of a prominent scarp created
by the resistant Aymestry Beds above the softer Lower Ludlow Shales. |
As
per previous report. Whilst not as spectacular as the near by site at
Brandhill this quarry has very clear features and a greater abundance of
fossiliferous material. This site has remained quite clear with only a
few stunted trees on a few ledges. The faces are mostly very accessible
and whilst some are obscured totally there is still plenty to see.
There is plenty of loose material containing large shell fragments
including what looks like a recently hammered area. The shells are also
clearly visible at certain points within the rock. |
The quarry is accessed via a gate about 200 m SE of Viewedge Farm. Park
in the gateway or elsewhere along the lane. There is no public right of
way to the faces but there is permissive access negotiated by the AONB;
large parties should seek prior permission from the farm at the top of
the hill. |
LGS Yes. This is an SSSI for their distinctive shell banks of the large
strophomonid brachiopod Conchidium knightii. This is a shallow-water
fauna which is characteristic of the Aymestry Limestone Group in this
area. |
Fossils |
| 0014 |
SO 337 990 |
Shelve Church |
Bank |
Ordovician: Mytton Flags |
Bank surrounding church yard. |
This site is meant to be a famous exposure of Mytton Flags with fossils
from deep and shallow marine environments. However the site is now
overgrown with a pool created on some of the site that is marked as SSSI
on the Map I have been give (file reference S/S/36). It is mostly
covered in grass and only one patch of rock shows through (which may be
in-situ or part of a wall). There is no clear exposure of rock so
unless this site can be uncovered I suggest it will loose its SSSI
status and should not be designated as a LGS site. I guess its only
use at present is for research purposes by those who are willing to
clear vegetation. |
The church is on the N side of the road in the village of Shelve. There
is room to park just in front of the church gates. |
LGS Yes. Already designated as an SSSI |
Fossils |
| 0019 |
SJ 318 024 to 317 013 |
Betton Dingle |
Stream/brook |
Ordovician: Llanvirn Series: Stapeley Volcanics to Betton Beds (ref.1). |
This is one of several steep sided narrow valley running N off an area
of higher ground into the wide and fairly flat NE/SW trending Rea Brook
valley. |
This stream is very vegetated with many fallen trees over the stream and
debris causing pools and waterfalls that would be dangerous to wade
through. This in combination with the very steep sides makes this
stream virtually impossible to traverse for any distance in either
direction. On this visit an attempt was made to walk downstream from
Lyde to Betton. This was not really possible. Even on the bits that
were reached there was no useful exposures. The only exposed rock are
the bedding surfaces that make up the stream bed and create some of the
rapids and waterfalls. The loose material in the stream was of a
variety of lithologies and was very worn indicating that it is likely to
have come from upstream and does not relate to the beds in the stream at
the point at which the pieces are found. I did not find fossils in any
of the material. Upstream of the road did not appear to be any more
accessible and there was no obvious outcrops in the stream. There is a
small exposure at a track junction just off the road and over a cattle
grid which shows rusty; very friable beds. There was also some material
exposed in the track that follows the stream. I did not find any
fossils in any of the loose material here. |
The dingle goes S from Betton Farm. There is no public access and to
walk along the stream appears to be to dangerous to recommend. Part of
the SSSI site is a Shropshire Wildlife Site. |
LGS Yes. Already designated as an SSSI |
Sedimentology/Stratigraphy |
| 21 |
SO 602 758 to 603 755 |
Cornbrook Dingle - Coreley |
Stream/brook |
Carboniferous: Cornbrook Sandstone Formation. |
Small stream running down the side of Clee Hill |
There are a number of exposures along this small narrow (<1 m wide)
stream and its steep banks from where it goes under the A4117 to the
waterfall downstream of the track at SO603755. These show very coarse
sandstones and conglomerates which are usually poorly sorted and
sub-rounded. The conglomerates contain mostly quartz clasts but also
other lithologies too. The coarsest conglomerates have quartz clasts of
up to 30 mm in the largest direction. In some beds the conglomerate
bands are of various grades; each one quite well sorted with the
intervening rock being medium-coarse sandstone. Most of the rock has
weathered to a rusty orange colour (probaly from acid minewtaer draining
the Coal Measures); this can be variable and appears as bands in some of
the beds. There are areas of calcite mineralisation seen as thin layers
(?slickensides) on some surfaces of the sandstone. At one point the
stream has created a deep gorge which is very difficult to walk down but
can be traversed around the top. A few outcrops are visible in the gorge
below. About 20 m below the track which the stream goes under there is a
series of waterfalls (the site of a former iron works). These show more
rust coloured sandstone. The first of the falls is the largest with a
drop of about 2.5 m (the site of a water wheel) and the second has a
drop of about 1 m. There is an exposure of rock on the E side of the
stream but again this is not accessible due to the steep sides of the
bank. According to ref.1. this site is an SSSI as one of the best
exposures (and the type-locality) of the Cornbrook Sandstone Formation
(the lowest deposit of Pennsylvanian age). It shows how sediments were
deposited on St. George's Land. Good fossil fauna has been found here
(especially plants). Coal mine drainage adit daylights here;
iron-stained acid minewater can e seen discharging on the left bank
above the track. |
Park on the A4117 opposite the cottage on the N side of the road. The
stream goes down hill from the corner of the road and can be paddled or
followed most of the way. Alternatively park on the track that leaves
the A4117 at SO608758 where it crosses the stream and follow the stream
up the hill. Other facilities can be found at Clee Hill village 1 km to
the west. |
LGS Yes. This is also an SSSI. Although access is good and there is
plenty of material to work with the streamway itslef is steep and
difficult to follow. The location is the type section for the Cornbrook
Sandstone Formation (some have correlated this with the Carboniferous
Millstone Grit) containing good sedimentary features. An iron smelter
was formerly located here. Coal mine drainage adit daylights here. |
Petrology and Stratigraphy |
| 0022 |
SJ 342 015 to 357 021 |
Hope Valley - Worthen |
Quarry |
Ordovician (Hope Shales) and Silurian (Llandovery Venusbank Formation). |
Quarry; stream and roadside exposures along the bottom of Hope Valley. |
Hope Mill Quarry ( 355021) (as incorporated in the SSSI) used to show
Ord/Sil unconformity. Recent woodland clearance work by the SWT has
apparently destroyed what remained of this outcrop. The quarry still
remains and shows massive sandstones and shales of Llandovery series.
These show cross bedding and bioturbation; with some loose material
containing fossils. The stream bed on the opposite side of the road
shows steeply dipping Ordovician Hope Shales. The stream is accessible
in places but without wellies it can not be walked to see if it reveals
a contact with the Silurian at any point. On the LHS (S) of the quarry
there is a spur which descends to the road. At its base a very small
exposure was excavated to see if this was Hope Shales. It appeared to
be dipping east; and was darker than the obviously Silurian rocks above;
but was very broken up. This would need to be excavated further to see
if it was Hope Shales. Also included in this site is the quarry by the
bus stop in Hope village. This shows good folding of the Silurian rocks.
Smaller exposures of folded Silurian rocks can be seen on the RHS of the
road when travelling south. |
The Quarry is situated on the W side of the Bishop's Castle to
Shrewsbury road just N of the village of Hope. It is best to park in SWT
carpark or small lay-by; then walk down the road (N) to the quarry. The
road is twisty and without a footpath; therefore quite dangerous. The
stream is accessible through holes in the hedge in a number of places
but its banks are also often steep. The bus stop site has a lay-by
right in-front of it. |
LGS Yes. Already an SSSI? Should be designated if the unconformity can
be uncovered. Designated for the importance of the unconformity between
Ordovician Hope Shales and the Silurian Venusbank Formation. The Hope
Shales in the Lower Llanvirnian include their type section. Boundary
includes the Hope Valley SSSI. |
Sedimentology/Stratigraphy |
| 0026 |
SJ 375 023 |
Snailbeach Mine |
Mine/adit |
Ordovician: Arenig Series: Mytton Flags (BGS 1: 25000 Shelve Area). |
This site is at the foot of some very steep slopes that lead up onto the
NE/SW trending ridge made by the more resistant Stiperstones Quartzite
over the softer Mytton Flags to the W and Habberley Shales to the E.
The view point on the heritage trail provides excellent views to the N
and round to the SW. |
This was the main mine of the Stiperstones mining district. Small scale
operations continued after the flooding of the lower levels until 1955.
This last mining was for barytes used in the paper and paint industry.
The lower level mining was for barytes; lead and zinc. This site was
deemed unsafe for the local population due to the amount of spoil that
was left from the mining operations. In 1995 a reclamation scheme was
completed that has landscaped most of the spoil tips. There is also a
restoration scheme underway to make safe the remaining buildings and
encourage interested visitors. There is now a heritage trail around the
site. This scheme has included a patch of spoil to be left to be 'picked
over' by geologists etc. This is what is described as the 'Rock Store'
on the interpretive panels that are around the site. This is an area
about 20 m in diameter of exposed spoil. There are still minerals to be
found but; as with all these tips; the most common are calcite; barites
and quartz. There is more material visible in a part of the tip that
has remained to make a view point over the site. However this is likely
to be left to become vegetated over time. This also contains the above
minerals but the average size of the loose material is much smaller.
There is no other exposed rock or spoil over the rest of the site. |
This site is in the village of Snailbeach. There is a car park by the
toilets and village hall that visitors are requested to use. |
LGS Yes. Spoil has been left for the specific interest of geologists.
Although it is smaller than some of the other tips in the area it is put
in context by the rest of the buildings etc of the heritage trail so a
better understanding can be gained of the importance of the geology to
the area and how it was dealt with. |
Mineralogy/Petrology |
| 0031 |
SO 290 995 |
Kinton Quarry |
Quarry |
Ordovician: pre-Lower Llandovery Caradocian dolerite intrusion (ref.1). |
nothing particular. |
This quarry still clearly shows the columnar jointing that is referred
to in ref.1. It is best to the LHS of the quarry where the columns can
be seen to curve slightly. The whole of this quarry has been cut into
the dolerite and there looks like there has been some fairly recent
excavation; probably by the farmer for hardcore. Apart from the
columnar jointing there is not much else to note. |
This can be reached by taking the partly unfenced farm track SW from
Rorrington. Or a footpath NW from opposite Middleton Hall Farm
(SO297991). The quarry is on the N side of the track just by a cattle
grid. It is fenced off from the road but there is a gate. |
LGS Yes. This should be a LGS site as a good; clear example of
columnar jointing at a site that is easily accessible for groups of all
sizes. |
Mineralogy/Petrology |
| 0033 |
SO 297 758 |
Black Garn -
Chapel Lawn |
Quarry (disused) |
Silurian: Downtonian (Platyschisma beds according to the information on
the Favoured list). |
Quarry on the slopes of the steep side Caer Caradoc which is topped by a
hill fort. |
The LHS of the quarry shows a very impressive distortion due to movement
along a thrust plane. The beds have been clearly distorted into tight
folds. The lower set of these terminates next to the plane of
faulting. The distortion is of massive beds 30 to 120 mm thick with
fine laminated partings of a few cm. The beds appear to be competent
and have folded together. I found no fossils on this visit. The RHS of
the quarry is much more obscured (mainly by moss) but the beds appeared
to be unaffected by the faulting of the LHS. The adjacent stream section
is on private land with no public access. I could not see any exposures
of any size within the stream. There was one small exposure on the
upstream side of the road which showed beds of a few cm thick. As there
is no public access it is probably best to leave these exposures for
research use only. |
This site can be found on a small lane that leaves the A488 at Five
Turnings (1.5 km S of New Invention) between Clun and Knighton. The
site is on the E side of the road on a tight bend just E of the entrance
to Black Garn Farm. There is very little parking on the narrow lane but
there is a bit of verge at the point of the site. |
LGS Yes. This should be a LGS as a good and easily accessible example
of the effects of faulting / thrusting. The structures are very clear
and can be readily explained. |
Structure |
| 0038 |
SJ 314 024 |
Betton Wood
Farm |
Quarry (disused) |
Ordovician: Llandeilo Series: Meadowtown Beds (ref.1). |
This site is near the base of the valley side of the wide and flat NE/SW
trending Rea Brook valley area. |
This quarry consists mostly of one face. This is mostly massive
limestone. Water seeping through and over the rock has resulted in
calcareous deposits at the base of the face. Ref.1 states that the
limestone has been intruded by dolerite but this was not obvious. To
the left of the face the are thin beds of siltstone (<10 mm thick) which
have produced a lot of talus. This loose material is quite
fossiliferous with several fragments of trilobite pitted fringe
visible. Some of the pieces are dark and micaceous whilst others are a
paler mudstone. Some bioturbation is evident and there were a few
pieces of calcite. |
Ask permission at Betton Wood Farm. Take the track up the hill and to
the left along a sunken lane. The quarry is about 300 m from the farm
in a group of trees. |
LGS Yes. This should be a LGS as an example of the Meadowtown Beds
that can no longer be seen in Meadowtown Quarry. It also shows a
different aspect of the Meadowtown Beds to the quarry at SJ312013.
There is plenty of loose material and the site is large enough for good
sized groups. |
Sedimentology/Stratigraphy |
| 0040 |
SO 317 836 |
Withins Bury
Ditches; Clun (Brookbath) |
Track/roadside |
Silurian: Cefn Einion Formation; Platyschisma Beds and Downton Castle
Sandstone (ref.1). |
This track-side cutting is in a small valley on the side of the conical
shaped Sunny Hill from which there are good 360° views interpreted with
the aid of a toposcope. |
This site was described in ref.1 as being a 500 m long section showing
the above horizons with the Downton Bone Bed (equivalent to the Ludlow
Bone Bed) exposed in the banks of a steep ride. I found a good exposure
about 2 m by 30 m on the track-side where it bends around a valley.
This shows massively bedded fine; mica rich; sandstone with beds up to
15 m thick. Further down the track there is an amount of talus but no
in situ rock is exposed. It is possible that this did show rock at the
time that the reference was written. There is more exposure a few
metres up the track where a green way-marked footpath leaves the main
track. The making of the footpath has revealed purple shales which show
bioturbation on many of the loose pieces. One area looked like a badly
weathered lump of multiple shell fragments. Apart from that lump very
few fossils were seen. Despite looking quite hard I could not identify a
bed which could have been the bone bed. However the site is still a
good comparison to the more flaggy material of the CEF and the very
shaley flat bedding of the KC beds. In ref.1 fossils to be found
include Cyathaspis banksi; Sclerodus; Onchus and thelodonts. |
Park at the Forestry Commission car park for Bury Ditches and make your
way around the forest tracks. This site is where the green waymarked
walk crosses a hard-cored track. |
LGS Yes. This should be considered for designation in conjunction with
other sites in the area that show the different facies within the Ludlow
Series and the Lower Devonian (if this site does show Downton Castle
Sandstone). The value of the site would be increased further if the
Downton Bone Bed could be identified. |
Fossils and Sedimentology/Stratigraphy |
| 0043 |
SO 325 956 |
Tasker Quarry - More |
Quarry (disused) |
Ordovician: Llanvirn: Stapeley Volcanics Group and Stapeley Shales. |
Cut into hillside. |
Medium sized quarry showing massive interbedded shales; hard tuffs;
breccias and other pyroclastics. Some small faults. Fauna includes
trilobites and graptolites. (Ref.1.). |
It
is now fenced off but there is a stile over it. There is room for one
car to pull of the road in front of the quarry otherwise park in the
lane to Nind just to the south. |
LGS Yes. Designated to emphasise its geological significance as an
excellent example of sedimentary features which can be preserved within
volcanic sediments. |
Fossils and Sedimentology/Stratigraphy |
| 0045 |
SO 335 990 |
Shelve Farm |
Quarry (disused) |
Ordovician: Arenig Series: Mytton Flags. |
Quarry cut into bank. |
Abundant loose material from the Mytton Flags and the face is easily
accessible. Fossils were found in this material and there is a
bentonite band (ref.1.). Fossils previously found here include
trilobites; graptolites and gastropods. |
The farmer is quite willing to let people get at the site but permission
must be sought first at the house. Access is either through the
buildings or round the top of the farm. Park in the road; or at the
farm. |
LGS Yes. As the SSSI at Shelve Church (337990) is no longer visible
this is a good alternative. This quarry is now behind a relatively new
barn and has possibly been reworked in order to fit this building in.
Access is easy and there is abundant material. It is described on my
list as a 'classic locality'. |
Fossils |
| 0046 |
SO 368 987 |
Stiperstones (main ridge) |
Crag |
Ordovician: Arenig Series: Shelve Group: Stiperstones Quartzite. |
Frost shattered tors on long high NNE/SSW trending ridge formed by
resistant quartzite flanked by less resistant shales. |
This site comprises a series of frost shattered tors with classic 'stone
runs' (associated boulder screes that have formed stone stripes as a
result of solifluction). There are boulders of various sizes and
textures from conglomerate to fine quartzite. Some have quartz veins
running through them occasionally showing well formed quartz crystals.
There are good views from here across to Corndon Hill in the west and
down towards Linley in the south. It is also a very good point a which
to look north up the ridge where other tors can be seen on a good day. |
A
footpath climbs to the ridge from the Bog to Linley road from the large
car park at the southeast corner of the area. |
LGS Yes. The Stiperstones ridge is the best site in the country for
stone runs and displays well the variability of the Stiperstones
Quartzite from fine grained to conglomeratic together with evidence of
mineralisation in the form of quartz veins. |
Geomorphology/Landscape |
| 0047 |
SO 351 964 |
Stiperstones
(The Rock) |
Crag |
Ordovician: Arenig Series: Shelve Group: Stiperstones Quartzite. |
Frost shattered tor on long high NNE/SSW trending ridge formed by
resistant quartzite flanked by less resistant shales. |
This is one of a series of frost shattered tors which associated boulder
scree which outcrop on top of the Stiperstones ridge. There are
boulders of various sizes and textures from conglomerate to fine
quartzite. Some have quartz veins running through them; occasionally
showing well formed quartz crystals. There are good views from here
across to Corndon Hill in the west and down towards Linley in the
south. It is also a very good point a which to look north up the ridge
where other tors can be seen on a good day. |
A
short path leads directly to the rock from the Bog to Linley road.
There is no parking here so it is best to walk down the road from the
Nipstone car park about 1 km to the N. |
LGS Yes. This should be designated either on its own or as part of a
larger site which incorporated all of the Stiperstones ridge. Designated
for its display of the variability of the Stiperstones Quartzite from
fine grained to conglomeratic and evidence of mineralisation in the form
of quartz veins. The site is also a good view point from which to
appreciate the context of the Stiperstones ridge to the north. |
Geomorphology/Landscape |
| 0048 |
SO 352 764 |
Gripes Nest - Hopton |
Quarry (disused) |
Silurian: Bailey Hill Formation. |
Large quarry cut into the slope of a small valley separating Bedstone
Hill and Hopton Titterhill. |
This is quite a large site about 20 m high and 30 m wide. It is mostly
greenish grey micaceous siltstone but with calcareous nodules and some
bands of finely laminated pale or orange sandstone. There are several
slump features causing folds and changes of dip direction. The overall
dip is about 10°W. The central outcrop shows the slumping well with an
obvious large scale change in dip and folding picked out by light and
dark banding. A large nodule in the exposure to the left and above the
central outcrop has caused deformation of the beds beneath. Uneven
laminations could be seen on a small scale in many of the loose pieces
that cover the lower slopes in many parts. Few fossils were found but
there was a lot of bioturbation evident on the surfaces of the talus and
other features such as small ripples. |
It
can be reached from the village of Bedstone either by walking from there
or by following the lane signed to ' Darky Dale' for about 1.4 km than
taking the lane to the R down into the valley. Park opposite the top of
this lane and walk down then follow the unsigned footpath across the
stream (no bridge) and over some fields. The footpath the site is on is
connected to the forestry commission trail of Hopton Titterhill.
Parking is therefore available at the car park for this trail but this
is some distance away. (It is suggested that a copy of the mountain
bike trail is obtained for further reference). |
LGS Yes. This is a good open site suitable for parties of all sizes.
It is on a footpath so access is easy once the path is located! The
slump features are easily recognized as is the bioturbation. |
Sedimentology/Stratigraphy |
| 0051 |
SO 357 970 |
Stiperstones (Nipstone
Rock) |
Crag |
Ordovician: Arenig Series: Shelve Group: Stiperstones Quartzite. |
Frost shattered tor and boulder scree on prominent NNE/SSW trending
ridge. |
This tor is separated from the main Stiperstones ridge to the north by a
fault running up the intervening depression (BGS Shelve Inlier map
1:25000). It is now even prominent than before as the Forestry
Commission (with English Nature and the SWT) have felled the conifers
that were at the bottom of the slope to the W and some of those behind
the tor to the E. They have also cleared the small scrub trees that
were growing all over these slopes as part of the 'Back to Purple'
campaign. The steeply dipping beds of the quartzite can be made out
although it is confused slightly by the strong joints that run at 90° to
the bedding and a second set that run 90° to the first set. This
jointing pattern is the same as described for the other tors on the
ridge (ref.1). Along the ridge (S) from this tor there is further piles
of bolder scree (and in-situ rock) in which pieces of the beach
conglomerate can be found. There are pieces with a range of textures
from poorly sorted coarse conglomerate (with sub-rounded quartz pebbles
of a up to 10 mm in diameter) to the main blocks of the tors which are
fine grained. The conglomerate also contain pebbles which are of other
material such as purple Longmyndian sandstone. Quartz veins can be
found in many of the pieces some of which show well formed (if small)
crystals. From the top of the ridge there are views all round such as W
to Mitchells Fold and Corndon; S down the valley towards Lydham and N up
the rest of the Stiperstones ridge. Also there is a fenced off area
which is marked on the BGS map as a shaft. This is cut down into the
quartzite to a depth of about 15 m. It is conceivable that the W end of
this excavation stops against the Mytton Flags which form the slope
below the quartzite ridge. It is not possible to tell this for certain
as the shaft is fenced and has very steep and therefore dangerous
sides. Outside the fencing there is a small patch of gravel type
material that looks much like the mine waste at the Bog Mine. This
could have been a tip from this shaft and contains minerals such as
quartz; calcite and barite. |
There is a car park just below the outcrop on the E side of the Bog to
Linely road. There is a footpath that passes round the base of the tor
and continues along the ridge. This path is not on the Explorer map
(216) but is signed on the ground just up the track from the carpark.
The shaft is off the path but at present it is easy to get down the
slope. |
LGS Yes. This is a good site with mining interest as well as the frost
shattered tor. It has easy access and carparking and (on a good day!)
has good views to the other tors. |
Structure and Sedimentology/Stratigraphy |
| 0052 |
SO 357 978 |
Bog Mine - Stiperstones |
Mine/adit |
Ordovician |
Mine workings below the Stiperstones ridge. |
This site has been partly reclaimed and re-vegetated (with limited
success) with some of the mine waste being removed by farmers for
hardcore. Some of the mine buildings are still standing along with many
more foundations. The waste tips are still evident and the white
minerals (barite calcite and quartz) are still very much in evidence
especially where erosion has revealed new material. There are
information panels here explaining the mining and therefore much of the
geology. |
Large car park with information board and mine buildings; about 2.5 km
south of Stiperstones village (where there is a pub!). In summer there
is a shop and excellent tea room operating at the old school; this also
serves as a field centre. |
LGS Yes. This is an important mine site and one of the most which are
accessible to the general public. There are some minerals to be found
and it already has interpretation in place. |
Mineralogy/Petrology |
| 0062 |
SJ 390 046 |
Poles Coppice - Pontesbury |
Quarry (disused) |
Ordovician: Arenig Series: Shelve Group: Stiperstones Quartzite (BGS
Shelve Area). |
This site is on high ground towards the N end of the SW/NE trending
ridge made by the resistant Stiperstones Quartzite that continues from
the Stiperstones. To the N is the low undulating ground of the edge of
the North Shropshire plain. |
The main quarry (and the only one with an obvious path into it) is very
large; about 200 m across and 20 m high. However there is a lot of
scrub on the quarry floor and some up the faces at either end. There is
a clear patch in the middle of the quarry but the view of it is still
becoming obscured by the trees. The faces are very steep and there is a
lot of loose scree at the foot of them that makes it difficult to reach
the in-situ rock. The bedding is almost vertical (dip W) and is
slightly undulose in places. It is difficult to determine the grade of
the quartzite in the different beds without hammering sst the faces.
The loose material indicates that the quartzite ranges from very fine to
coarse. There are very few thin siltstone bands between the quartzite
beds. There is one obvious fault towards the top of the face. Above
the fault the rock has iron rich staining whilst the beds just below can
be seen to bend up as an affect of fault drag. There are tips of
quartzite 'rubble' all over the floor of the quarry amongst the trees.
There are two other smaller quarries in the vicinity (as marked on the
OS Pathfinder map). Neither of theses are accessible but the 'black
route' through the nature reserve pass between them and allow a view
down in to them. |
These quarries are within the County Councils nature reserve area and
can be reached by following their colour coded paths. The nearest car
park is the one at the N end of the reserve which is reached from
Pontesbury. |
LGS Yes. This is a good site which demonstrates the nature of the Stiperstones Quartzite with some faulting. It is a large site with easy
and access close to centres of population and suitable for large groups. |
Structure and Sedimentology/Stratigraphy |
| 0063 |
SO 390 858 |
Edgton Farm (Dunslow) |
Bank |
Silurian: Ludlow Shales. |
The exposure is at the base of a steep scarp slope of a small ridge
running NE/SW. From the top of the scarp there are good views of the
surrounding hills including the Stiperstones ridge Corndon the Longmynd
Caradoc the Clee Hills and Bury Ditches. |
The exposures are mostly on the banks of a track to the left of where
the Shropshire Way climbs the scarp slope of the ridge. The outcrops
themselves are obscured slightly by lichen and moss but they generally
are not overgrown so the structure is clearly visible. They show thinly
bedded siltstone which is calciferous in places but doesn't appear to
contain any calcareous nodules. The beds dip gently to the SE and are
usually 10 mm thick or less. Graptolites are plentiful and are found in
various states of preservation. They can be found in the abundant loose
material which lines the track. Other fossils such as orthocones can
also be found but these seem to be less common. There are also small
exposures in the lane that the footpath follows from the road. However
these are quite vegetated and only really suitable for research
purposes. |
From Edgton follow the Shropshire Way south through a few gates. The
public path climbs the steep scarp slope up the fence line but the
exposures are on the track that bends to the left. Park on the road in
Edgton. Or there is lots of space at the village hall on the west side
of the village if the gates are open. |
LGS Yes. Designation as an easily accessible safe place to study rocks
of a graptolitic facies. It provides a good comparison to the areas of
Edgton Limestone in the area and also with the other graptolitic
siltstones at the west side of the village. There are also good views
from just a bit further up the path making it an interesting
geomorphological site. |
Fossils |
| 0064 |
SO 382 831 |
Burrow Hill Fort - Hopesay |
Crag |
Silurian: Ludlow Series (undivided W of C/S fault; BGS Sheet 166). |
The hill fort has been built on the higher summit of a two-summit
ridge. There are good 360° views of the surrounding countryside. |
There are several small outcrops (max of a few metres in each direction)
incorporated into the banks of this impressive hill fort. The ones found
on this visit were at the SW end of the fort in the vicinity of the
highest point. They showed flaggy uneven beds of siltstone (<10 mm to
50 mm thick) dipping at about 20° to the S. There was not much loose
material by the outcrops but near the S entrance to the fort there is an
abundance of loose scree. This proved to be unfossiliferous but a few
pieces showed some bioturbation. The view from the top is very good.
Because the fort area has not been forested there is a clear view of
360° (only obscured by a few old oak trees). This shows all the local
hills and as far as the Clee Hills Caradoc etc. Along the tracks that
run below the fort to the west there are further outcrops partly exposed
due to the recent clearance work in this area. These mostly show thinly
bedding siltstones dipping gently to the S. However at GR 379831 (just
by a track junction) there is an abrupt change of dip (from about 10°S
to 45° and more to the E); disturbance and jointing of the beds. This
would appear to be a fault zone as the structure is lost for a few cm.
Despite the enormous amount of loose material that covers the tracks in
places there is very little evidence of fossils. The rock is quite
micaceous in places. |
There is no public path to the hill fort but there are tracks through
the surrounding woodland that lead to the fenced off fort. The easiest
of these to follow are up the W side of the hill. These fork off of a
path that follows the Shropshire Way from Hopesay. Park in Hopesay. |
LGS Yes. LGS designation particularly for its view of the surrounding
countryside. There is also some interesting (if small outcrops) with
possible faulting. |
Geomorphology/Landscape |
| 0067 |
SO 417 792 to 418 790 |
Brandhill Quarry - Onibury |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group (BGS Sheet 166). |
A
very impressive set of faces from which there is a good view W down the
valley towards Clungunford. |
As
described in the previous report this is a very striking site. It is
still very open with very little coverage of the faces by vegetation.
Despite the almost horizontal bedding it is possible to reach about 2/3
of the exposed beds due to the undulations of the ground directly in
front of the faces. There is some loose material in which fossils can
be found. |
This is next to a bridleway and not fenced off from it. However
permission should be sort from the owners at Brandhill Farm. There is
no parking except along the verges. |
LGS Yes. The assessment states that ‘Brandhill Quarry warrants LGS
designation if only for the aesthetic quality of its situation and
architecture; it is however a significant locality in the context of the diachronism of the Aymestry Limestone facies.’ |
Fossils and Sedimentology/Stratigraphy |
| 0068 |
SO 448 837 |
Top of Halford
Wood |
Spoil heaps |
Silurian: Ludlow Series: Aymestry Group |
Spoil heaps are on top of a small scarp slope formed from Aymestry
Limestone. 360 degree views around Shropshire including Clee Hills;
Stretton Hills; Whitcliff; Clun Hills; down to The Malverns and west to
Radnor Forest. |
Spoil heaps made up of very fossiliferous; nodular Aymestry limestone
each about 4m high. Heaps are stable. Calcified fossils include several
types of brachiopod and crinoid. Disused quarry as marked on Pathfinder
map is no longer discernible. Great views as described above. |
Via public footpath from west of Whettleton Pool (444830) about 750 m up
scarp slope. Heaps and views are just of the path beyond the top of the
wood. |
LGS Yes. The landscape views are the best showing geomorphology of
Shropshire. Plus some fossils and rocks showing nature of Aymestry
limestone which makes up the scarp you are on. |
Geomorphology/Landscape |
| 0071 |
SO 512 741 |
Ludford Corner |
Cutting (road/railway) |
Silurian: Ludlow Series; transition to Pridoli Series. |
Roadside cutting on junction |
Exposure of thin beds (<50 mm) of siltstone. Transition from Silurian to
Pridoli; formerly considered to be Devonian. Plaque at base (behind
bench) tells of Murchison's interest in the Bone Bed. This is now
backfilled but had become a deep slot due to excavation for fossils (an
exposure has been deliberately left free from burial 50 m up the road by
the speed limit sign). Main exposure is on the junction of Richards
Castle road and Whitcliffe road. It continues up both sides for about
50 m but space is restricted and the road is very busy. This was once
the classic locality for the Ludlow Bone Bed. |
On
junction of roads. Parking for two or three cars in minor road opposite |
LGS Yes. As part of a designation that covers the whole of the Whitcliffe Common area. |
Fossils and Sedimentology/Stratigraphy |
| 0072 |
SO 288 742 |
Lurkenhope - Stowe |
Quarry (disused) |
Silurian: Ludlow Series (ref.1). |
This site is on a road which follows a steep sided; narrow; v-shaped
valley. |
The main quarry site has become very overgrown with brambles and small
trees. This along with the amount of loose scree on the steep slopes
makes it very difficult to reach the higher outcrops. The lower parts
of the quarry are more accessible and show massive bedded units up to
600 mm thick with thin shale partings. The lower parts appear to be
more massive than the higher beds which are of a more flaggy nature. At
the top of the quarry there are notable strong sub-vertical joints
trending almost N/S. The exposure continues SE along the NE side of the
road. A wide verge makes this an easily accessible and safe place to
study. The most obvious feature is the fault zone; just to the right of
the quarry; that separates beds dipping about 20°NW with from others
that are almost horizontal. The fault zone contains very broken and
distorted beds. On the rock exposed closest to the road and at ground
level there is a covering of calcite along one plane. A lot of the
loose material in this area shows degrees of calcite mineralization. To
the right of the fault zone the rocks appear to form a very flat
syncline. In these beds the sedimentary features reported in the
previous report are clearly visible in the almost cyclic bedding of
massive siltstone beds separated by a few cms of fine laminated
siltstone. A few fossils were found scattered in the siltstone with the
occasional bedding plane having a covering of brachiopods. |
This site is on the A488 Knighton to Clun road. It is found on the NE
side just on the bend N of the farm at Lurkenhope. Parking is possible
on the wide verge infront of the outcrop although this can be very soft
in wet weather. |
LGS Yes. Designated for its accessibility and usefulness for large
groups to study features associated with sedimentation (cyclic features
resembling turbidites) thin layers of allogenic fossils and structural
features of faults and folds.. |
Fossils and Sedimentology/Stratigraphy |
| 0074 |
SO 271 768 |
Selley Hall - Llanfair
Waterdine |
Quarry (disused) |
Silurian: Ludlow Series (BGS Wales 1:250000 |
Quarry cut into top of small ridge. |
This exposure is in two parts. To the E two faces of massive sltst with
some more shaley partings; join at an angle of ~80°. The beds to the S
of this junction seem to dip more steeply than those to the N (about 30°
and 20° respectively). This could be due to the affects of faulting.
These faces are about 6 m high. The planar bedding is cut by a series
of joints some of which may be small faults. There is a large amount of
loose material of all sizes. The loose material contains some small
brachiopods; bivalves and one orthocone septum was found. To the west
of the quarry the rock appears more shaley is a continuation of the beds
to the S of the junction. Again there is abundant talus beneath this
outcrop but no fossils were seen and the rock was paler. Exposure is
part of an eroded anticline the other limb of which is on Selley Hill. |
Follow the bridleway (straight ahead) through the gate on RHS of the
road about 300m up the hill from Selley Hall. The quarry is on the R as
the path bends round beneath it. As the site is not actually on the
path permission may be needed for access by groups. There is room to
park in the gate-way but it is muddy. |
LGS Yes. Easy access from road; good sized exposure with abundant loose
material. Designated as an exemplary example of a breached anticline
(erosion having removed the cracked and weakend rock on the crest of the
anticlinal fold). |
Structure |
| 0075 |
SO 322 732 |
Tournett - Stowe near
Knighton |
Quarry (disused) |
Silurian: Upper Ludlow Series |
Quarry cut into roadside bank/cliff on edge of River Teme floodplain. |
Large quarry up to 10 m high. Thinly bedded (shaley) siltstones dip into
hillside. Further exposures occur along the road towards Weston for
about 200 m. Some parts badly weathered and distorted by tree roots.
Lots of loose shaley material but few fossils found. (M.Allbutt:- 'Orthocone;
graptolites expected). Some; but very few; calcareous nodules within
the shaley bedding. |
Bucknell to Knighton road past on RHS past Weston. Bucknell 3.75 km.
Restricted parking; one car might fit in quarry but it is very muddy.
Narrow road |
LGS Yes. Good outcrops with some fossils. Very good structure in
parts. Large enough for good sized group except lack of parking. |
Fossils |
| 0083 |
SO 348 759 |
Bedstone Hill -
Bedstone |
Quarry (disused) |
Silurian: Cefn Einion Formation. |
Quarry has been cut into the side of the hill above a very steep narrow
valley. |
This is a square sided quarry with three faces up to about 6 m high and
10 m long. The left and right hand faces trend N/S whilst the back face
is at 90° i.e. trends E/W. There is a lot of rubbish which obscures
about half of the back face. The other faces are clear and accessible.
The rock is mostly flaggy siltstone / fine sandstone with some more
massive beds. There are a few beds of finer lithology that are obvious
as units about 60 mm thick. The RH face is the more interesting as it
is less flat than the other so provides a section showing the dip of the
bedding as well as faces parallel to the strike. There is some
spheroidal weathering and mm scale laminations can be seen in some of
the units on this side. Fossils were quite numerous in the abundant
loose material but their source in the in-situ rocks was not apparent as
obvious fossiliferous bands. |
This site is along one of the many forest tracks within this
plantation. In Bedstone village take the left hand turn to Mynd; then
take the first turning left signed 'Darky Dale'. This road can be
followed for about 1.4 km until a track leaves to the left at a
'cross-roads'. Park here if it is clear that there are no forestry
operations in the area. Follow the rack to the left. The quarry will
be seen on the LHS of the track after about 400 m. It is fenced off
from the track as the faces are vertical at this point. Go through the
trees beyond the quarry to reach the entrance. It is also possible to
park at the end of the metalled road where several paths meet or at the
Forestry Commission car park at Hopton Titterhill but that then requires
a long walk to reach the site. |
LGS Yes. This site has some interesting material and is a fossiliferous
and accessible example of the Cefn Einion Formation. However the
rubbish does present a hazard that should be removed. If this was
cleared the site would be suitable for reasonably large parties. |
Fossils and Sedimentology/Stratigraphy |
| 0085 |
SO 358 777 |
Hopton Park - Hopton Castle |
Quarry (disused) |
Silurian: Bailey Hill Formation. |
This quarry is cut into the bottom of the steep sided Hopton Titterhill
above the undulating valley which can be seen to the NE. |
This quarry covers a large area and is reminiscent of the spoil tips of
a Welsh slate mine. Most of the area is covered in loose material of
all sizes up to several feet across. There a few in situ exposures.
One of these (about 3 m by 10 m) is found at the top along a track that
continues directly up the hill into the woodland. Here it shows units
100-150 mm thick of dark siltstone and fine sandstone. The rocks of the
outcrop look fairly uniform in terms of lithology as do the loose
pieces. The loose material shows a good number of features that
indicate these are turbidite beds. These include tool marks and flute
casts as well as other evidence for scouring. Unfortunately on this
visit no distinctive marks could be found on the many in situ bedding
planes visible to indicate a direction of movement. Other pieces showed
mm scale laminations and light and dark banding. There was occasional
evidence of calcite mineralisation with some surfaces having a covering
of calcite. No fossils were found. |
From the B4367 Craven Arms to Bucknell road take the RH turning at
Hopton Heath and turn immediately left to Hopton Castle. Park at the
far end of the village and follow the unmarked path through three gates
and follow the track on to a forth at the bottom of the wood. The
quarry is directly S of the gate into the wood on the next track up.
Either follow the track round to the left or take the short cut straight
up the bank in front of you. This site is also on the Hopton Mountain
Bike trail route; post No.8. |
LGS Yes. It has an abundance of material showing various surface
features such as tool marks (on all scales). There is loose material to
study as well as in-situ rock. Potential for finding such nicely
'sculpted' rocks. The site is big enough for the largest of groups and
has relatively easy access. |
Sedimentology/Stratigraphy |
| 0138 |
SO 413 775 to 415 777 |
Swan Hill (Shrops) |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group. |
Quarried limestone makes a prominent feature on the side of this wooded
hill. It forms a V on the map as it crosses the small valley down which
the road runs. |
The main exposures of this quarry are to the left of the gateway with
the largest face being about 25 m and 10 m high. There are other faces
surrounding this lower quarry which is used for turning and parking of
forestry vehicles and the storage of timber. The faces show very
nodular limestone some of which are picked out by red algal growth.
The beds appear to be quite uniform all the way up but due to the
vertical nature of the faces and the very gentle dip only the bottom
beds can really be studied at this point. The nodules are a fairly
uniform size throughout this area of the exposure. There is some
siltstone this seems to be evenly spread throughout the faces as thin
bands around the nodules rather than discreet layers at intervals
separating the layers of limestone. There is little loose material
beneath the faces in this lower quarry but there are pieces in the
tracks which show the nodules to be made up either as single lumps of
colonial corals or combined fragments of other fossils. If the upper
forestry track is followed there are more exposures as are marked on the
pathfinder map. These show a slight change in the lithology through
higher beds. It is still nodular limestone but is less regular and the
'beds' of limestone begin to look slightly thinner as the nodules are
more elongate. In one small quarry where the track levels out there is
a distinct band in which large Kirkidium knigtii and other fossils
including large colonial corals can be seen in the rock face. On the
other side (N) of the road there are further exposure showing the same
things as the lower quarry on the S side. Here the land surface allows
a greater number of beds to be studied (if to limited extent). There is
quite a bit of loose material here although a lot is hidden under the
ground vegetation. |
These quarries are situated on a minor road between Shelderton and
Onibury. They are marked on the Ludlow OS Pathfinder map No. 951
(SO47/57). The main quarry is on the S side of the road (on the R when
travelling up hill from Shelderton). Parking is limited to the verges
which are a reasonable width in places but can be quite soft. The
quarries on both sides of the road are fenced off and the gates are
padlocked. Care must be taken if there is any sign of forestry
operations. If the owner is identified it may be possible to negotiate
parking in the quarry? |
LGS Yes. This should be designated as a LGS as it is quite an easily
accessible site; suitable for large parties and showing the nature of
the Aymestry Group. There are plenty of beds to study and loose
material in which to find fossils. With the exposures along the track
and on the other side of the road studies can be made of vertical
changes in deposition and lateral changes to a limited extent. |
Sedimentology/Stratigraphy |
| 0144 |
SO 418 778 |
Shelderton Rock |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group. |
Quarried limestone makes a prominent feature on the side of this wooded
hill. It forms a V on the map as it crosses the small valley down which
the road runs as well as a few other small quarries in the hillside of
which this is one. |
This site is the lower of two quarries that lie on the road just above
the larger quarry of Swan Hill to which the comparisons are made. This
site shows limestone that is still nodular but the nodules are more
elongate and there is a higher proportion of siltstone that gives it a
more flaggy appearance. The loose pieces (often more silty than
limestone) are stacked with small shells (10 mm and less) rather than
being lumps of coral or large brachiopods. The faces are about 10 m
high and many beds are accessible with care. The rocks dip gently E.
On one face there is a calcite covering which is probably due to
infilling of a joint. The calcite has been given a red colouration by
algae. |
This quarry is situated on a minor road between Shelderton and Onibury
as marked on the Ludlow OS Pathfinder map No. 951 (SO47/57). The quarry
is on the S side of the road (on the R when travelling up hill from
Shelderton). Parking is limited to the verges which are a reasonable
width in places but can be quite soft. This quarry is fenced off from
the road with barbed wire and there is no gate or any other practical
way in except to climb the fence. Most of the faces can be seen from
the road. Care must be taken if there is any sign of forestry
operations. |
LGS Yes. This should be a LGS in conjunction with the site at Swan
Hill just below it and Shelderton just above to give a good section
through these horizons through which obvious changes in depositional
environment can be seen. |
Sedimentology/Stratigraphy |
| 0158 |
SO 453 794 |
Onibury - Hale
Bank Quarry |
Quarry (disused) |
Silurian: Ludlow Series: Upper Ludlow Shales. (Previous report; Lower &
Upper Whitcliffe Group). |
Quarry cut into the bottom of the valley side above the meandering River
Onny (with river terraces) which has created a wide valley through which
the road and railway run. |
The previous report covers everything I noticed on this visit as far as
the actual geology is concerned. The quarry is becoming overgrown since
it was last used for the storage of equipment during the upgrading of
the A49. Some of this equipment still remains along with a lot of
blocks of concrete pipes and other material. A lot of this has become
overgrown making it difficult underfoot. The faces themselves are still
quite clear except for the RH end which is covered in brambles etc.
There are some spreading trees on ledges on the back wall which will
obscure quite a lot in the summer. The vegetation on the floor of the
quarry has also obscured a lot of the loose material. However there is
some loose material just outside the gate in which fossils can be
found. On this visit abundant Rhynchonella were found along with
colonial coral and one trilobite pygidium and a cephalopod septum. Also
in this material there was evidence of calcite mineralisation. |
This site is accessible off the A49 just N of the level crossing at
Onibury. There is not really room to park in the gateway so park in
Onibury village. The gate is padlocked but a small path in the
vegetation the other side suggests regular use by people on foot. |
LGS Yes. Provides a section in Lower and Upper Whitcliffe Formations
allowing direct comparison with the standard section at Ludlow. The
quarry also provides a logical culmination to the A49 road section
previously designated as a LGS. |
Fossils and Sedimentology/Stratigraphy |
| 0178 |
SO 505 746 |
Dinham Quarry -
Ludlow |
Quarry (disused) |
Silurian: Ludlow Series: Whitcliffe Formation. |
Large quarry cut into base of Whitcliffe; behind Clive Cottages |
The largest E-W trending face of the main quarry is about 150 m long and
~25 m high. Beds dip very gently to the NW looking almost horizontal in
the main face but overall the dip of the Whitcliffe Beds here is 10°
towards the north-north-west (consistent with its position on the
northern flank of the Ludlow Anticline). Fine calcareous sst and sltst.
Bedding sometimes undulates and is uneven and/or discontinuous. Fossil
bands can be seen in the faces e.g. one that is 30 mm thick about 1.3 m
off the quarry floor to the left of the centre of the main face.
Fossils such as brachiopods and bryozoans are also to be found in the
loose material at the base of the faces. Some cross-bedding on a mm
scale can also be seen within a lot of the beds. Spheroidal weathering
is apparent in places. There are further exposures that reveal the
higher beds in the sequence. These are above and to the E of the main
quarry. They show similar features including trace fossils and
bioturbation on some of the loose material. Two prominent volcanic ash
bands about one third of the way up the main face. In medieval times
this quarry was owned by Bromfield Priory and operated on their behalf. |
Park at Dinham Bridge. The quarry is on the left hand side of the road
leading up to Whitcliffe and is reached via a small path just before
(and on the opposite side of) the caravan park (behind Clive Cottages) |
LGS Yes. It is a very impressive quarry which is easy to access and
relatively safe for parties of all ages and sizes. It could be combined
with other Whitcliffe sites. |
Fossils and Sedimentology/Stratigraphy |
| 0196 |
SO 305 839 |
Colstey (Bury
Ditches W) |
Quarry (disused) |
Silurian: Cefn Einion Formation. |
Quarry and exposure at side of track that runs down to small river
running between Colstey Wood and Red Wood. |
The small quarry has a total height of about 5 m and a length of 7 m
along the E/W exposure. At the base the beds tend to be flaggy but they
become more massive towards the top. They are siltstone and fine
sandstone. Some pieces of loose material contain abundant fossils
including several brachiopods and one large Serpulites was found. There
is some undulose bedding and the beds appear to dip about 20°W. There
are further exposure in the bank on the RHS of the track below the
quarry towards the stream. These beds can be seen behind the brambles
for about 10 m. As the track bends and crosses the stream there is an
exposure on either side of the stream. The one to the right (NW) of the
stream is the better exposure as it is less vegetated. This is about 5m
x 10m and shows massive units up to 150 mm thick and more flaggy units
only 10 mm thick. The bedding surfaces appear uneven and in-filled
burrows are visible on the surfaces of some of the loose material; with
the in-fill being paler than the surrounding rock. Very few body
fossils were found here except one bit of an orthocone. The rocks of
the other side appear to be much the same but are covered in moss;
lichen and scrub. There is another small exposure on the track running
down next to the stream but this is small and access is more difficult
due to brambles and loose material underfoot. |
This is along one of the many forest tracks in this area. The nearest
parking is at the Colstey Wood entrance. The site is down the main
track past the barrier. Alternative parking is at the Forestry
Commission Carpark for Bury Ditches. This is further from this site but
is a larger carpark and allows easier access to other sites in the Bury
Ditches area. |
LGS Yes. This should be a LGS in conjunction with other sites in the
Bury Ditches are to show different facies within the Ludlow Series. |
Fossils and Sedimentology/Stratigraphy |
| 0198 |
SO 313 819 |
Croveats Lane -
Clun (NE) |
Bank |
Silurian: Downton (Ludlow Bone Bed) according to ref.1. |
The path climbs the steep sided Radnor Wood and gives good views back
over Clun and the hills that surround it. |
This exposure reveals the Bone Bed towards the top end. This is
revealed as black layers (totalling about 80 mm in thickness) that are
obviously different from the surrounding layers. The loose pieces show
some of this very dark material to be of very broken fragments covering
pieces of more silty rock. They also show other features that may be
fish fossils. The total exposure is about 0.5 m high and 7 m long. The
other layers appear to be unevenly bedded flaggy siltstone which dip at
about 5°SW. The surrounding loose material also contains a few small
pieces of red medium grained sandstone. Gastropod fossils were found in
some loose siltstone blocks. Ref.1 states this as being a site for
Thelodus parvidens fauna Cyathaspis Sclerodus and acanthodian. |
Park in the Community Area car park in Clun and continue up the road on
foot past the Youth Hostel until the footpath branches off over the
field to the right. Follow this path and then the track up the sunken
lane. Pass through two gates. The site is on the LHS just beyond the
second gate where the path goes through a very low 'cutting'. |
LGS Yes. This is perhaps the most easily accessible exposure of Bone
Bed outside Ludlow so gives a better understanding of this important
marker horizon. There are fossils to be found in the path and the dark
fragmented material is quite clear in the exposure. |
Fossils and Sedimentology/Stratigraphy |
| 0199 |
SO 314 851 |
Acton Bank -
Lydbury North |
Quarry (disused) |
Silurian: Cefn Einion Formation. |
This quarry is cut into a small isolated ridge trending NE/SW on
otherwise flat land at the junction of several valleys. |
As
described in the previous reports there are three quarries at this
site. The first is mostly behind a barn and therefore is not very
accessible but clearly shows flaggy bedding. Along the footpath is the
next and most accessible of the outcrops. This shows more massive beds
which dip gently south and which are up to 200 mm thick. Some of these
show internal laminations. There are some flaggy beds of just 10 mm
thick. Over the surface of the face and in some of the joints there is
a weathered clay-like material containing clasts of many sizes. There
is a large amount of debris in front of this outcrop - the larger pieces
of which show the uneven nature of the bedding surfaces. To the left of
this quarry the outcrop continues for several 10's of meters but it
becomes less accessible. Here the bedding is again more flaggy in
nature with beds of just a few cm's in thickness. The site appears to be
quite stable but there are some overhangs which obviously should be
avoided. |
This site is to the east of the public footpath that runs along the side
of Acton Bank from Acton. It is at the beginning of the path where it
crosses the first stile. Park in Acton or on approach but avoid blocking
gateways. M. Allbutt suggests asking at the farm but it is not clear
which building in Acton this is. Permission should be sort for study of
the quarry behind the barn as this is not on the footpath. |
LGS Yes. Suitability for teaching purposes (including large groups) for
study and interpretation of faulting and sedimentary features; in
particular the development of slump structures relevant to its position
on the Silurian shelf/basin margins. |
Structure and Sedimentology/Stratigraphy |
| 0200 |
SO 315 874 |
Colebatch (W) - Bishop's
Castle |
Quarry (disused) |
Silurian: Bailey Hill Formation (ref.1). |
This is cut into a sharp slope just above a small meandering stream. |
This quarry shows interbedding of massive and shaley units with a steep
dip to the SE. The lithologies include dark quite micaceous fine
sandstone siltstone and a few pieces of rich brown mudstone. The
massive units are about 150 mm thick and are separated by thicker units
of the more shaley material. This interbedding follows quite a regular
pattern. The beds tend to be quite uneven with some large nodules and
spheroidal weathering in places. There is some deformation of the LH
end of the mainly NW/SE trending face. The total exposure is about 8 m
high by 30 m and most of the beds are accessible at some point. There is
an abundance of loose material that lies in the bottom of the quarry and
where there has been some recent excavation. This shows some
bioturbation but no fossils. Much of if shows very rusty weathering and
many display an oily looking sheen. |
Turn W off the Bishop's Castle to Clun road in Colebatch. After about
300 m a footpath follows a track to the right and over the stream. The
quarry is visible beyond the gate in the field. Park on the verge just
before the track or in Colebatch. Other facilities can be found in
Bishop's Castle. |
LGS Yes. LGS designation due to its suitability for teaching purposes
giving access to large groups for study and interpretation of (probable) turbidite sequences and related sedimentary features. In the context of
a position on Silurian shelf/basin margins comparison with near-by Acton
Bank is particularly relevant. |
Sedimentology/Stratigraphy |
| 0202 |
SO 322 834 |
Stepple Knoll
(N) |
Quarry (disused) |
Silurian: Cefn Einion Formation. |
This forest track runs up a small valley on the side of the prominent;
conical shaped hill. The toposcope on the summit gives a guide to the
good 360° views of the surrounding countryside. |
This excavation is now covered in young fir trees which are growing
amongst the loose material on the bedding surfaces. Some of the rock is
still unobstructed and the structure of the beds is visible even through
the trees. The rock is very broken and blocky. It dips about 20°NW.
The bedding planes are quite undulose in places. Some fossils were
found including brachiopods and ostracods but I did not find any of the
shell coquina reported by M. Allbutt. The quarry is about 50 m long
(including vegetated areas to either side of the main face) and a
maximum of about 5 m high. There are no dangerous overhangs. |
Park at the Forestry Commission car park and take the lower track marked
with a red banded post. Follow this track until a tight bend in a small
valley. At this point take the grassy path down the stream to the track
below which you should follow to the right. The quarry is just up the
slope to the right where this track meets another. |
LGS Yes. Part of the larger LGS site that takes in other sites in the
Bury Ditches area as they show how the rocks change throughout this part
of the Ludlow Series. |
Fossils and Sedimentology/Stratigraphy |
| 0203 |
SO 325 831 |
Stepple Farm
(N) |
Quarry (disused) |
Silurian: Knucklas Castle Formation. |
This is a quarry on the side of a valley at the base of the conical
shaped Stepple Knoll and Sunny Hill. |
This curved excavation is about 4 m high by about 40 m. It shows the
characteristic flat; shaley; laminated; bedding of the Knucklas Castle
Beds. The beds appear to dip gently WNW. There is most loose material
on the RHS (E) a lot of which shows an oily sheen on many of the
surfaces. On the LHS there is less loose material and the structure is
more readily apparent. Some of the debris shows there are some quite
mica-rich band within this horizon. This is a very open and safe site
with easy access to all the beds. |
This site is just off the public footpath that runs from Bury Ditches to
Stepple Farm. It is best to park in the Forestry Commission carpark and
walk along the waymarked tracks. The footpath runs around the top of
this excavation. |
LGS Yes. To be considered as a LGS site in conjunction with others in
the Bury Ditches area to show the different facies that were in the area
during the Ludlow Series. |
Sedimentology/Stratigraphy |
| 0204 |
SO 325 834 |
Bury Ditches (SSW) - Dawes
lines - Lydbury North |
Quarry (disused) |
Silurian: Cefn Einion Formation? |
Track runs along contours around the bottom of the prominent; conical
shaped hill. Toposcope on the summit gives a guide to the good 360°
views of surrounding countryside. |
An
outcrop that runs along the track between two small quarries (SO329836
to the E and SO325834 to the W). The beds are a few cm thick (compared
with mm's thick to the east). Some beds are more calciferous and these
have more rounded weathered edges than the more shaley beds. These more
massive beds are interbedded with fine shaley beds. Some fossils were
found but the fauna is still quite sparse. Allbutt describes this as
being a transition between the shaley KC beds and the more undulate and
flaggy CEF. In the western quarry the beds are obviously thicker than
they are at other sites to the east. A calcareous nodule was on the
floor and there are others in the quarry face. The beds appear to dip
NW. Fossils are evident on the bedding surfaces of the yellower; more
sandy pieces. These consist mostly of small brachiopods. The exposure
that has continued along the length of the track from the car park to
the east finally peters out just before the track reaches the small
valley and bends around tightly. |
Park at the Forestry Commission car park and follow the lower track with
the red banded post. The quarries are about 1 km along this track. Stay
on the upper of the two track where there is a choice. |
LGS Yes. As part of LGS to include all the sites in the Bury Ditches
area which show the different facies of this part of the Ludlow Series.
Designated ‘as showing a continuous section through the transition
between two principle rock formations of the area. It specifically
demonstrates the effects of shallowing of a depositional basin whereby
pelagic and oxic sediments become overlain by incoming traction
sediments with concominant changes in lithology and fauna. |
Fossils and Sedimentology/Stratigraphy |
| 0206 |
SO 329 836 |
Bury Ditches
Clun (SE) |
Track/roadside |
Silurian: Knucklas Castle Formation. |
Track runs along contours around the bottom of the prominent conical
shaped hill. Toposcope on the summit gives a guide to the good 360°
views of surrounding countryside. |
This is a small excavation (3 m high x 10 m) in the bank of the
track-side. Here the bedding is mostly thin but there are some more
massive units. There is some strong jointing and some more calciferous
areas. Rock is exposed in the track-side for most of its length. The
exposures are only ever a metre high at the most and are often less.
However walking along the track you can get a good a good feel for the
structure of this thinly bedded siltstone. The beds tend to be on a mm
scale and are rarely more than 10 mm thick. The angle of dip appears to
vary slightly as does its direction. M. Allbutt suggests there is a
flat anticline visible in this section. There is lots of loose material
along the track but this is very broken and consists mostly of pieces
just a few cm in the largest direction. The beds get slightly more
massive towards the SW end of this section at a small quarry (see
SO329836). No fossils were found in any of the loose material along this
section. |
Park at the Bury Ditches carpark and take the lower track marked with a
red banded post. The exposure is on the N side of this track just at
the fork of two tracks. |
LGS Yes. To show the progression through the various horizons of the
Ludlow Series. |
Fossils and Sedimentology/Stratigraphy |
| 0207 |
SO 329 838 |
Bury Ditches
Clun (E) |
Quarry (disused) |
Silurian: Cefn Einion Formation. |
Quarry in ditch of hill fort which is on top of Sunny Hill. From the top
there are great views interpreted with the aid of a toposcope. |
This is a small pit in the inner ditch of the hill fort. A lot of the
pit is covered in grass but there is still a clear exposure on the back
wall. It shows siltstone dipping gently to the west. M. Allbutt
mentions areas of diverse fauna but only a few small brachiopods were
found on this survey. A lot of the loose material that may have been
around here is covered in grass but there is still sufficient material
to be found. On the track back towards the main car park a tree has
fallen over revealing a large amount of loose material beneath its
roots. This is a pile of recently exposed (and therefore quite 'clean')
flaggy siltstone containing a few fossils. |
Park at the Forestry Commission carpark for Bury Ditches and follow the
main track up to the hill fort. The site is over the stile and to the
right of the E entrance to the fort. |
LGS Yes. To be included in the LGS of this area; very close to the car
park and to the summit which is good from a geomorphological point of
view. |
Geomorphology/Landscape |
| 0215 |
SO 349 872 |
Stank Lane quarry - Lydbury
North |
Quarry (disused) |
Silurian: Bailey Hill Formation. |
Quarry is cut into the slope near the top of the valley side overlooking
Lydbury North and over to Bury Ditches. |
This quarry is now becoming very overgrown with nettles and wild roses.
The faces are still quite clear; despite a few patches of grass growing
on ledges; but not very accessible. The deformation and slump folding
of the rocks has produced elongated blocks of rock. The folds
themselves are still very visible in the exposure. There is abundant
loose material some of which contains lots of fossils whilst others just
contain a few brachiopods or bryozoans. |
This site is to the N of Stank Lane directly north of Lydbury North. It
is behind a barn used at present for straw storage. The quarry itself
is fenced off from the surrounding field. There is no public right of
way through the field. |
LGS Yes. On account of its exhibition of the Bailey Hill Formation of
ref.1 near the eastern extremity of its range; for the clear
demonstration of small scale slump structures pertinent to its position
on Silurian shelf/basin margins and for the wealth of its fossils’ M. Allbutt's assessment. |
Sedimentology/Stratigraphy |
| 0217 |
SO 352 811 |
Purslow (W) - Clunbury |
Quarry |
Silurian: Bailey Hill Formation. |
Small quarry on lower slopes of wide valley of the River Clun. |
The quarry is about 5 m high by about 20 m which trends NNW and shows
mostly massive beds of fine dark grey sandstone and siltstone. There is
a lot of loose material many pieces of which show closely packed and
aligned tool marks or uneven bedding surfaces. Other pieces show an
oily sheen. There is one area which may show a possible fault. This is
a 1.5 m wide vertical region of very broken rock and clay-like material
where the structure seen in the rest of the face is no longer visible.
Some areas have been stained by iron rich deposits giving them a rusty
appearance. The faces seem fairly safe with just a few areas where
there is a thick soil overhang. Since the previous report of 1997 this
quarry has been much extended. Dips range from zero to 45° towards the
SE quadrant. The BGS sheet shows a dip arrow of 11° to SSE. What was
previously taken as evidence of slumping is now abundantly confirmed as
due to large scale slumping combined with two instances of smaller 1 m
scale slump folds verging to the SE. In detail one of these shows that
slumping is the cause of a millimetre scale corrugation of bedding
surfaces examples of which are prolific amongst the talus. This quarry
provides another exposure of slumped Bailey Hill beds in the eastern
part of Ref 1; see cross-referenced reports |
This Quarry is on the N side of the B4368; Clun to Craven Arms road
about 750 m west of Purslow. It is open to the road and at present
allows plenty of space for parking. |
LGS Yes. LGS designation because this offers the most accessible local
exposure of slumped Bailey Hill beds which offers the opportunity to
study slumping (typical of this horizon) and possibly faulting. However
as a ‘working quarry’ one would wish to avoid any possibility for
conflict with owner/occupier. |
Structure and Sedimentology/Stratigraphy |
| 0218 |
SO 353 834 |
Kempton (NW) - Clunbury |
Quarry (disused) |
Silurian: Bailey Hill Formation. |
Quarry in the ridge that forms the NE slope of a small valley. |
This is quite an impressive almost circular quarry now used as a dump
for tyres and fencing. Despite the rubbish a lot of the floor is quite
clear and many of the faces are easily accessible. The highest faces
are about 10 m high but some are covered in trees and scree. Slump
bedding is visible especially on the face to the NW of the entrance.
Here the beds are contorted into tight folds. The area of folding is
quite obvious as it has weathered differently to other areas. Other
faces show areas of flat; continuous bedding but which has bowed down
slightly in the middle over a distance of a few meters. The bowed beds
are a few cm thick with more massive units above and below. There is a
lot of loose material on the RHS of the entrance some of which shows
slight bioturbation. Some of the faces and talus slopes are quite
unstable but there is plenty of safe areas to study. |
Park at Kempton (there is a lay-by by a telephone box on the B4385) and
take the footpath that goes up the valley towards Lodge Farm. The
quarry is on the RHS of the track just before a cattle grid. |
LGS Yes. LGS because of its several examples of well-formed slump
bedding of a quality which would allow quantitative measurements to
establish the direction and inclination of the palaeoslope on which they
occurred This is also a very easily accessible site showing features
that would be of interest to people of most knowledge levels. |
Sedimentology/Stratigraphy |
| 0222 |
SO 378 815 |
Oaker Wood (S) - Hopesay. |
Quarry (disused) |
Silurian: Ludlow Series (upper; ref.1). |
Quarry at the end of an elongated hill with two summits; the
northernmost and highest of which is topped by Burrow Hill Fort giving
360° view of the surrounding countryside. |
A
large quarry with clear open faces showing units of siltstones up to 2 m
thick dipping about 20°SE. The beds get thinner towards the top of the
faces that are about 30 m high and 60 m wide. There is quite a lot of
loose material which shows some bioturbation and some fossils. The
fossils (brachiopods) are patchy with some loose pieces showing a lot on
the bedding surfaces whilst others only show a few. The beds themselves
appear to be featureless. To the LHS of the quarry entrance there is an
area under an overhang that shows beds apparently dipping to the N; it
looks like a shallow syncline. However there also appears to be a fault
zone in this region which may have caused some disturbance of the dip.
The floor of the quarry is covered in low vegetation and some rubbish.
The faces are also covered in places by brambles ivy and small trees but
there is access to the base of the faces. There is no access to higher
up the faces as they are vertical. |
This site is just to the N of the B4368 about 1.3 km W of Aston on Clun.
It is along a footpath which is also a track so vehicles can reach the
quarry although permission should be sought for this. There is a piece
of wire that has been put across the entrance but this is the only
barrier. |
LGS Yes. This is the type-locality of Salopina lunata. Capable of
accommodating large groups and shows bedding typical of this horizon. |
Fossils and Sedimentology/Stratigraphy |
| 0258 |
SO 397 865 |
Ridgeway Hill |
Quarry |
Silurian: Ludlow Series: Edgton Limestone (BGS Sheet 166). |
Quarry is cut into the end of a 'hogback' ridge which runs NE/SW. There
are good views from this ridge especially up the Stretton Valley to
Caradoc and the Lawley. |
At
the LHS of the quarry there is a metre or so of deformed nodular
discontinuous beds belonging to the Edgton Limestone that pass up into
flatter more continuous calciferous siltstone beds. Also in this area
there appears to be a fault with fault beccia. The dip is generally in
a SW direction. Due to the way the quarry has been cut this results in
on face being a bedding plane. This clearly shows the sub-vertical N/S
trending joints which are mostly in-filled with calcite. There is
abundant evidence of calcite mineralisation and there are good pieces to
be found amongst the loose material. At the back of the quarry there is
a banded region showing paler more calciferous beds inter-bedded with
darker ones. The paler beds have weathered to a yellow colour and often
contain a lot of small solution hollows. No identifiable fossils were
found on this visit. |
This is on the junction of three paths the shortest of which leaves the
Edgton to Horderley road opposite Ridgeway Farm. One path continues
along the ridge from which the good views can be seen. Park on the verge
or in Edgton. |
LGS Yes. This is an impressive quarry which may have been reworked
recently as there is a large pile of loose material in the centre; this
should be avoided as it looks quite unstable. There is plenty of loose
material elsewhere. Designated as a LGS as an easily accessible site of
this 'limestone' as a comparison with other lithologies in the region
and for studies of calcite mineralization and faulting. It is a
definitive location of rock of Wenlock age west of the Church Stretton
fault and is a superb viewpoint for a landscape developed from the
underlying geology. |
Fossils and Sedimentology/Stratigraphy |
| 0275 |
SO 406 855 |
Smeathen Wood |
Track/roadside |
Ordovician: Caradoc: Harnage Shales. |
Small excavation in hollow next to ridge formed by harder Hoar Edge
Grit. |
This is a track-side excavation mainly for the purposes of research
(mostly W.T. Dean of Cardiff University). It consists of three 'bays'.
The eastern most one is the largest and shows the best structure of this
rock which is predominantly siltstone. Some bedding planes are
extremely fossiliferous with brachiopods; trilobites; crinoids;
ostracods and bivalves all present. The specimens are diminutive and
fragmented. There is evidence of folding with at least one anticline
seen by Allbutt There is a small old highly vegetated excavation where
the track begins to rise up the ridge to the west. It is possible that
the rock here is HEG and a possible transition between the two can be
seen (ref.3). |
Continue NW from Cheney Longville for about 1.5 km. The excavation is
down the RH track that leaves the LHS of the road. Parking is limited
to the verge which is very muddy. |
LGS Yes. LGS since the rich fauna which is obtained therefrom has
great value in the research of ostracodes and early chordata |
Fossils |
| 0278 |
SO 408 871 |
Horderley - Edgton |
Natural exposure |
Silurian: Wenlock Series: Edgton Limestone (Equivalent to Wenlock
Limestone and Tickwood Beds) or calcareous Wenlock Shales? (BGS SO48;
Craven Arms 1:25000). |
Exposure above track on S side of River Onny where spring emerges from
hillside. |
This is an exposure above the track that crosses the Onny River at
Horderley. It extends for about 20 m along the track and is about 3 m
high. There are two lithologies present. There are siltstone bands and
much paler bands which are calciferous siltstone; verging on limestone.
The softer fawn coloured bands are bounded by very thin (2 mm) harder
layers. Some of the rock looks very pale and chalky whilst others are
covered in rust staining indicating iron rich rock. There is some loose
material which is generally less broken and fissile than that across the
road at GR SO408874 indicating a change of lithology between the two
sites. This could be the transition between Wenlock Shales and Edgton
Limestone. There was some very bioclastic limestone pieces but these
could be from the hardcore used on the track although they are found
quite high up the bank. Few other fossils were found in the rest of the
rock. |
This site is on the RHS of a footpath that leaves the A489 at Horderley
and crosses to the S side of the River Onny. It is about 50 m along
this path from the road. |
LGS Yes. This is an easily accessible safe site that demonstrates a
change in lithology and is close to other sites so providing a 'story'
for an itinerary. Suitable for small groups. Transition between
Silurian Wenlock Shales and ‘Edgton Limestone’ as mapped by BGS circa
1964. The latter is now better regarded as the Edgton Limestone member
of the Aston Mudstone Foramtion of the later BGS Sheet 165 of 1994.
Boundary also includes a site of active tufa formation along old river
cliff. |
Fossils |
| 0283 |
SO 410 852 |
Longville
Plantation (S) |
Quarry (disused) |
Ordovician: Caradoc: Chatwall Sandstone and Chatwall Flags (transition). |
Cut into bottom of steep sided hill. |
About 85% of this quarry is now covered in vegetation; mostly brambles
and small diameter trees some of which have fallen over. The best
exposures are on the back wall which shows steeply dipping beds. There
appear to be localised changes in dip with the beds near the top looking
almost horizontal. Some of the cleaner faces show characteristic purple
banding in massive sandstone. Some other layers show much thinner beds
of finer material. There is a lot of loose material on the floor of the
quarry which show a number of features including: bioturbation; worm
burrows; flute casts; slickensides and ripple marks. The site has been
noted for the transition between Chatwall Sandstone and Flags and
haematite staining in certain areas (Allbutt). A lot of the lower slopes
look quite unstable and the upper beds cannot be reached safely at
present. |
Follow the permissive path through the bottom of the wood from the
entrance on the road about 750 m NW of Cheney Longville. The quarry is
situated on the left hand side just before the path reaches the stream
at the bottom of the hill. Park at the entrance. Other facilities in
Craven Arms. |
LGS Yes. LGS for the following reasons: ‘the stone is Chatwall
Sandstone and whilst many quarries for this stone can still be found
(none working) the purple banding is rare. This quarry does however
contain strata with this banding.’ |
Mineralogy/Petrology |
| 0289 |
SO 412 851 |
High Wood (N)
(Longville Plantation south) |
Quarry (disused) |
Ordovician: Caradoc: Chatwall Sandstone. |
Quarry cut into bottom of steep sided hill. |
The beds of Chatwall Sandstone dip gently to the SE and are generally
quite massive but with fossil lenses clearly visible at intervals up the
section. Some evidence of slickensides can be seen on loose material to
the LHS; fossils can also be found in this material. The bedding planes
don't appear to show as many features as those at Longville Plantation
LGS (SO410852). The faces are partly obstructed by brash and waste
plaster that has been dumped. However the faces to the L are easily
accessible. There is much more loose material and some exposures
extending about 100 m on the other side of the stream. This site is
presently used as a storage site but the rock is still accessible
behind. The talus shows some sedimentary features and fossils but the
structures of the exposures especially to the W end is much less clear. |
Fork left in Cheney Longville past the castle and take the footpath that
goes NW over a stile and along the fields. The quarry is in the wood on
the right; off the path and through another gate. |
LGS Yes. Combined with the existing LGS in Longville Plantation
(SO410852). This is a large excavation with faces about 15 m high. It is
very accessible and big enough for large groups (especially if brash is
removed). It also seems more stable than the other quarry. A good
example of the lithology of and fossil coquinas within the Chatwall
Sandstone of the Ordovician. |
Fossils and Sedimentology/Stratigraphy |
| 0290 |
SO 412 861 on list (SO 411 861 in ref.1) |
Onny Valley |
Quarry (disused) |
Unconformity between Ordovician (Caradoc: Hoar Edge Grit) and
Precambrian (Longmyndian). |
Quarry cut into steep river bank. |
Exposure of the unconformity between the Ordovician and the
Precambrian. This is seen in a small weathered-out exposure at the top
right of the outcrop above the steps. The contact between the HEG and
the weathered sandstone of the Longmyndian can be made out. It is
overhung by soil and tree roots. The rest of this quarry is in HEG which
has some good beds showing current bedding and solution hollows in the
more calcareous layers. The beds dip steeply to the SE and their
structure is very clear. |
This site is at the W end of the Onny Valley trail and is reached
quickest from the footpath that leaves the A489 at Glenburrell. However
parking is better at the other end of the trail in a car park off the
Cheney Longville road. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Sedimentology/Stratigraphy |
| 0293 |
SO 413 859 |
Smeathen (ESE) |
Quarry (disused) |
Ordovician: Caradoc: Chatwall Sandstone. |
Quarry on top of the bank above the river. |
This quite a large (80 m x 50 m) but very shallow (2 m) quarry. There
is not much exposed in situ rock. Most of the surface is covered in
loose material which shows hummocky bedding; ripple marks and
bioturbation. At the S end there is a deeper pit which exposes steeply
dipping; almost vertical beds. They curve over towards the top which
will be an affect of faulting associated with the Church Stretton (F3)
fault that runs just to the E of this site. These beds are a
continuation of those seen by the Glenburrell railway bridge (413860).
The rocks in the quarry are sandstones and some siltstones. The quarry
is quite grassy in places and there is some rock which is alien to the
site which has been dumped here. |
From the Onny Valley path go over the Glenburrell railway bridge. The
quarry is in the field to the left up the track just before it turns to
tarmac. Permission should be sort or the gate climbed. Alternatively
it can be reached down the track leaving the road NW of Cheney Longville
at GR412855. It is possible to park where the track turns to grass. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Mineralogy/Petrology |
| 0301 |
SO 415 859 |
Horderley Quarries
(Milestone) - Wistanstow |
Quarry (disused) |
Ordovician: Caradoc: Chatwall (Horderley) Sandstone. |
Quarry at base of hillside above main river valley. |
As
per M. Allbutts report (LGS report). This site is very overgrown in
the quarry back from the road and the brambles and scrub on the bank
make it difficult to reach. There is plenty of loose material within
the quarry which is fossiliferous and shows sedimentary structures. The
roadside face is still quite clear but could become overgrown. |
This site is on the N side of the A489 about 2 km west of the junction
with the A49. There is plenty of room to park on the wide verge in
front of the newly painted mile stone. |
LGS Yes. Type locality for Horderley Sandstone; part of a large site
taking in the Onny Valley trail (see attached note). Reasons for
designation: a) ease of access to strata with a rich fossil content and
good sedimentary features with much use made by visiting local
geological groups b) as a major source of the distinctive local building
stone. |
Mineralogy/Petrology |
| 0304 |
SO 419 849 |
Cheney Longvile (W) -
Wistanstow |
Cutting (road/railway) |
Ordovician: Caradoc: Cheney Longville Flags. |
Road side exposure as road climbs steeply. |
The exposure at the above GR is badly weathered but this does help to
pick out different lithologies (different grades of sst and siltstone
dipping SE). There are some local distortion of dip at the top due to
the affect of tree roots. Changes are easy to see so would be good for
a mapping or logging exercise except it is on a nasty bend. There is
some loose material but not very much and no fossils were found in it on
this visit. There are more exposures all along the road up the hill;
travelling west. These show a variety of bedding thickness from <10 mm
to 200 mm. (Don't mistake the dry stone wall for outcrops!!). This
must pass down through the series of Cheney Longville flags and will
include some alteranta Limestone (according to the 1:25000 Craven arms
map). A small shallow quarry is cut into the LHS of the road near the
brow of the hill (414853) which is in Chatwall Sandstone. This shows
flaggy sandstones again with no fossils being found on this visit. |
These are all on the road heading west out of Cheney Longville. Park in
Cheney Longville where the road is wider; or in the gateway of Longville
Plantation at the top of the hill. All other facilities can be found in
Craven Arms. |
LGS Yes. The first GR given is already designated as a LGS mainly as
the de facto type section for upper Cheney Longville Flags. The whole
of the road from Cheney Longville west to the beginning of the Longville
Plantation is included in this designation. The road includes two stratotype localities according to the list I have been given (418849
and 418851). It gives a good section through the Cheney Longville Flags
(including alternata Limestone) and into Chatwall Sandstone. The east
of the village it is mapped as Acton Scott Group and if an exposure of
this could be found on the road it would extend the story further. |
Sedimentology/Stratigraphy |
| 0305 |
SO 418 857 (SO 418 856 in ref.1) |
River Onny
(railway) |
Cutting (road/railway) |
Ordovician: Caradoc: Alternata Limestone |
Railway cutting. |
The exposure itself is obscured by vegetation but the structure (SE dip)
and lithologies (flaggy siltstone and micaceous sandstone along with the
limestone lenses) are still discernable. This is a very small exposure
in a shallow cutting of the old railway. There has been a sign here but
this is illegible and the post is no longer in the ground. There is
still plenty of loose material that shows fossils both as casts and
still calcified. |
This can be reached either along the permissive path that follows the
old railway track from Cheney Longville car park along the footpath that
leaves the A489 at 417858 or from the other end of the permissive path
that leaves the A489 at Glenburrell. It is best to do the first of
these as this is where there is best parking. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Fossils and Sedimentology/Stratigraphy |
| 0309 |
SO 421 855 |
River Onny (A) |
Cliff |
Ordovician: Caradoc: Acton Scott Group. |
River cliff cut on outside bend of meandering river. |
Here the beds of the Acton Scott group can be seen dipping 25°SE. They
are overlain by coarse river gravels. When the river has high flow (as
it did on this visit) it is impossible to reach the 5 m high cliff
without waders. It can be seen from the 'beach' just up stream but the
structure is not very apparent from this distance. Undercutting by the
river has made the overlying gravel fall to the river level and slightly
obscure some of the structure. Also at high water levels the 'beach'
mentioned in ref.1 is mostly covered. Some of the pebbles from upstream
can be found including some less worn ones which contained fossils. |
This is reached off the footpath that runs along the river and over a
stile in the fence that just serves to reach this locality. Park at the
carpark on the road to Cheney Longville. The footpath runs from here. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Sedimentology/Stratigraphy |
| 0310 |
SO 421 857 |
Horderley Quarries (SE) -
Wistanstow |
Quarry (disused) |
Ordovician: Caradoc: Chatwall (Horderley) Sandstone Alternata Limestone
and Chatwall Flags. |
Quarry cut into base of hill side above valley floor. |
As
per report of M. Allbutt This area is becoming overgrown by brambles
but the main features can still be seen. The beds are breaking up at
the soil surface and some distortion has occurred as blocks have fallen
out of the face. The quarry off the road is vegetated with small trees
and a lot of ivy which is covering the faces. There are further small
outcrops along the road both to the west and the east of this site. |
This site is on the north side of the A489 about 1.5 km from its
junction with the A49. There is room to park on the verge and the faces
are easily accessible if a bit loose. All other facilities can be found
in Craven Arms. |
LGS Yes. Incorporated into a large site taking in the Onny Valley trail
(see attached note). Designated as marking the transition from
Ordovician Chatwall Sandstones through the Alternata Limestone to Cheney
Longville Flags with good accessibility and all detail in situ. (the
only other comparable site is at Soudley Quarry) |
Sedimentology/Stratigraphy |
| 0338 |
SO 444 811 |
Norton Camp
Wood |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group |
Quarry cut into top of scarp slope. Gentler slope below of Lower Ludlow
Shales. |
Quarry runs for several hundred metres along the top of the scarp.
Bedding structure is easily seen in the flat faces trending N-S.
Predominantly grey crystalline nodular limestone separated by siltstone
partings. Uneven bedding at base of tallest face in sst. Some vertical
jointing. Fossils to be found in abundant talus. Ref.1 mentions A.
reticularis; Spaerirhynchia; Strophenella and C. knightii in various
layers. Some calcite veining. Brachiopods calcified and created
solution hollows. |
Southernmost end easily accessible at junction of bridleway and footpath
from A49 at Lower Park. Otherwise accessible from footpath that runs
along top of scarp. Parking on lanes at start of footpaths or in
Craven Arms. All other facilities available in Craven Arms. |
LGS Yes. Structure easily visible. Different lithologies noticeable
indicating different facies. Zoning of fossils (ref.1). Good access
and big enough for larger groups. Good for excercises such as logging. |
Fossils and Sedimentology/Stratigraphy |
| 0344 |
SO 447 822 |
Norton Camp
Wood scarp |
Quarry |
Silurian: Ludlow Series: Lower Ludlow Shales or Aymestry Group. |
Excavated along track on scarp slope of ridge below earthworks. |
Quarry extending about 70 m along track; 4 m high. Well bedded lmst and
fine sst and sltst. Bedding structure more visible down track (S) than
in quarry itself. Some of the lmst very crinoidal (to N) more
brachiopod rich to S. Lots of talus containing various fossils.
Further small exposure on R of track-side continuing up the track
towards the Camp. Could find transition from Lower Ludlow Shales to
Aymestry Group along this track with further investigation? |
Easy access along footpaths from Craven Arms. All other facilities in
Craven Arms. |
LGS Yes. Shows changes of dominant fossils in different layers.
Structure visible in places. Easily accessible on footpaths and would
link with other exposures such as quarry at 444811 |
Fossils and Sedimentology/Stratigraphy |
| 0354 |
SO 453 856 |
Moorwood Scarp - Strefford
Wood |
Quarry |
Silurian: Wenlock Series: Tickwood Beds and Wenlock Limestone |
Series of quarries cut into top of scarp. View from this scarp to the
higher one formed by rocks of the Aymestry Group. |
Series of quarries running along the top of the prominent scarp just
west of Moorwood. Show the top of the Tickwood Beds and base of Wenlock
Limestone (ref.1). Largest is about 10 m high and 70 m long (to the R
of Forestry Commission sign); shows bands of nodular lmst separated by
siltstone partings less than 10 mm thick. Some layers show red
staining. Some jointing. Not obviously fossiliferous but some fossils
can be found in loose material. Smaller quarries (2 m high) lie to the
L (SW) of the sign. The beds here are thicker towards the base and
there is a smaller proportion of silly bands. More loose material with
more abundant fossils. Good place for a logging exercise. |
Easy access off Lower Dinchope to Westhope road at Moorwood. Parking in
the lane. Large area in front of main quarry if key for barrier can be
obtained. Vegetation makes access to the smaller quarries difficult. |
LGS Yes. A good sized site with obvious structures (even to those who
know nothing of geology) and changes in lithologies. In combination
with other sites down the scarp it allows a good understanding of the
rocks of the Wenlock Series. Very easy access and the one large face is
good for larger groups. |
Structure and Sedimentology/Stratigraphy |
| 0376 |
SO 479 864 (also 482 863) |
Upper Westhope
(S) |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group |
Quarry cut into side of steep scarp slope. |
Quarry with a max height of about 10 m shows at the base well bedded
limestones lenses (20-50 mm thick continuing laterally for 2 m or more)
separated and surrounded by sltst (individual beds <10 mm thick). Some
of the lmst appears very fossiliferous but fossils are very broken
(mostly crinoids?). Lmst becomes more nodular higher up the section but
is still the dominant lithology. Towards the top siltstone becomes
dominant with beds of fine sst. The top beds of the section are
inaccessible due to the steepness of the faces. The easterly dip means
a lot of different beds are accessible at the foot of the faces. There
is some loose material; more may be found beneath the brambles and other
vegetation. A good site for exercises such as logging. |
Accessible along bridleway from Westhope village next to a good sized
carpark (476862). The walk along here takes about 15 mins. |
LGS Yes. Good structure with change in lithologies throughout the
section. Dip means lots of beds are easily accessible. Easy access
with relatively parking nearby. Fossils can be found. |
Fossils and Sedimentology/Stratigraphy |
| 0403 |
SO 287 860 |
Cefn Einion - Mainstone |
Quarry (disused) |
Silurian: Cefn Einion Formation (probably equivalent to Lower Ludlow
Series) |
Large quarry cut into hillside |
Impressive large quarry (50 m by 20 m) showing good bedding structure
with dip 15° SW. Beds only accessible from the quarry floor except at
far S side (see later). Generally internal structure is very difficult
to spot but current bedding visible in fine sst at centre of back face.
Other areas weathered into cm blocks. Weathering picks out different
lithologies in the higher beds. Little loose material is visible but
there would be more beneath vegetation etc. at the foot of the faces.
There is a unofficial path up the south end from the road which leads up
to higher beds. These are generally thinner (20-50 mm thick). Still
fine sst and sltst but with possibly fewer fossils. Very fine shaley
partings which are not laterally continuous. (Allbutt:- ‘Surely type
locality for Cefn Einion Formation’). |
Private quarry which is fenced off; situated on R of road heading N from
Clun. Cottage immediately to the left was empty at the time of this
visit. Path at south end is not fenced. Room for a couple of cars to
park at the bottom of the drive to the cottage. |
LGS Yes. Type Locality. Important in recent re-mapping and
interpretations of this area (Allbutt). Good for large groups. Can
access top and bottom to give understanding of changes. |
Sedimentology/Stratigraphy |
| 0413 |
SO 274 981 |
Whittery Quarry - Chirbury |
Quarry (disused) |
Ordovician: Caradoc: Whittery Volcanics and Shales (ref.1). |
Quarry is cut into the top of the steep sided Marrington Dingle which
has been cut down by the River Camlad. |
The main feature of this quarry is the contact between the volcanics and
the shales; can be appreciated from a distance. The shales are thinly
bedded and lie above the much more massive units of the volcanics. The
quite steep westerly dip of the beds can be seen in the shales at the
far LH side of the quarry. Here they can be seen to fold under the
overhang created by tree roots. The volcanics are seen along the strike
and there was a constant leak of water out of the rock presumably
following the bedding surfaces. There are a few other small outcrops of
the shales and volcanics around the quarry but most of it is fully
vegetated. The main face has kept clear due to the steepness at which
it was cut. |
From Chirbury take a small lane just SE of the village off the A490
towards Hagley. Follow this up a steep hill and round a sharp bend.
The quarry is below the road (W) just after a small gap in the woodland
on this side. Park in the nearby enlarged gateways and follow the
footpaths down to the site. One path leaves the road to the N of the
quarry the steep faces of which are not fenced off from it so care must
be taken! |
LGS Yes. Clear demonstration of the conformable nature of the volcanics
and the shales. This site is FULL of rubbish which makes access to most
of the main face impossible. Steep loose banks make access to the rest
very difficult. However despite the rubbish that makes close inspection
impossible there is plenty to be gained from a distant look. (also see
new report in addeenda section below) |
Sedimentology/Stratigraphy |
| 0508 |
SO 356 998 |
Bergams Corner
- Worthen and Shelve |
Quarry (disused) |
Ordovician: Shelve Group: Mytton Flags and intrusive dolerite. |
On
bend in road with views north to North Shropshire Plain and closer to
steep valley sides e.g. Mytton Dingle (due to faulting?). |
This quarry face about 15 m high predominantly consisting of very dark
Mytton Flags. However in the extreme top right corner is the dolerite
intrusion as marked on BGS Shelve Ordovician Inlier map (1:25000). This
is a much stronger rock and has weathered to a brown colour. The loose
material it produces looks slightly different to that produced by the
Mytton Flags. The face is very steep and covered in loose scree which
makes reaching the top difficult but the difference in lithology can
just about be made out from the lay-by. The sedimentary rock here does
not appear to contain any obvious fossils. |
It
is on the inside of a tight right hand bend between Tankerville and
Stiperstones Village. There is plenty of space to park in front of the
exposure. Other facilities can be found in Stiperstones Village. |
LGS Yes. This has also been designated as an SSSI and as the rock is
still clear and easily accessible. |
Sedimentology/Stratigraphy |
| 0509 |
SO 359 928 |
Norbury Quarry |
Quarry (disused) |
Silurian: Llandovery Series: Pentamerus Sandstone (BGS Shelve Inlier;
1:25000). |
Small quarry cut into edge of valley bottom. |
The quarry itself is on private land and is in poor condition (very
overgrown and containing quite a lot of rubbish). There is a bit of
loose material; a lot of this shows a dense fauna either just on one
surface or (more often) in a dense bands a few cm thick. Most of the
fossils are just left as casts as the shells have dissolved. In the in
situ faces this results in a line of solution hollows that indicate
where the main fossil bands are. There are some signs of calcite
mineralization. The quarry is in a private field but there is a good if
small (0.3 m high x 3 m long) exposure on the road side where there is a
small pull-in just by the quarry about 20 m E of the gate. This shows
the beds dipping very gently to the S and has clear fossil bands in it.
There are further small exposures in the road side towards Norbury
(where stone walls are built of this material) and plenty of loose
material can be found along the verges. The hillside rising to the north
of this point is supposedly the site of Roman hushings whereby lead was
mined by sluicing with water ponded at the top of the hill (based on
rills revealed by aerial photographs taken with strong low angle light). |
The quarry is situated on the N side of the road. The field is private
so permission must be sought before entering the quarry (until his death
in 2006 this was from Mr Edwards at the farmhouse within Norbury
village). There is room for one car to park just E of the field gate;
otherwise park in a larger lay-by just along the road on the RHS towards
Norbury or in the village itself. |
LGS Yes. This is the classic location for the famous ‘Government Rock’.
The site gives a clear indication of the nature of the local
unconformity between Silurian and Precambrian sediments. The hillside
rising to the north of this point is supposedly the site of Roman hushings whereby lead was mined by sluicing with water ponded at the top
of the hill. |
Fossils and Sedimentology/Stratigraphy |
| 0702 |
SO 328 841 |
Bury Ditches
(N) |
Quarry (disused) |
Silurian: Ludlow Series (undivided) (BGS Wales Map 1:250000) |
Large quarry near the top of Sunny Hill from which there are good 360°
views interpreted with the aid of a toposcope. |
The face in Ludlow Series is quite impressive but difficult to reach due
to the vegetation. It is about 20 m high at the maximum and about 50 m
wide. It displays well bedded siltstone and fine sandstone with a
gentle dip. The beds are of quite regular thickness being 30 to 50 mm
thick and the whole exposure looks quite uniform. Due to the steepness
of the face and the angle of the dip only a limited number of beds can
be reached to see if this is really the case. The safest and easiest
bit to reach is to the right of the entrance where it is only a few
meters high and there are no dangerous overhangs. A few fossils were
found in the loose material in this area. There is little loose
material visible elsewhere but there is probably quite a bit under the
leaves and fallen branches. |
This is on the green way-marked route through the forest. Park at the
Forestry Commission carpark for Bury Ditches and take the main path up
and through the hill fort. Over the other side take the right hand
track at a T-junction. This track then passes the quarry entrance. |
LGS Yes. This is a large but very vegetated quarry on the N slope of
the hill. Considered as a LGS in conjunction with other sites in the
Bury Ditches area that show the different facies of this part of the
Ludlow Series. |
Mineralogy/Petrology |
| 0704 |
SJ 312 013 |
Meadowtown (NE) |
Quarry |
Ordovician: Llandeilo Series: Middleton Group: Meadowtown Formation (BGS
Shelve Area Map). |
This site is within an area made up of small valleys and associated
hills between the steep narrow Hope Valley to the E and the wider;
flatter Rea Brook valley to the W. This is on higher ground and gives
good views across the flat valley to the west and to other ridges etc to
the SW. |
The exposure reveals beds of two colours with some being much paler and
weaker than the rest. The beds are very even with no undulations or
obvious calcareous nodules and they have a steep dip to the NW. There
is abundant loose material. This shows the internal structure to be
slightly undulating. These pieces are also be the source of fossils.
Some pieces contained lots of fragmented pieces whilst at least one
complete trilobite pygidium was found on this visit. The site is only
quite small; about 10 m across with the faces up to 3 m high; but it is
very clear and open making it suitable for large groups. |
If
travelling from Rorrington (SW of Meadowtown) pass through the village
and take a track to the left once past the last of the houses. Follow
this around the contour of the hill to the left above the houses. The
site is on the R. There is no public access to this site and permission
should be sought from Meadowtown Farm. |
LGS Yes. Alternative to exposures at the SSSI of Meadowtown Quarry. It
is suitable for large groups and there is plenty of loose material to
work with. This site looks like quite a new excavation although it has
apparently been regularly used by Southampton University. |
Fossils and Sedimentology/Stratigraphy |
| 0705 |
SO 418 779 |
Shelderton - Clungunford |
Quarry (disused) |
Silurian: Ludlow Series: Aymestry Group. |
Quarried limestone makes a prominent feature on the side of this wooded
hill. It forms a V on the map as it crosses the small valley down which
the road runs as well as a few other small quarries in the hillside of
which this is one. |
This is the highest of the quarries along this road and is just a few
10's of meters above the other quarries (Shelderton Rock and Swan Hill)
to which this is compared. In this top quarry the rock has a much more
flaggy nature with more continuous siltstone beds rather than limestone
nodules. The beds are thicker here; up to 150 mm thick. The rock is
still quite calcareous in places; with some bands having a chalky
texture; but there is definitely a much higher percentage of siltstone
in these higher beds. There is lots of loose material but here it is
only sparsely fossiliferous with the odd brachiopod being found. The
lowest beds in this quarry are still slightly nodular so this could show
a transition from the limestone facies into the Upper Ludlow Shales??
There is a further small outcrop about 3 m high and 4 m long in the
roadside just above this quarry which shows some very flaggy material. |
This quarry is situated on a minor road between Shelderton and Onibury
as marked on the Ludlow OS Pathfinder map No. 951 (SO47/57). The quarry
is on the S side of the road (on the R when travelling uphill from
Shelderton). Parking is limited to the verges which are a reasonable
width in places but can be quite soft. This quarry is fenced off from
the road but there is a gate (padlocked on this visit). Care must be
taken if there is any sign of forestry operations. |
LGS Yes. Included in a large site that takes in Shelderton Rock and
Swan Hill quarries that are just below it. As a group of sites they
provide ample material to study the limestone facies and the transition
to much siltier material as the higher beds are reached. They are easily
accessible and suitable for large groups. |
Mineralogy/Petrology |
| 0707 |
SO 504 745 and SO 506 744 to 512 741 |
Whitcliffe (W)
and Teme Bank |
Quarry (disused) |
Silurian: Ludlow Series: Whitcliffe Beds. |
Huge quarry cut into hillside towards the top of Whitcliffe plus
excavations for the Bread Walk footpath just above the river. |
A
series of small rock faces along the Bread Walk (max height generally 2
m) show well bedded sltst with some more calcareous layers. Beds 10-100
mm thick gently dipping to NW. Some internal bedding visible. Most of
the loose material contained fossils in thin layers which included many
genera of brachiopods; bivalves; bryazoans and ostracods. Some of the
fossil layers were visible in the rock faces. Along the River Teme bank
and up Whitcliffe there are a number of exposures and larger quarry
faces along all the upper paths through the wood and along the river.
These show structures such as solution hollows; current bedding; fossil
lenses; spheroidal weathering; bioturbation. Lithologies vary in the
different layers which range from fine friable siltstones to fine
sandstones and calcareous sandstone and siltstone. Bedding thickness
range from mm scale to 500 mm. Dips indicate a slight anticlinal
structure with beds dipping NW at the west end of Whitcliffe and East at
the east end. The largest single exposure is in the main quarry just
above the rock-cut steps in the Bread Walk. This extends for ca. 200 m
along a small path and the main face is about 15 m high. The path goes
uphill slightly allowing several of the beds to be examined closely.
This is also a good source of fossiliferous debris showing brachiopods;
crinoids and occasional in-filled burrows. The higher exposures are
unsafe and small rockfalls frequently occur especially after frost
thaws. |
Parking along the road leading to Mortimer Forest and the higher ground
above Whitcliffe. |
LGS Yes. Easy access to the higher beds in the sequence which may not
be visible elsewhere. |
Sedimentology/Stratigraphy |
| 0710 |
SO 394 875 |
Hillend Cottage (E) -
Lydbury North |
Natural exposure |
Silurian: Llandovery Series (Upper): Pentamerus Beds. |
Small exposure off road at base of hillside. |
This is a good exposure of Pentamerus Beds dipping quite steeply SE
which shows the fossil bands very clearly especially near the bottom of
the outcrop and another about 1.6 m up the section. It also shows the
other lithologies in these beds. The fossils are still predominantly
calcified. There is plenty of fossiliferous loose material. Also in the
talus were other rock types including grey sandstone with calcite veins;
and a few pieces of hard; purple slate-like shale. It shows a much
clearer structure than a lot of the other sites along this road
including the SSSI (Hillend) about 300 m E. The dumping of the previous
report has been cleared. |
Park at the lay-by about 400 m SW of this exposure. The outcrop is just
up a track on the N side of the A489 over a derelict wooden gate. The
exposure can be seen quite clearly from the road. |
LGS Yes. Shows clearly the structure of the rocks and the fossils that
give this rock its name (Pentamerus Beds). It has easy access and plenty
of loose material to study. |
Fossils |
| 0713 |
SO 420 854 |
Onny Valley (old river
cliff) - Wistanstow |
Cliff |
Ordovician: Caradoc: Cheney Longville Flags. |
Old river cliff; about 50 m away from present river line. |
Well bedded Cheney Longville Flags containing fossils such as
tentaculites and brachiopods and bedding features such as hummocky
bedding. The bottom section can be reached around the back of the bog
which wasn't too wet at the time of this visit. However this area has a
few dangerous overhangs. The other area is above the first up the farm
track. Here the exposure is not so good but it is safer. There is more
loose material on the farm track than below where it has probably sunk
into the bog; but there is more vegetation at the top. The different
lithologies (sltst; sst and mudstone) can be seen in either area. |
This is just off the permissive footpath that runs along the valley. It
is on the N side and is reached over a stile in the fence off the old
railway track. It is best to park in the car park on the Cheney
Longville road (SO428845) and walk along the river. |
LGS Yes. This exposure is found to the N of the railway line behind a
boggy patch of ground. Designated as part of a larger site encompassing
the whole of the river as outlined in the attached note (Word file
name:- Onny Valley LGS). |
Fossils and Sedimentology/Stratigraphy |
| 0714 |
SO 417 857 |
River Onny
(railway) |
Cutting (road/railway) |
Ordovician: Caradoc: Chatwall Sandstone (highest). |
Old railway cutting. |
This site is right on the side of the old railway and as it is only a
few metres high it is all easy to reach. There are local variations in
dip but all beds are dipping to the SE. Shell bands can be seen in the
in situ rock and there are plenty of fossils in the loose material. It
is suggested that the change in dip is due to changing storm conditions
(ref.1). |
This is along the permissive path that follows the old Bishops Castle
Railway line from a carpark west of Cheney Longville to Glenburrell.
Therefore this site can be approached from either end but parking is
much better at the E end. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Fossils and Sedimentology/Stratigraphy |
| 0715 |
SO 413 860 |
Glenburrell
railway bridge |
Cutting (road/railway) |
Ordovician: Caradoc: Chatwall Sandstone. |
Cutting on S side of old railway track running along side the river. |
A
long (50 m) exposure which is on the W side of the Church Stretton (F3)
fault. The faulting is responsible for the steep dip (85°SE) at this
locality compared to about almost horizontal bedding that is seen a few
hundred meters further east. In these mainly medium grained sandstone
beds some structures are visible such as current bedding indicative of
storm conditions. This is a good exposure with easy and safe access.
There is a further exposure of Chatwall Sandstone that shows the typical
purple banding better (Locality 3 in ref.1). This is found to the E up
the bank in the trees; however it is not easily accessible. Under the
railway bridge there are small stalactites made from water percolating
through the mortar of the bridge. |
This is along the permissive path that follows the old Bishops Castle
Railway line from a car park west of Cheney Longville to Glenburrell.
Therefore this site can be approached from either end but parking is
much better at the E end. |
LGS Yes. Designated as part of a larger site encompassing the whole of
the river as outlined in the attached note (Word file name:- Onny Valley
LGS). |
Sedimentology/Stratigraphy |
| 0800 |
SJ 553 035 to SJ 559 036 |
Coundmoor Track - Cound |
Track/roadside |
Main exposure is Precambrian (Uriconian Volcanics) but there are small
exposures of Ordovician (Hoar Edge Grit and Harnage Shale; Caradoc
Series) and what appears to be Lower Ordovician (Sheinton Shale;
Tremadoc). |
Exposure of Precambrian forms a small bluff along the track while the
others are trackside exposures in a wooded valley drained by the
Coundmoor brook. |
Main exposure of Uriconian Volcanics is generally rhyolitic with some
more basic rock. The rock is badly weathered and rotten with evidence of
being broken by faulting. On the right of the exposure the rock looks as
if it is bedded vertically but this is probably the result of faulting
and it is part of a shear zone. Here; there is considerable hematite
staining. The exposure continues above the main face for another 2-3 m
but the rock is covered with ivy and no detail can be seen. Along the
track towards Cound (Eastward); Hoar Edge Grit is exposed and near the
foot bridge and confluence (SJ 559036) there is a good exposure of a
different; probably Sheinton Shale. |
Track becomes a public footpath a few metres beyond the Uriconian
Volcanics exposure. Access is easy and one can examine the rocks close
at hand. Parking is limited to two cars at the ford (SJ553034). |
LGS Yes. Designated a LGS on account of its vivid demonstration of the
effect of the Church Stretton fault system in bringing into
juxtaposition many rock units of different age and lithology. |
Structure and Stratigraphy/Stratigraphy |
| 0803 |
SJ 558 034 to 559 037 |
Coundmoor Brook - Cound |
Stream/brook |
Upper Ordovician: Caradoc Series: Harnage Shale. |
Brook meanders along a narrow valley then through woodland. |
There are several bank exposures of Harnage Shale and some in the stream
bed. At the W end of the SSSI; about 40 m from an old bridge built of
Hoar Edge Grit; is a bankside exposure of grey shale; water seeps out
and flows over it as a small waterfall. The shale is finely laminated;
soft and shows vertical and over-turned bedding. A few metres away the
dip has lessened to approx. 40°. There is evidence of brecciation. All
this points to effects of the Church Stretton fault system. Upstream 100
m is another shale exposure under the roots of an oak tree; which can be
seen crossing the bed of the brook. Here the dip is 54° NW. The SSSI
continues further downstream and exposures in the stream bed were
examined at SJ 559037 where the Harnage Shale is still outcropping. Here
the beds can be seen dipping below water level and are best examined by
wading along the brook. |
Easy access from the public footpath. Limited parking at the ford
(SJ553034). Otherwise approach from Cound Church. |
LGS Yes. This is a nationally important geological site providing
exposures of fossiliferous rock of Ordovician age. The stream exposures
are regarded as the standard or type-section for the Harnagian stage of
the Ordovician. During this stage; this area lay on the eastern edge of
a deep ocean basin covering Wales while shallower shelf environments lay
to the east. Fossil organisms characteristic of both environments are
found at this site; allowing detailed comparisons to be made. In
addition; a number of species of trilobites were first collected and
described from this locality. |
Fossils and Sedimentology/Stratigraphy |
| 0805 |
SJ 604 082 |
Rushton - Wroxeter |
Track/roadside |
Precambrian: Rushton Schists. Special Sheet 60 - Telford. |
Not applicable. Exposure is a small flat feature on the level ground in
Rushton village about a kilometre from the Wrekin. |
Exposures of Rushton Schists are rare and this one is revealed by
erosion and weathering. The amount of rock visible is limited to an
irregular surface outcrop. A finely laminated fine-grained dark
olive-grey schist is visible with quartz; plagioclase and chlorite.
Foliations can be seen. This is inter-bedded with more massive; pink;
quartz- feldspar rocks which are said to contain garnet and epidote.
There is evidence of quartz veining. These rocks were originally gritty
shales and flags deposited in quiet waters and subsequently regionally
metamorphosed to a low/medium grade. Compared by Dearnley to the Mona
Complex of Anglesey. |
Public road. |
LGS Yes. Although a limited site; it is one of very few easily
accessible Rushton Schists exposures. As one can examine the rock
readily and as these represent the oldest rocks of Shropshire. |
Mineralogy/Petrology |
| 0807 |
SJ 608 001 to 609 000 |
Wenlock Edge
(N) (Edgefield Quarry) |
Quarry (disused) |
Silurian: Wenlock Limestone (reef facies). Special Sheet 60 - Telford. |
Forms a gorge cutting across the crest of Wenlock Edge. |
This is an excellent site; a large disused quarry displaying a range of
reef features in the context of surrounding bedded limestone. Next to
the footpath there is a prominent exposure of nodular limestone with
slabs of near horizontal limestone projecting from it. Height of face
here approx. 8 m. To the left (SE); nodular limestone passes into more
regular bedded rock with clay partings. The limestone is coarsely
crystalline; often crinoidal; and examination of the fallen fragments
revealed compound corals; small brachiopods and bryozoa. The exposure
continues for about 200 m being accessible by a path along the gorge. At
the far end there is a magnificent face showing ballstones inter-bedded
with nodular and flaggy limestones. Thin beds can be seen above and
dipping off the ballstone mass. A recess 2 m from the bottom marks a
clay layer; possibly bentonite. Great limestone slabs overhang at the
top of the face which is here about 10 m high. |
Via public footpath from Harley Hill or Much Wenlock. |
LGS Yes. LGS on the grounds of the range of features characteristic of
the Wenlock Reef Facies; the easy access; its potential educational
value; and the impressive beauty of the site. |
Fossils and Sedimentology/Stratigraphy |
| 0808 |
SJ 6100 0035 |
Harley Hill Quarry - Much
Wenlock |
Cutting (road/railway) |
Silurian: Wenlock Series: Tickwood Beds (Special Sheet 60 - Telford);
now known as the Farley Member. These are beds transitional between
Coalbrookdale Formation and Much Wenlock Formation. |
Site is part of an impressive road cutting where the A458 goes through
the escarpment of Wenlock Edge. |
The section comprises 15-25 m of grey; shaly mudstones with numerous
prominent limestone nodules often forming bands. Fossils were not easy
to find despite written references to the presence of large brachiopods;
e.g. Eospirifer radiatus and Meristina obtusa (which suggest the sea was
shallower than in Coalbrookdale Formation times; thus emphasising the
transitional nature of the rocks at this site). There are several
prominent vertical joints and two distinct recessed clay horizons near
the base of the section. These weather to a brownish colour and are
probably bentonite layers. Towards the west end of the quarry the
bentonite layers are displaced by approx 3 m by what appears to be a
fault. The lower part of the face has fewer nodules and beds are more
irregular. Ascending the sequence; the nodules become more calcareous
and begin to 'fuse' into definite layers. This is an indication that the
conditions were becoming more suitable for limestone formation and the
Farley Member passes upward into the Much Wenlock Formation. It is
written that the lower boundary of the latter is located where
calcareous nodules coalesce into limestone beds. It is not easy to
locate this boundary with conviction. |
This site is next to an extremely busy road and to approach on foot can
be hazardous. Not to be recommended for large groups or school parties.
Parking is very limited; there being two places where a single car might
pull in. |
LGS Yes. This is clearly an interesting and important site and although
its importance has been reduced a little by the newer Farley Dingle road
cutting; it still shows very effectively the characteristics of the
transitional Farley Member of the Wenlock Series. |
Sedimentology/Stratigraphy |
| 0812 |
SJ 619 020 |
Whitwell Coppice - Homer |
Stream/brook |
Silurian: Wenlock Shale: Homerian Stage; Whitwell chronozone; Upper
Coalbrookdale Formation. ('Geology of Telford and the Coalbrookdale
Coalfield. Special Sheet 60 - Telford.) |
Next to a tufaceous waterfall where the stream (a tributary of the
Sheinton Brook) cuts a gorge into the hillside in the coppice. |
A
fairly extensive stream section with several exposures in the bank and
in the stream bed of soft; grey shale with near horizontal bedding.
Weathers to a sticky mud. An interesting aspect of this site is the
amount of tufa visible on twigs; rock fragments and at the small
waterfall. The shale is distinctly fossiliferous; fragments of
cephalopods and a good specimen of Dalmanites caudatus were found almost
straight away. Benthonic forms are relatively scarce which suggests a
deeper marine environment than that of the underlying Buildwas Beds. |
Necessitates a walk of approx. 200 m through the Coppice off the public
footpath. This was fairly easy on the day of the survey (14/1/00) but a
summer visit would present problems of brambles and tangled
undergrowth. Suitable for only very small groups especially as there is
only room for one car to park on the roadside at Whitwell. |
LGS Yes. This site is already a SSSI and recognised as the standard
reference section for the base of the Homerian Stage in the middle of
the Coalbrookdale Formation (Wenlock Shale) of the Silurian System. It
is defined by appearance of the zone fossil Cyrtograptus lundgreni. |
Sedimentology/Stratigraphy |
| 0817 |
SJ 624 008 |
Windmill Hill - Much
Wenlock |
Quarry (disused) |
Silurian: Wenlock Limestone. Special Sheet 60 - Telford. |
At
the base of a hill with remains of old windmill. Hill is a prominent
landmark in the town. |
Rocks exposed here are bedded Wenlock Limestones; mostly crinoidal. The
faces are to some extent obscured by weathering but display clearly both
nodular and flaggy beds. A definite recessed softer horizon is
emphasised by differential weathering. This is clayey in character.
Bedding planes appear to be wavy as a result of the nodules and dip
generally NW. In the NW corner is a prominent fault or joint plane (not
easy to decide which) with tufa deposits. The quarry provides good
examples of true and apparent dip. Height of exposure is 3-4 m and the
width of the quarry is approx. 20 m. On the ground were rock fragments
containing a range of typical reef facies fossils e.g. Favosites
gothlandicus; Heliolites interstinctus; Acervularia ananas; and various
brachiopods. Some evidence of stromotoporoids as well as crinoids was
found; and on the back face possible striations were seen. There is a
distinct boundary at the bottom of the back face which seems to mark the
change from reef facies to more bedded limestone. |
Good. Next to public footpath close to the town where there is
car-parking.. |
LGS Yes. LGS mainly because it is a convenient site for school or
university groups to examine easily both the reef facies of Wenlock
Limestone and the bedded limestone; collect fossil material and carry
out dip and strike exercises as well as identifying structures and
evidence of calcite mineralisation. |
Sedimentology/Stratigraphy |
| 0820 |
SJ 627 079 |
Wrekin Hill |
Natural exposure |
Mostly Precambrian (Uriconian Volcanics) with Cambrian (Wrekin
Quartzite) on the SE flanks. (Special Sheet 60 - Telford.) |
The Wrekin Hill stands prominently out of the surrounding plain to a
height of 407 m. Striking towering mass of rhyolite with a deep cleft |
Apart from the summit rhyolites the exposures although numerous are
small but there is a wide variety of Uriconian tuffs agglomerates and
rhyolites which can be examined easily. The summit rhyolites are pink;
often flow-banded and sometimes spherulitic.The Needle's Eye is one of
several rhyolite outcrops on the summit ridge of the Wrekin. The
rhyolites are heavily brecciated and fragmented; described as explosion
breccias; formed during violent volcanic events. This makes up part of
the series of rhyolite flows forming the central mass of the Wrekin. The
rock of the Needle's Eye is described by Pocock as a rhyolite
'devitrified to a micro-felsitic intergrowth of quartz and feldspar;
with incipient spherulitic structures'. It is veined with secondary
silica. The rock at the Raven's Bowl and Bladder Stone is probably from
the same flow. At the Needle's Eye there is little flow-banding; instead
the rhyolites show characteristics of auto-brecciation (a clear
indication of the explosive nature of the volcanic environment).
Elsewhere many basic dykes are visible along the main route to the top.
At the foot of the Wrekin; and along the main path several exposures of
tuffs and Cambrian quartzite are exposed. Up to 1500 m of tuffs and
lavas occur on the Wrekin and the rocks are considered to have
originated during a prolonged episode of explosive volcanic activity in
an island arc environment in the Late Precambrian. |
Open access. |
LGS Yes. LGS status in its own right as well as being part of the
whole Wrekin LGS site. The rhyolites can be examined easily and
compared with other rhyolites and tuffs of the summit area. However it
may be decided that designation of the Wrekin in its entirety is
sufficient. Designated a LGS as the type section for the Uriconian
volcanic suite of lavas an pyroclastics and associated with the Ercall
and Lawrence Hill as an outstanding example of a faulted inlier. It is a
unique location where a range of Precambrian lavas and pyroclastics can
be easily studied. In association with the Ercall and Lawrence Hill; the
Wrekin provides an outstanding example of a faulted inlier of
Precambrian igneous rocks. |
Mineralogy/Petrology |
| 0825 |
SJ 637 026 |
Farley Dingle |
Cutting (road/railway) |
Silurian: Farley Member (Tickwood Beds); Special Sheet 60 - Telford and
Telford memoir. |
Road cutting between Farley Coppice and Tickwood which form the Northern
extension of Wenlock Edge. |
The site comprises a cutting through the A4169 at Farley Dingle This is
approx. 200 m in length and reaches a max. height of 30 m with a steep 1
in 2 slope; the section has been stepped to allow access at different
levels. The sequence of rocks form a series of relatively soft mudstones
and shales; grey; weathering to olive; at the base of the sequence with
bands of nodules becoming more frequent higher up. The nodules become
more obviously limy higher up and begin to resemble typical Wenlock
Limestone. The mudstones and shales form the upper part of the
Coalbrookdale Formation and the top of the section can be described as
Much Wenlock Formation. In between the rocks show transitional
characteristics and are known as the Farley Member. One of the terraces
has been cut approx. along the Coalbrookdale/Farley boundary. At this
site; the Farley member is considered the most representative and best
exposure of rocks of this age in the country. The Farley Member reflects
the gradually changing environment existing 425 Ma when deep seas
leading to accumulation of muds and silts shallowed and cleared
sufficiently to allow the formation of limestones and the fossiliferous
reefs of Wenlock Edge during the Silurian. Fauna is not abundant but;
in contrast to the underlying strata; the Farley beds contain large
brachiopods; including Atrypa reticularis; Eospirifer radiatus;
Meristina obtusa and Gypidula galeata; suggesting a shallower sea floor. |
Site flanks a busy main road (A4169) where parking is not possible.
Walking to the site along the same main road again is not pleasant.
However; just below the rock face is a concreted drainage channel which
provides useful access to the lower part of the section. A terrace has
been cut to allow access to the upper part of the section but this is
not for the faint-hearted or anyone suffering from vertigo. Not a site
for school parties! |
LGS Yes. This site was selected by the Geological Conservation Review
as an SSSI and forms part of the 'Wenlock' subject block. Farley Dingle
SSSI provides a unique locality where the transition between
shale/mudstone lithology of the Coalbrookdale formation and overlying
Wenlock Limestone can be studied. |
Sedimentology/Stratigraphy |
| 0827 |
SJ 638 093 |
Lawrence Hill
(Forest Glen) Quarrry |
Quarry (disused) |
Precambrian: Uriconian Volcanics. Special Sheet 60 - Telford. |
Spectacular cliff in the Forest Glen between Wrekin and Ercall Hills. |
The quarry lies to the south end of the Ercall and Lawrence Hills
opposite the Wrekin. It consists of two embayments separated by three
near-vertical NE/SW- trending dykes of basalt which appear to follow
faults. The middle dyke is most easily examined and forms a prominent
rib. The contact with surrounding pyroclastic rocks is visible. The main
face consists of Precambrian tuffs and agglomerates belonging to the
Uriconian Volcanics and these are seen to dip approx N at an angle of
45°. The tuffs display variable textures with definite coarser
agglomerates inter-bedded with lithic and vitric rhyolitic tuffs.
Irregular jointing and slickensiding characterise the quarry faces. |
Open access as the site backs onto a car park on the road through Forest
Glen from Wellington to Little Wenlock. |
LGS Yes. LGS as an exemplary exposure of a sequence of Precambrian
volcanic tuffs (and lava) which merits classification as a type section
for that strata and which would be an essential exposure in any future
research carried out on Precambrian volcanic rocks. |
Mineralogy/Petrology |
| 0831 |
SJ 647 042 |
Buildwas Sand Quarry -
Buildwas |
Quarry (working) |
Pleistocene sands and gravels; mostly Bunter-derived (Special Sheet 60 -
Telford.) |
On
southern bank of River Severn as it enters Ironbridge Gorge. |
Buildwas sands are deposited in thin cross-stratified units and largely
consist of clean Permo-Triassic derived sands with scattered clasts
often of coal debris. These sands are overlain unconformably here by
coarse assorted gravels which pass upwards into a till. The sands are
well-sorted; red/brown in colour and of 'millet seed' texture. It is
the back face of the now unworked part of the quarry which displays the
sands and gravels best and it is possible to approach closely. The
gravels in the middle of the back face are extremely coarse in places
with clasts up to 0.2 m long; the size increasing higher up the face.
There is some confusion at the top of this face because the topmost
deposits of till appear to contain clinker and other non-naturally
produced debris. The discovery that an old railway line used to run
along the top of this face may explain some of the anomalies. For a good
exposure of till with pebbles it is best to climb the North face and
walk along a path at the top. The deposits are interpreted as fluvio-glacial
and the numerous cut and fill structures are thought to have formed in
braided streams of low sinuosity. |
Permission needed. Report to office to sign in. |
LGS Yes. A very important Quaternary site with links to interpreting
the nature and formation of the Ironbridge Gorge. Examples of varied
fluvio-glacial sands and gravels as well as the clearly exposed till. |
Sedimentology/Stratigraphy |
| 0832 |
SJ 665 058 |
Jiggers Bank -
Coalbrookdale |
Cliff |
Upper Carboniferous: Lower Coal Measures. Special Sheet 60 - Telford. |
Part of the steep side of Coalbrookdale as it descends into the
Ironbridge Gorge. |
An
impressive exposure of mostly Carboniferous sandstone; grey/buff
weathering orange; which has some massive bedding showing
cross-stratification. This distinctive layer is at the top of the
section and is about 6-7 m thick. The base of this horizon is a coarse
conglomerate. In places there is a projecting overhang below which is a
more flaggy; thinner layer (1.5 m) of sandstone. This passes downward
into a more broken sandstone layer before passing into grey; laminated
sandy shale containing many carbonaceous fragments. The dip can be
clearly seen to be approx. NNE. By walking a few metres along the
Crackshall footpath a continuation of the exposure can be seen and
examined. This is hidden by trees in summer. The rocks here are
representative of a poorly drained delta plain. |
Site is readily accessible as it lies beside a public footpath. Limited
parking is possible about 200 m down the hill but the walk to the site
is along a busy road; Jigger's Bank. |
LGS Yes. A very good exposure of Lower Coal Measures; illustrating
variation in sedimentation according to changing environmental
conditions within a deltaic setting. A striking example with reasonable
access. |
Sedimentology/Stratigraphy |
| 0834 |
SJ 675 068 |
Doseley Quarry |
Quarry (disused) |
Lower Carboniferous: Dinantian: Little Wenlock Basalt. Special Sheet 60
- Telford. |
Forms the back wall of an infilled and partly flooded old quarry; in the
middle of Doseley. |
Basaltic columns rise to approx.12-14 m behind a pool; forming the back
wall of the old quarry. Strong horizontal joints cross each of the
columns. Between the columns orange soil of weathered basalt is visible
and to the right; a deep red ochre can be seen where the iron minerals
have weathered out. To the right of the main face are two thick beds of
overlying Coal Measure Sandstone resting unconformably on the basalt;
dipping NE. Near to the reception offices beside the track there are
exposures of leaning columns and excellent examples of spheroidal
weathering. These can be examined at close hand. |
Cannot approach the columns of basalt on the back wall of the quarry |
LGS Yes. This is probably the best example in the County of the Little Wenlock Basalt showing columnar structures. It is already an SSSI. |
Mineralogy/Petrology |
| 0835 |
SJ 676 005 to SO 705 989 |
Dean Brook |
Bank |
Quaternary - Geomorphological site |
Steep-sided narrow valley. |
An
interesting valley as the Dean Brook probably formed the head-waters of
the Severn before the cutting of the Ironbridge Gorge. It joins the
Severn now opposite the Main Terrace deposits of Apley Lawn; which are
the furthest upstream Main Terrace deposits on the Severn. At the
present source of the brook between The Vineyards and Dean Corner;
glacial till is often overlain by patches of sand and gravels forming
knolls. |
Mostly on private land but the main features can be seen from footpaths
and public roads. |
LGS Yes. Recommended as a geomorphological LGS on account of its
importance in the development of the course of the Severn and Quaternary
events related to the cutting of Ironbridge Gorge. Hamblin favours the
Dean brook as the place of a stillstand as the ice-Sheet retreated from
the Bridgnorth to Wolverhampton line to that of Ironbridge Gorge. |
Geomorphology/Landscape |
| 0838 |
SJ 683 117 |
New Hadley
Brickpit |
Quarry (working) |
Carboniferous: Upper Coal Measures: Hadley Formation. |
Changes according to the current work in the pit. |
The site is a face within the working clay pit. Its thickness is approx.
34 m but not all is readily visible. The rock is Etruria-type mudstone;
with espleys. The mudstone is mainly purple-brown; unbedded and in
places mottled. The espleys are easy to identify; being best described
as a fine breccia with angular fragments of Uriconian igneous material;
feldspar; Coal Measures sandstone; and shale clasts in a matrix of
angular coarse sand. Sharp erosional bases can be seen cutting into the
underlying mudstone; reflecting channelling by flood waters from a
relatively close upland source. Espleys are therefore lenticular
channel-fill deposits; 30-40 m wide and commonly aligned NW/SE.
Overlying the Hadley Formation are the grey mudstones representing the
seat earth of the Main Sulphur Coal. |
Via reception area at Blockley's with prior permission. |
LGS Yes. The sediments here are representative of alluvial fans at the
margin of the basin of deposition. Such marginal deposits in the Hadley
Formation are virtually confined to this area and this is the only site
where they can be clearly demonstrated. A site of outstanding importance
for interpreting the geological history of the Late Carboniferous in
Britain. |
Sedimentology/Stratigraphy |
| 0840 |
SJ 690 023 |
Corbetts Dingle - Broseley |
Natural exposure |
Upper Carboniferous: Upper Coal Measures: Coalport Formation. Special
Sheet 60 - Telford. |
Gorge-like valley eroded along the Corbett Fault. |
Impressive exposure of mainly sandstones either side of a deeply cut
brook. The grey-buff sandstones tower 12 m or so above the footpath and
display abundant cross-stratification and spheroidally weathered
iron-rich nodules. The sandstones are exposed for about 300 m along the
main dingle but there are more in the tributary valley. It is therefore
a large site and would benefit from more detailed study. Some beds are
massive; up to one metre thick; while others are more flaggy. Dip of
strata is about 18° NW but the effect of the fault steepens the dip;
especially in the tributary valley. Faulting has caused a downthrow and
displacement of sandstones and breccia beds of 10 m to the west. |
A
public footpath follows the dingle and close up examination of the site
can be carried out. Approach either from The Tuckies by R. Severn or
from the Ironbridge road; Broseley. |
LGS Yes. Splendid site with much educational value on account of its
being able to accommodate a large group and be easy of access. The
sandstones with many sedimentary structures representing part of the Coalport Formation and the excellent example of a fault-guided valley
present a strong case for LGS. |
Structure and Sedimentology/Stratigraphy |
| 0842 |
SO 728 934 |
The Hermitage - Bridgnorth |
Quarry (disused) |
Permian (Bridgnorth Sandstone) and Lower Triassic (Kidderminster
Conglomerate). Dudley and Bridgnorth 1967. New names from Telford Sheet. |
Recessed cliff with evidence of cave habitation. The conglomerate forms
roof of medieval (?) dwelling. |
This is a striking exposure of the wind-blown Bridgnorth Sandstone with
its clear cross-bedded units reflecting a desert environment. It is
possible to reach the face to examine the texture of the millet-seed and
grains and the nature of the dune bedding. The rock is uniformly
fine-grained and red-brown in colour. Cement is scanty and although the
rock stands up well as a cliff face it crumbles readily. Dip of beds is
about 7° E. The Kidderminster Conglomerate has large rather angular
clasts of Carboniferous Limestone marl and quartzite with scattered
pebbles of igneous origin held in a coarse sandy matrix (Dudley &
Bridgnorth Memoir; 1947). This represents the basal unit of the Lower
Triassic. Deposited by a major north-flowing river system during flash
floods in a semi-arid climate. It rests unconformably on an eroded
Permian surface. Queen's Parlour on Wolverhampton Road is directly
adjacent to The Hermitage. The exposure is some 50 metres long by 15
metres high. The base of this exposure comprises the Lower Mottled
Sandstone (5 to 6 m deep) - a medium to fine grained rock displaying
some dune bedding and believed to have been lain down in aeolian
conditions. This is overlain by the Bunter Pebble Beds ( 7 to 8 m deep)
consisting of a conglomerate composed of angular and subrounded pebbles
(30 to 40 mm). The Bunter Pebble Beds are considered fluviatile in
origin and the contents vary. |
Via steps and footpath from A454. Some barbed-wire obstacles. After
about 1 mile there is a small traffic island and some 50 m from the
Bridgnorth side of the Island on the left hand side of the road there is
a small `pull in' suitable for possibly two vehicles. From there retrace
route back towards Bridgnorth via a footpath along the side of the road.
After about 200 m an exposure of conglomerates is clearly evident.
About 20 m below this exposure and on the other side of the road a
footpath sign is just visible. Cross the road and take a well trodden
footpath which after about 30 m will lead to a sandstone and
conglomerate exposure. This is The Hermitage and is adjacent and to the
right of the Queen's Parlour. Access is reasonable. However the crossing
of the main Wolverhampton Road at this point is not for the faint
hearted. It is a short and easy walk to the outcrop from the main road. |
LGS Yes. Spectacular example of an erosion surface in the upper part of
the Bridgnorth Sandstone overlain by Kidderminster conglomerate. Shows
clear evidence of changing environment from desert to flash floods. |
Sedimentology/Stratigraphy |
| 0843 |
SO 727 935 |
Hermitage Hill - Worfield |
Cutting (road/railway) |
Permian (Bridgnorth Sandstone) and Lower Triassic (Kidderminster
Conglomerate). Bridgnorth and Dudley map 167. |
A454 road cuts through the rock exposing strata each side. |
A
small exposure of Bridgnorth Sandstone at the western end of the cutting
passes into a good section through the Kidderminster Conglomerate. Large
pebbles of quartzite Carboniferous Limestone marl and igneous rocks are
held in a sandy matrix made stronger by a calcite or silica cement.
Evidence of alignment and cross-stratification can be seen. The clasts
become less continuous higher up when the proportion of sand (fine and
less bright than the Bridgnorth Sandstone) increases. Pebbles scattered
in approximate layers and more randomly (smaller); cross-stratification
in the sandstone; generally agreed to be fluvial. An interesting feature
is the good example of channelling towards the E. end of the cutting and
high up in the face. |
Exposure is on a main road but there is a footpath. Traffic noisy and
dangerous. |
LGS Yes. Despite the main road this site is valuable when studied with
SO728934 (The Hermitage). It is higher in the sequence and although a
little Bridgnorth Sandstone is visible the main interest lies in the
Kidderminster Conglomerate which passes upwards from being coarsely
conglomeratic into fluvial sandstones with evidence of channelling. |
Sedimentology/Stratigraphy |
| 0845 |
SJ 539 143 (fence of quarry moved; exact position difficult) |
Haughmond Hill
(W) - Uffington |
Natural exposure |
Precambrian: Wentnor Group: Bayston-Oakswood Formation: Darnford
Conglomerate. Sheet 152. |
On
west slope of Haughmond Hill near the top. |
Southwest of the main working quarry; beyond the perimeter fence are
several small exposures of Darnford Conglomerate showing orientation of
pebbles parallel to the vertical dip. By the footpath which runs along
the west boundary of the working quarry are more small exposures.
Pebbles are often very small (2 mm) but there are coarser bands with
pebble up to 10 mm across. The N-S orientation of the pebbles reflects
the same trend of the strata which are always nearly vertical. Some
quartz mineralisation was seen on the surface and structures resembling
slickensides. A little further north a wall-like exposure can be seen;
3 m across and one metre high. Although it at first looks artificial; on
closer examination it appears to be a vertical exposure of very coarse;
poorly sorted grit with a variety of clasts; some being green and others
black. This reflects the presence of iron minerals and chlorite;
mentioned by Pocock. This exposure is crossed by regular joints at right
angles to each other and appears to consist of rectilinear blocks about
0.1 m across. This seems to mark the boundary between the grits and
conglomerate; the latter being exposed only a few metres away along the
footpath. |
Mostly along a public footpath but the grit exposure is just the other
side of the perimeter fence. |
LGS Yes. Designation because this is a striking example of the coarse
grit adjacent to the Darnford Conglomerate; both being conformable
members of the Bayston-Oakswood Formation. The boundary between the two
rock types seems to be here and the site can be reached without going
into the main quarry. Also these exposures should be seen in the
context of the geology of the whole of Haughmond Hill. |
Mineralogy/Petrology |
| 0847 |
SJ 545 165 |
Ebury Hill - Uffington |
Quarry (disused) |
Precambrian: Wentnor Group: Bayston-Oakswood Formation: Darnford
Conglomerate. Sheet 152. |
The old hill fort forms a prominent small hill rising out of the lower
land around. |
The exposure is within a most tastefully laid out caravan and camp site
now occupying the top of Ebury Hill. By the entrance on the right is a
very rotten exposure of grey sandstone with quartz. Faces of this rock
can be seen across an old quarry pool but; as they fall straight into
the water and are part of the landscaping in the camp site; they are
inaccessible. Further west in a delightful wood along a campsite
footpath; the Darnford Conglomerate is exposed in a small disused
quarry. There is too much moss to examine the rock in detail and the
surfaces are weathered; but the coarseness of the conglomerate is very
apparent in places whereas in others the pebbles are quite small. The
pebbles range in size from a few millimetres to 25 mm but it is
difficult to see any orientation; dip or the pattern of distribution.
In the photo the conglomerate can just be seen passing into a sandstone
(already mentioned) from right to left. |
A
public footpath goes through the campsite but access to the conglomerate
site is not on it and permission needs to be sought from reception
office. |
LGS Yes. Designation because this is a good exposure of Darnford
Conglomerate in its context of sandstones and the exposure is at the
boundary between conglomerates and sandstones. The site is borderline
LGS because some enhancement is necessary to allow better examination
of detail. |
Sedimentology/Stratigraphy |
| 0848 |
SJ 275 252 |
Sweeney Fen |
Cutting (road/railway) |
Lower Carboniferous: Sandy Limestone. Sheet 137. |
In
a cutting through the rolling country SW of Oswestry. A glacially
modified landscape. |
Exposure is up to 30 m long and 5 m high. It is most clearly examined at
the S end of the cutting. Thick beds of red sandstone (1 m) are exposed
here showing cross-bedding in contrast to the true dip. Scattered small
pebbles occur parallel to the cross-bedding within the thicker strata
and also a 40 mm layer of larger; mostly quartz pebbles is seen parallel
to the true bedding. These pebbles are white and pink; avr. 30 mm long
being well-rounded and densely packed. The sandstone is soft; iron-rich
and with little cement. About 1.5 m above the base truncation of topset
beds can be seen. Joints are common and break up the face in places. Dip
is 15° NNE. |
Beside public right of way. Easier from southern end because some
awkward fencing at northern end of cutting. |
LGS Yes. Designation because this shows the contrast between
cross-stratification and true dip in sandstones which form a transition
between Limestones and the Millstone grit of the L. and U.
Carboniferous. Wedd speaks of the Sandy Limestone in the south of its
outcrop; where it approaches the Triassic rocks as being decalcified and
bright red. This description fitted the exposure at this site and it was
considered that this site provided a good example of this rock
formation. Hillier raises uncertainty regarding the age of these rocks
possibly being of the Cefn-yr-Fedw Sandstone and thus Namurian rather
than Dinantian. All adds to the interest of this site. |
Sedimentology/Stratigraphy |
| 0851 |
SJ 277 245 |
Dolgoch Quarry |
Quarry (disused) |
Lower Carboniferous Limestone; Sheet 137. |
Part of the hilly Carboniferous Limestone escarpment SW of Oswestry. |
A
very impressive quarry on a large scale. The limestone dips NE at about
12°. There are excellent clear faces up to 10 m high on two sides of the
quarry; bedding is well-defined and approx. 2.5 m from the top is a
recess of clay and shaly material. In the middle of the face is a
massive bed 2 m thick and below are layers showing signs of bioturbation
and quite high energy stirring up of sediment. In this layer are found
many fossils; as death assemblages; notably Giganto-productus and the
coral Lithostrotion junceum. At the foot of the face are several strata
more regularly bedded. The succession here is typical of a very shallow
tropical sea. Variation in texture and colour of the different beds of
limestone can be examined but most of the rock is light grey and
crystalline. Some calcite mineralisation is evident and often associated
with slickensiding and faulting. A fine example of faulting is seen on
the west face; showing a displacement of about a metre. Other striking
features are the load casts; two particularly fine spherical structures
at the top of the quarry on the north face. There is a short tunnel
linking the main quarry with another and the roof of this is remarkable
for its projecting Giganto-productus and coral specimens all over the
surface. Detail of external ribbing is good and around the quarry a few
specimens of internal moulds of brachiopods illustrating well-preserved
muscle scars can be found. |
Via public right of way into this Shropshire Wildlife Trust site |
LGS Yes. Designation because the site is extensive; rich in fossils and
demonstrates vividly important rock-forming processes. Evidence of
faulting and of sedimentary structures and variation in lithology
reflecting environment of deposition all combine to make this a very
good LGS. |
Structure and Sedimentology/Stratigraphy |
| 0852 |
SJ 277 256 |
Sweeney Mountain (west
ridge) |
Quarry (disused) |
Upper Carboniferous: Millstone Grit: Cefn-y-Fedw Sandstone. Sheet 137. |
Quarry lies near the top of Sweeny Mountain. |
A
large; disused quarry with some good clear exposures of Cefn-yr-fedw
Sandstone. There is scope for more examination of the strata here. In
places the rock forms massive crags with little trace of stratification
but elsewhere; the bedding planes are clearly defined and a dip of up to
40° E can be measured. The rock is naturally cream in colour but often
stained orange; the iron compounds presumably derived from nearby
Triassic rocks. Texture is coarse and there are small scattered pebbles;
and thin quartz veins cut through the beds nearly vertical to the
bedding planes. There is a recessed shallow cave where a regular 250 mm
horizon of sandstone is surrounded by whitish; staining red; sandy
shale. |
On
private land adjacent to public footpath. |
LGS Yes. Designation because this is a good site exposing the deltaic
Millstone Grit of the Namurian. Educationally this could be used with a
group especially in contrast with a limestone quarry such as Dolgoch and
as part of a study of the succession of sedimentary strata south of
Oswestry. There is scope to discuss the iron-staining and to examine the
texture and general lithology in relation to environment of deposition. |
Sedimentology/Stratigraphy |
| 0855 |
SJ 537 136 |
Haughmond Hill;
Douglas's Leap |
Natural exposure |
Precambrian: Stretton Group: Burway Formation. Sheet 152 |
Cliffs at end of Haughmond Hill |
Around Douglas's Leap are vertical cliffs dropping into Queen Eleanor's
Bower. There are many and large exposures of green sandstones and flinty
shales; typical of the Stretton Group. Cliffs drop down into a valley
which seems to owe its existence to a fault line. It is not possible to
record all the exposures but from the 'Leap' views are magnificent and
the rocks easy to examine. Dips are always steep; near vertical and
within the thinly bedded shales are more massive sandstone beds;
micaceous and medium grained. There is a strong SW/NE direction of
strike. The main exposure is extensive and looks like a fault plane with
slickensides running parallel to the near vertical bedding. This may be
imaginative observation and would need to be confirmed or refuted. There
are interesting structures e.g. dimple-shaped ripple marks; parallel
grooves going down the dip; a branching structure on the surface. |
From footpath at top of hill |
LGS Yes. Designation because the site is a spectacular exposure of shales and sandstones of the Burway Formation; near to the boundary with
the Wentnor Group. Access is relatively easy. Also the association
with the fault and the interesting structures makes this possibly the
best site at the southern end of Haughmond Hill. |
Structure and Sedimentology/Stratigraphy |
| 0856 |
SJ 537 137 |
Queen Eleanor's
Bower |
Natural exposure |
Precambrian: Wentnor Series: Bayston and Oakwood Formation: Haughmond
Conglomerate. Sheet 152. |
This is on the SW corner of Haughmond Hill overlooking the Severn Valley
and more distant hills. |
There are several exposures of the Haughmond Conglomerate showing
pebbles up to 100 mm across. The conglomerate is polymict; poorly sorted
and the ratio of pebbles to matrix is high. Sometimes the exposure looks
like a concrete wall! Roundness varies from well-rounded to angular and
the matrix has a purple coloration. Pocock states that there are up to
80-90% igneous clasts; mostly rhyolite and felsite; the remaining 20%
being quartz and quartzite. |
Easy access from footpath at top of the hill. |
LGS Yes. Designation because this is one of three conglomerates within
the Bayston-Oakwood Formation and this is specifically linked to
Haughmond Hill; not being able to be traced with confidence south of
Bayston Hill. The exposures here are good and easy to study. It is
possible to use this exposure to put into context the rest of the rocks
present at the southern end of the hill as it lies unconformably upon
the Stretton Group within the Longmyndian in this locality. |
Sedimentology/Stratigraphy |
| 0857 |
SJ 537 138 |
Haughmond Hill
Fort |
Natural exposure |
Precambrian: Stretton Group: Burway Formation. Sheet 152. |
Old Hill Fort. Fine viewpoint at southern end of the hill overlooking
the Severn; Shrewsbury and the distant hills. |
There are several exposures of a fairly massively-bedded sandstone;
generally grey in colour with a purple tinge in places. Unfortunately
the rock surfaces are weathered and covered with algae etc. so detail
and structures are hard to distinguish without much hammering. Where the
bedding can be seen; the steep dip is evident to the SE. The views here
are magnificent and of great geological interest in relating landscape
features to the underlying rocks. |
From public footpath. |
LGS Yes. Designation because the site provides an excellent geomorphological perspective; a continuation of that at SJ 542133 with a
prospect of Nesscliffe and Hawkestone and more Welsh mountains. As
stated above; one can gain here a valuable understanding of the
relationship between rocks and relief. These scores are based on the
geomorphological value of the site. The rock exposures; although useful
in building up a picture of Haughmond Hill's geology; would only justify
LIGS. |
Geomorphology/Landscape |
| 0863 |
SJ 568 062 |
Eyton Rock |
Cliff |
Lower Permian: Bridgnorth Sandstone. Sheet 152 |
River cliff for 50 m along River Severn |
Up
to 12 m high red sandstone cliff; the rock showing uniform; well-sorted;
millet-seed texture in large cross-bedded units both planar and those
characteristic of dune structures. The dune bedding is lenticular in
form and up to 20 m across; thinning towards the planar sandstone at the
top. At the right-hand corner is a fault at a 70° angle of inclination;
steepening to 80° at the bottom where small displacement can be seen.
The fault plane is infilled. |
On
private land along river bank from the farm at Eyton-on-Severn. |
LGS Yes. Designation because Eyton Rock is an excellent substantial
river cliff exposure of the Bridgnorth Sandstone displaying both dune
and planar bedding (with a clear example of an infilled fault) sitting
close to the edge of the Church Stretton fault. |
Structure and Sedimentology/Stratigraphy |
| 0864 |
SJ 572 058 |
Eyton-on-Severn |
Cliff |
Triassic: Kidderminster Conglomerate resting unconformably upon Lower
Permian: Bridgnorth Sandstone. Sheet 152 |
River cliff above lowest terrace of the Severn. |
A
substantial cave now used for storage hollowed out of the typical red
uniform millet-seed grained Bridgnorth Sandstone. Overlying this
unconformably is a good exposure of Kidderminster Conglomerate. The
junction is abrupt. Below; the cross-bedded units in the sandstone are
less clear than those seen at Eyton Rock and become non-existent nearer
the junction where the bedding is flaggy and much thinner. Above the
boundary; the rock displays no bedding but consists of massive sandstone
with scattered pebbles; some of which show alignment and rough cross
stratification. There are patches of more densely packed pebbles of
variable size; mostly well-rounded. This conglomerate can be traced for
70 m or so towards the race course. These exposures are part of a small
faulted outlier of Kidderminster Conglomerate dipping south-east at 10°
located just SW of Eyton. It is interesting to compare the
characteristics of conglomerate here with that at the Hermitage;
Bridgnorth where the density of pebbles is much greater |
On
private land near farm at Eyton-on Severn |
LGS Yes. Designation because this site displays both Bridgnorth
Sandstone and Kidderminster Conglomerate in unconformable contact. The
pebbles in the conglomerate are well dispersed quite unlike the
exposures at The Hermitage. Also the exposure forms part of a small
faulted outlier and is the only such site in the area. |
Sedimentology/Stratigraphy |
| 0867 |
SJ 588 071 |
Brom Hill - Charlton Hill |
Natural exposure |
Precambrian: Uriconian volcanics; tuffs and andesite. |
Stands up as a grassy hillock surrounded by cultivated land thus
presenting a distinct boundary as well as a demonstration of the
connection between geology and relief. |
A
faulted inlier with scattered exposures of what is essentially a tuff -
fine to medium grained and flinty; indeed breaking sharply with sparks
when hammered. A grey-green ground mass contains pink crystals similar
to the rock on part of Charlton Hill summit. Some of the rock is more
feldspar-rich; therefore pinker; irregular and sharply jointed.
Textures vary; some being very fine and andesitic of a purple-green
colour. An apparent lineation of joints may suggest a shear zone. |
On
private land used for grazing and machinery storage close to a public
path. |
LGS Yes. Designation because the hill is an excellent illustration of
the link between geology and relief as well as being an accessible and
clear exposure of Uriconian Volcanics in a famous fault zone. This site
also links in well with the other exposures on and round the hill and so
adds to the understanding of the complex geology associated with the
fault zone. |
Mineralogy/Petrology |
| 0868 |
SJ 588 074 |
Charlton Hill
Farm |
Track/roadside |
Lower Cambrian: Wrekin Quartzite. Sheet 152 |
On
side of hill descending from small plateau of Uriconian Volcanics
forming Charlton Hill top. |
The exposure extends for more than 70 m parallel to the road. Bedding
planes are revealed clearly dipping 45° SSW. Ripple marks and many
oblique joints are visible. The rock is a well-sorted quartzite; grey
when fresh but here looking orange. The surface is algae-covered so
detail is not clear. The rock shows possible effects of being
metamorphosed as the quartz grains are fused together. |
Beside the public road. |
LGS Yes. Designation because although there are more impressive
exposures of this Cambrian Quartzite in the Wrekin area to the NE this
site is part of the faulted inlier and is needed to gain a more complete
picture of the range of rocks on Charlton Hill and to understand its
complex geology. |
Mineralogy/Petrology |
| 0869 |
SJ 588 076 |
Charlton Hill
Summit |
Natural exposure |
Precambrian: Felsite Dyke crossing conglomerate band. Sheet 152 |
The dyke is exposed at the summit of the prominent hill which lies
towards the northern end of the Church Stretton fault zone. |
Charlton Hill has extremely varied and complex geology because it lies
along the Church Stretton fault zone and the nature of the rocks; mainly
Uriconian Volcanics; show a range of textures and composition. The
summit of the hill is marked by a N-striking conspicuous wall of salmon
pink; splintery ;fine textured rock. This is one of several felsite
dykes found in the area penetrating the bedded series of lavas and
tuffs. The summit dyke is 1-2 m high and about 10 m wide. It is crossed
by many joints; including a set of noticeable parallel E-W trending
ones. A trig. point stands on the dyke. According to Pocock; but not
visible with the naked eye; the rock has some phenocrysts of
albite-oligoclase in a fine groundmass of albite-oligoclase and quartz. |
On
private land in pasture. |
LGS Yes. Designation because this is an unusually good exposure of felsite dykes crossing a band of Uriconian conglomerate. The summit
features can be seen in the context of varied surrounding volcanic rocks
as described in report SJ 588075. |
Mineralogy/Petrology |
| 0870 |
SJ 589 038 |
Cressage Plocks
Brook |
Crag |
Ordovician: Tremadoc Series: Sheinton Shales. Map 152 |
Striking downcutting in bed of brook to form a gorge; possibly
influenced by presence of a dam for the paper mill. |
Extensive exposures are visible both in the brook bed and up the sides
of this miniature gorge; 70 m long by up to 6 m high; whilst only 2 m
wide in places. These Sheinton Shales are olive-coloured and
argillaceous; ranging in thickness from almost paper shales to several
centimetres. Generally they split well and evenly though sometimes along
irregular joints. A gentle dip of up to 18° S is evident on both sides
of the gorge and in the brook bed itself. There are some harder bands;
found most obviously forming rapids; and these tend to break less
evenly. Further; there are a number of large concretions (stinkstones)
found predominantly at one horizon several metres up the gorge sides;
these can be examined from the large examples fallen into the brook - up
to 0.7 m X 0.5 m - where cone-in-cone structure can be seen clearly and
where the sulphurous stink can be experienced when these dense; hard
nodules are fractured. No fossils were detected. |
May be approached with permission from down or upstream. Not suitable
for more than two or three persons at a time. |
LGS Yes. Designation because not only is the site a remarkable example
of a small gorge but it also exhibits very extensive and easily examined
exposures of Sheinton Shales rising to a considerable height and varying
considerably in thickness and hardness. Especial importance must be
attached to the fine specimens of stinkstone; including those visible in
situ high up the gorge face in the same horizon. |
Structure and Sedimentology/Stratigraphy |
| 0872 |
SJ 589 075 |
Charlton Hill
(below Summit) |
Quarry (disused) |
Precambrian: Uriconian Volcanics; unclassified. Sheet 152. |
Forms the feature known as Charlton Hill; which is a faulted inlier. |
The grassy hill top has many rocky exposures; too numerous to describe
separately; but three rock types can be referred to here. Running nearly
parallel to the band of conglomerate and about 5 m away from it on the
east of the summit is an exposure of very black; hard; splintery rock;
this is clearly a basic lava and is extremely fine-textured. A few
metres south is the back wall of an old quarry with a pool at its base.
The igneous rock here is dark and in part vesicular; similar but less
densely black than the basalt just described. This may be andesitic in
composition. Striations are present trending roughly N-S; being
evidence of the many faults in the area and perhaps the reason for the
shattered appearance of the rock in this quarry. Towards the SW end of
the quarry; the texture becomes a little coarser; more typical of a fine
dolerite and there is a greener coloration. This dark igneous rock is
exposed generally between the quarry and the felsite dyke. West of the
dyke there is a significant change to medium-textured tuffs; grey with
pink; presumably feldspar crystals |
Via summit field farmed by Mr Davies. |
LGS Yes. Charlton Hill is a most important geological site for Uriconian and Cambrian rocks. There is such a fine range of lavas and
tuffs; can be studied along with the summit felsites and conglomerate
band; there is the Wrekin Quartzite at its foot; and there is the
western andesite quarry. |
Mineralogy/Petrology |
| 0873 |
SJ 592 064 |
Eaton
Constantine |
Quarry (disused) |
Upper Carboniferous: Upper Westphalian: Coed yr Allt Beds. Sheet 152 |
On
slope down to R. Severn in field. |
The exposure is 4-5 m high and vertical; revealing a fine sand/siltstone
which is cream; weathering brown in places. The map indicates an Upper
Carboniferous age and these rocks seem to be part of the Coed-yr Allt
Beds. The top half of the face shows very fine bedding with a gentle dip
of 12° E. There is some differential erosion and evidence of
cross-bedding; even channelling. The texture of the accessible
sand-brown; laminated fragments is medium-fine. The bottom half of the
face displays clearer cross-bedding and more massive structure with
angular; cream-coloured; randomly distributed clasts up to 10 mm across
visible from several metres away. The fragments effervesce with dilute
HCl thus confirming their calcareous nature. In the adjacent field were
many fragments of this breccia turned up by the plough. This breccia is
likely to be derived from the Spirorbis Limestone. There are many
diagonal and near vertical joints present on the face of the exposure;
which unfortunately cannot be studied closely because of a deep pool in
front. |
Via a public track from Eaton Constantine Village Hall but on private
land. There is a stagnant pond in front of the clear face which makes
close access difficult.. |
LGS Yes. Designation because this is an unusual exposure in the area of
siltstone and calcareous breccia from the Coed-yr-Allt Beds. There are
no other such exposures in the locality. The strata demonstrate
cross-bedded structures indicative of fluviatile deltaic environment
with some evidence of channelling. Broken limestone fragments have
accumulated to form the distinctive breccia related to the Spirorbis
Limestone. |
Sedimentology/Stratigraphy |
| 0875 |
SJ 607 037 |
Sheinton Brook |
Bank |
Ordovician: Tremadoc Series: Sheinton Shales. Sheet 152 |
The brook cuts into the steeply banked Sheinton Shales at the western
side of a now till- and alluvium-filled valley; revealing also extensive
brook-bed strata. |
This is the classic section in the Shumardia pusilla zone. Up to 7 m in
height of fairly uniform shale is present on the outside bend of a
meander. Grey; weathering olive; the shale is thinly-bedded (up to 10
mm); soft and easily broken and split. Considerable variation in dip;
from less than 20-40° SE; together with clear evidence of arching and
slumping. The flat shale beds dip into the brook and are visible 1 m
below the surface and towards the centre of the brook. Part of an
unidentified trilobite was seen and a few small brachiopods but the
abundance of fossils described by Pocock and others would need a more
careful search before they showed themselves to be there. When the water
level is very low the Kenley Grit can be seen as conglomerate blocks on
the bed of the brook; mostly in situ. |
From fields to west of brook with permission. |
LGS Yes. Designation because of the size accessibility and clarity of
the exposure of beds which are seldom seen so well. The fine sequence of
strata represents a range of L. Ordovician and Silurian formations along
the Sheinton Brook. The Kenley Grit lies unconformably upon the Sheinton
Shales and marks the start of the Llandoverian marine transgression. The
SSSI report describes this site as providing the best exposure of
Sheinton Shales of the Tremadoc Series in the area in which the series
was originally defined. Although not obviously so to the naked eye the
fossil faunas are rich and contain trilobites ostracods cystoids
hyolithids brachiopods sponges graptolites and an annelid. Many fossil
species were first defined from material collected here and the
trilobites from this locality have been the subject of particularly
detailed study in connection with their value as zone fossils. |
Fossils and Sedimentology/Stratigraphy |
| 0877 |
SJ 608 041 |
Sheinton Brook |
Bank |
Ordovician: Tremadoc Series: Sheinton Shales. Sheet 152 |
On
the Sheinton Brook just above the flood plain of the Severn. |
20
m downstream of the bridge at water level and just below is an obvious
exposure of 4-5 m in length of thinly-bedded olive-weathering shales
with the bedding planes clearly exposed at the foot of the bank
immediately underlying some till. A continuation of the beds is visible
underwater downstream and there are further exposures down the brook.
Dip is 20° SE. No fossils were observed. |
Via a gate east of the bridge; permission having been obtained. |
LGS Yes. The site is significant as one in a series of observable
exposures of different horizons and different beds; series and periods
stretching up the Sheinton Brook. There are better exposures of Sheinton
Shale. |
Sedimentology/Stratigraphy |
| 0878 |
SJ 610 032 |
Sheinton Brook |
Bank |
Silurian: Llandovery Series: Pentamerus Beds. Sheet 152 |
Brook is deeply incised here and exposure forms steep bank. |
The Llandovery Pentamerus Beds are exposed right across the bed of the
brook as well as extensively along the western bank up to a height of 3
m. This is a very good exposure displaying the shelly facies most
effectively. A prominent bed 400 mm thick of shelly limestone dips at
about 10° SE. Above this and below it are thinner limestone beds crammed
with brachiopods and separated by shaly limestone with soft shale
partings. Above these beds is a distinctive ginger-coloured shale which
is sandy and micaceous. Harder non-fossiliferous sandstone bands project
from the shales. Changes of dip (e.g. to 20° WSW !) appear to be the
result of slumping and some slump-induced folding is visible. The
brachiopods consist of the typical Pentamerus oblongus along with
Stricklandia lens and Atrypa reticularis. A coral was found (probably
Streptelasma whittardi). An exposure 3-4 m high of thinly bedded
strongly jointed fossiliferous brown weathering siltstones appears to
represent the upper horizons of the Pentamerus Beds. At water level is a
resistant band of blue-grey limestone. Above is fine-grained shale with
tiny brachiopods and slightly nodular calcareous siltstones. Although
the 4 m face is of uniform appearance there are within it nodules which
vary in size from 120 mm across to only 10 mm. This is a good site
especially if looked at in association with the site at SJ 608034. |
Access from woods and fields is difficult as there are no public
footpaths. It is probably best to approach by wading along the brook
upstream. |
LGS Yes. Designation because this is a crucial link in the chain of
varying exposures along the Sheinton Brook and is in itself a rare and
fine example of a substantial and clear exposure of Pentamerus Beds;
considered classic by Pocock. |
Fossils and Sedimentology/Stratigraphy |
| 0880 |
SJ 614 028 |
Sheinton Brook |
Bank |
Silurian: Upper Llandovery Series: Hughley Shales. Sheet SJ 60 -
Telford. |
The exposure represents the western limit to the meandering brook. |
The exposure is up to 3 m high and about 20 m long and consists of
moderately dipping (18° SE) thin; greyish shales interbedded with 60 mm
to 170 mm limier slabs; some of which fade out. Towards the base of the
exposure is one horizon of limestone slab with consistent regular
ripple-marking as well as numerous burrowing tracks and varied
sedimentary structures without any directional trend. These are
excellent examples of a bioturbated surface; usually associated with a
shallow sea and intermittently emergent sea floor. This seems to
contradict the accepted environment of a deepening sea to explain the
argillaceous sediments deposited at the time and giving rise to the
Hughley Shales. No mention of the trace fossils and the features
described has been found in the available literature. High up on the
bank are some more nodular blocks of fossil-packed limestone within the
thinly bedded shales; the latter break readily into small cuboid blocks
along joints. Fossils are found apparently in all horizons; including a
whole 180 mm Favosites towards the top; a 70 mm Halysites near the base
in the shales; small brachiopods in the shales and an 80 mm Heliolites
just above water level. The presence of these colonial corals in muddy
sediments was surprising. |
Downstream along path beside brook from Sheinwood on private land. |
LGS Yes. Designation because not only is the site a clear and easily
accessible (floods permitting) example of the Hughley Shales in this
area but it also represents one more link in the fine series of
successive strata demonstrated in the one brook. There are abundant
fossils as well as a beautiful ripple-marked horizon which furthermore
displays an unusually rich concentration of fossil burrows and trails.
The site offers scope for discussion about the possible environment of
deposition. |
Fossils and Sedimentology/Stratigraphy |
| 0882 |
SJ 625 013 |
Gleedon Hill - Much Wenlock |
Quarry (disused) |
Silurian: Wenlock Series: Much Wenlock Limestone |
Within the woods on the north of Wenlock Edge. |
This site shows a ballstone at ground level with clay pockets and
bedded; flaggy limestone dipping off the reef in a direction of 60°.
Fossils in sit' are clear to see; particularly corals e.g. Heliolites
interstinctus. Other fossils include crinoids; rhynchonellids and other
brachiopods. There is much replacement of original shell material by
pink calcite. To the left in a corner is a fault with much clay infill.
Left of the fault is crystalline; stratified limestone packed with
highly fragmented crinoids which becomes more nodular. Mudstone layers
are clearly visible and the nodules; both large and small are densely
packed and look like a stone wall with clay as 'mortar'. The dip seems
to be at an angle of about 10° in a northerly direction. |
Take a footpath on the left; a few metres along the Sheinton Road from
the junction with the A4169. Go left into the wood at a store place
where there is often litter. After about 300 m the path bears left
where an exposure is seen on the right. This is not the exposure
described here but 10 m on the site can be seen through the trees on the
left. Access in summer is difficult because of the vegetation. |
LGS Yes. LGS status on account of the variety of features typical of Wenlock Reef Facies and its related strata. The fault is of interest as
is the range of fossil material present. |
Fossils and Sedimentology/Stratigraphy |
| 0883 |
SJ 626 009 |
Shadwell Quarry - Much
Wenlock |
Quarry (disused) |
Silurian: Wenlock Series: Much Wenlock Limestone. Special Sheet 60 -
Telford. |
Once a hill; now a deep pit below Windmill Hill. |
The sight of the deep blue pool surrounded by grey; terraced faces from
the rim is a spectacular one. At the top there is grey shale on the RHS
and on the left is mostly Reef Limestone; these forming the top terrace
and rim of the quarry. Below is thinly bedded grey limestone and shale;
which rests on whiter; more crystalline limestone. This; in turn; lies
on more shaly beds. Fossils abound; especially brachiopods e.g. Atrypa
reticularis; Leptaena depressa; Meristina obtusa; some large and
well-preserved. Calcite; both white and pink; and with dog-tooth
crystals is common. Because of steepness of faces it is not easy to
examine all the strata closely. Near the entrance the slope down to the
first level seems to be of olive mudstone possibly an exposure of Lower
Ludlow shales |
Unofficially it is easy to get in to the quarry at the moment and
permission can be obtained from Lafarge-Redland. While the restoration
work is going on there is no problem but the situation is due to change.
See Ownership. |
LGS Yes. LGS on account of (1) its fossils; (2) the contrasting
limestone /shale horizons; (3) typical ballstone structures; albeit
disturbed by quarrying. |
Fossils and Sedimentology/Stratigraphy |
| 0884 |
SJ 628 016 |
Farley Quarry - Gleedon |
Quarry (working) |
Silurian: Wenlock Series: Wenlock Limestone and Reef. Special Sheet 60 -
Telford |
All exposures in a working quarry on the north end of Wenlock Edge. |
The face at the Gleedon end of the quarry to the left of the offices is
the most impressive of the many interesting exposures in this quarry.
Since the present company has cleaned up the faces it is possible to
examine close up (although there are dangerous over-hangs and a good
deal of instability) a striking ballstone embedded in stratified
limestone dipping approx. west at this point. Left of the ballstone;
there is some variation of dip and a series of faults and joints. Near
the left-hand corner a thin clay horizon is clearly displaced and the
faulting seems to have confused the dip of the strata. In the middle of
Farley Quarry there is an impressive section through the bedded
limestones where the changes in colour and texture can be appreciated.
One is at the level of grey fine mudstones inter-bedded with crystalline
slabs and nodules. It would appear that at this level the rocks have
become transitional between the Coalbrookdale Formation and the Wenlock
Limestone. It is the lowest part of the quarry at this time although
plans are to dig deeper thus a more complete vertical section may be
exposed in the near future. In the grey soft shales Atrypa reticularis
is abundant and an excellent Leptaena depressa was seen. At the Far End
Right there is a high vertical face of bedded limestone which is rubbly
on the top and becomes massive with tufa in joints lower down. To the
left of this is a broken up ballstone with reef scree material at its
foot. Here there are many typical Wenlock reef fossils especially large
corals e.g. Favosites gothlandicus; and stromotoporoids. On the right of
the far back wall is very irregularly bedded crinoidal limestone which
is rubbly and not necessarily the same as that which forms the top of
the back face. Once again there are many varied fossils to be picked up
freely. Opposite the weigh-bridge is a clean face of thinly bedded
limestone with a distinctive small anticline. On the RHS past the
offices the quarry face is vertical with thin regularly bedded limestone
some clay layers and nodules. A ballstone can be seen with prominent
joints; nodular limestone above and bedded below. Large nodules are
embedded in a clay matrix and look like a stone wall. Pink calcite is
common. At this site fossils were less abundant than in other parts of
the quarry. The variety of Silurian fossils to be found at Farley is
outstanding. |
Report to the offices after requesting permission beforehand. There are
dangerous over-hangs and a good deal of instability |
LGS Yes. The variety of Silurian fossils to be found at Farley is
outstanding. The rock exposures in the quarry are excellent and several
are worthy of LGS. The southern part of the quarry shows the strata
disturbed by faulting and is very instructive for any visiting groups
who also may appreciate the relationship between Wenlock Reef Facies and
the tabular limestone. |
Fossils and Sedimentology/Stratigraphy |
| 0889 |
SJ 636 024 |
Farley Dingle |
Stream/brook |
Silurian: Wenlock Series: Tickwood Beds. Special Sheet 60 - Telford |
A
deeply cut valley of the Farley Brook and tributaries. Waterfalls flow
over the various strata of the Tickwood Beds (FarleyMember) reflecting
the resistant and less resistant beds. |
This is a lovely place where the variations in the sedimentary strata
transitional between the Coalbrookdale Formation and the Much Wenlock
Formation can be studied. There is evidence here that the geomorphology
of the waterfalls and the deeply cut valley has been affected by
faulting which may have changed the course of the brook at this point.
The rocks are dipping at about 5° in a direction of 115° SE. At the
bottom of the waterfalls there is alternating olive shale and nodular;
harder limestone which accounts for their presence. These rocks are
similar to those at Farley Mill. Higher up the main waterfall; as the
water flows out of a tunnel; the shale is much greyer; perhaps
reflecting a change from Coalbrookdale Formation to the Farley Member.
These transitional beds are very variable and boundaries hard to define.
The height of the exposed rock in the waterfalls is about 9 m. Along
the small tributary which flows from just west of Woodhouse Farm are
many attractive tuffaceous deposits on both rocks and vegetation. |
Land is private but access can be gained from the bridge over the Farley
Brook at the main A4169 |
LGS Yes. For both geological and geomorphological reasons this site is
designated as a LGS. The exposures demonstrate the subtle variation
within the Tickwood Beds and the underlying Coalbrookdale Formation and
represent the lower strata of the former; to be compared with the
exposure at the 'new' road cutting where the upper strata merge with the
Much Wenlock Formation. Justification for a geomorphological designation
can be seen from the description above. |
Geomorphology/Landscape |
| 0891 |
SJ 659 065 |
Lydebrook
Dingle (N) |
Mine/adit |
Lower Carboniferous: Lower Limestone Formation below Little Wenlock
Basalt. Special Sheet 60 - Telford |
Forms part of valleyside of narrow wooded dingle. |
An
adit has been constructed approx. at the boundary between the limestone
and overlying basalt; possibly as a drainage tunnel for the old opencast
workings on the 'plateau' above. The basalt is very weathered but shows
its vesicular and amygdaloidal structures; and its typically black
colour and fine texture. It forms a near-vertical side to the valley and
3 m are visible. There are also numerous small; criss-crossing veins of
calcite within it. Next to the adit entrance the mineralisation becomes
vertical picking out a small fault or prominent joint. The contact with
the Lower Limestone is sharp and the boundary can be followed easily for
3 m or so. The limestone is hard; fine textured and clearly altered by
contact with the lava flow About 1 m is exposed at ground level;
consisting of a single bed. |
Very difficult. Permission needed from SGCT and access is up the stream
bed or along the steep sides of the Dingle through what must be almost
impenetrable vegetation in summer. Access to Dingle is down by the side
of the bridge on the Ironbridge by-pass. |
LGS Yes. Although difficult of access; this site is a 'must' for LGS.
The contact between the Little Wenlock Basalt and the Lower
Carboniferous Limestone is very clear and provides one of very few such
examples. The nature of the overlying lava flow and its effect on the
limestone are clearly displayed at this site. |
Mineralogy/Petrology |
| 0892 |
SJ 6615 0580 |
Lydebrook
Dingle (S) |
Quarry (disused) |
Lower Carboniferous: Lydebrook Sandstone. Special Sheet 60 - Telford |
On
the side of a wooded valley above the Dingle. |
An
excellent site for examining the Lydebrook Sandstone just off the public
footpath with easy access. The quarry is approx. 20 m across and the
faces rise to a max. height of 5 m. The colour of the rock is striking;
being creamy brown; weathering orange. The sandstone shows
cross-bedding and possible channelling. It is mainly coarse and is
sometimes well-sorted but in other places is conglomeratic; the pebbles
showing stratification. Thickness of beds is variable and the dip
direction and angle changes within the quarry; because of the
cross-bedding. The site displays good fresh rock exposures. |
Easy. Use the public footpath; the Shropshire Way; towards Leasows Farm.
Quarry is easily seen and reached shortly after the path bears left out
of Loamhole Dingle. |
LGS Yes. An excellent; easily accessible old quarry; suitable for a
group of students and one which allows close examination of the
characteristics of the basal member of the L. Carboniferous as it
reflects a shallow transgressing sea. Particularly good when looked at
along with the basal conglomerate at site SJ662058. |
Sedimentology/Stratigraphy |
| 0893 |
SJ 6615 0335 |
Benthall Edge
Cottage |
Quarry (disused) |
Silurian: Wenlock Series: Benthall Beds. Special Sheet 60 - Telford |
Quarry is cut into the top of Benthall Edge and is north-facing. |
Quite impressive exposures here extending along the crest for about 100
m. There is a variety of massive to flaggy fossiliferous; mainly
crystalline limestones inter-bedded with shales and siltstones. The
standard section for the Benthall Beds is at a nearby site on Benthall
Edge but there is much to be seen here. There are a series of old
quarries following the line of the crest. At the most westerly end of
this site; near a footpath which goes to Benthall Hall; the lower beds
are 0.25-0.3 m thick and nodular on the underside. Above 2 m the
limestone becomes nodular; the strata much thinner and they alternate
with green/brown mudstone. The latter is weathering to clay and tends to
wash down and cover the surface of the rock. Height of face is 9-12
metres. The top beds project in a more resistant layer of flaggy
limestone. About 10 m east is a vertical 'blasted' face where
ballstones can be seen surrounded by nodules embedded in mudstones and
shales. The rock has plentiful corals and brachiopods typical of the
Wenlock Limestone. At the east end; nodular strata dips at about 24° to
the SSE. The nodules result in undulating partings between beds. |
Easy via public footpath from Ironbridge or Benthall Hall. |
LGS Yes. The whole of Benthall Edge is worthy of designation as LGS
but there are several separate sites worthy of this status in their own
right. This is one such which offers ease of access and allows the
variations in the Benhall Beds to be studied. The massive flaggy nodular
and shaly/ muddy layers and also some reef structures provide evidence
of changing environments during the period of deposition. |
Sedimentology/Stratigraphy |
| 0894 |
SJ 662 057 |
Lydebrook
Dingle |
Natural exposure |
Lower Carboniferous: Lydebrook Sandstone. Special Sheet 60 - Telford |
On
the valley side of a deep wooded narrow dingle. |
An
exposure of the conglomeratic phase of the Lydebrook Sandstone. Main
exposure is 10 m long and 2.5 m high. It forms a massive face of coarse
conglomerate with 0.3 m of weathered sandstone at its base. Pebbles are
mainly quartz or quartzite; densely packed; and very varied in size;
ranging from 50 mm down to a few mm. Shape is sub-rounded to sub-angular
and the are set in a sandy matrix. On the right of the face the pebbles
show evidence of layering and possible cross-bedding. These layers seem
to dip approx. north. The pebble horizon gives way to sandstone higher
up the face; the boundary being very sharp. |
After the Ropewalk; follow footpath as it bears left uphill. Turn sharp
right at the yellow footpath sign and site is 30 m over a bank. No
problem about access. |
LGS Yes. An impressive conglomerate exposure in the Lydebrook
Sandstone; one to which one could take small groups without fear of
damage; can examine face close-up. Illustrates deposition in a shallow
marine sandbank-type environment. |
Sedimentology/Stratigraphy |
| 0895 |
SJ 662 058 |
Lydebrook
Dingle |
Natural exposure |
Lower Carboniferous: Lydebrook Sandstone. |
On
the side of a steep narrow valley above the stream. |
Stoney Hill fault crosses the dingle from SW to NE causing greater
amount of Lydebrook Sandstone to outcrop at this locality. It can be
seen forming massive rocky sides (20 m high) to the valley from this
point north and west. Some of the exposures are weathered and covered
with algae but there are a number of excellent ones. This is the
smallest of three possible LGS or LIGS sites. The sandstone is fresh;
cream/orange. The middle of the exposure shows evidence of channelling
as the base of the massive bed is distinctly concave and seems to rest a
thinner layer of softer; more clayey sediment and a pocket of lighter
sandstone with carbonaceous fragments. Above and below; the sandstone is
massive. |
As
the main footpath from the Ropewalk bears left; continue down towards
the stream along a less-used path. Before reaching the stream; the
exposure can be seen up the slope to the left. Access is not difficult. |
LGS Yes. Very useful when studied in association with other sites in
the Dingle. Shows the characteristics of a basal deposit laid down at
the beginning of a marine transgression; pebbles; coarse sand; and plant
fragments. |
Sedimentology/Stratigraphy |
| 0897 |
SJ 663 058 |
Lydebrook
Dingle (S) |
Stream/brook |
Silurian: Wenlock Shale: Coalbrookdale Formation. |
Exposure on the side of stream in deep; wooded; narrow valley. |
The Wenlock Shale can be seen overlain unconformably by the Lydebrook
Sandstone. The latter is distinctively yellow and conglomeratic
representing the basal L. Carboniferous marine transgression. The
exposure extends for about 10 m and is approx. 4 m high. 2 m of grey
shale is visible below the sandstone; the contact being clear to see.
The softer shale is recessed and an uneven boundary can be examined just
above ground level. |
Difficult. It is the policy of the Countryside Trust to discourage
disturbance of wildlife in this 'wilderness' environment (a gem amidst
all the development of Telford). Permission needed from Severn Gorge
Countryside Trust. |
LGS Yes. A most important site; seemingly not documented in the Telford
Memoir. Such a clear unconformity with visible contact between the
Silurian Wenlock series and the basal Carboniferous. |
Sedimentology/Stratigraphy |
| 0898 |
SJ 661 060 |
Lydebrook
Dingle (N) |
Stream/brook |
Lower Carboniferous: Lydebrook Sandstone. Special Sheet 60 - Telford |
Deeply cut narrow valley with waterfalls and rapids. |
Although this is a good site for looking at the Lydebrook Sandstone;
there are better exposures further downstream; allowing easier access.
This is described as a geomorphological site of great interest. The main
waterfall owes its existence to the relatively resistant sandstone and
the steep sides of the narrow dingle; and gives one the impression of
being in an upland valley in the hills rather than within the bounds of
Telford. The rocks are near horizontal and the waterfall has a vertical
drop of approx. 8m; the water eroding the bed of the stream to form
plunge pools below. There are other smaller falls; best described as
rapids; along the bed of the stream and much evidence of orange
iron-staining in the banks; probably derived from the old open-cast
workings nearby. It is at this point upstream that loose transported
blocks of basalt and limestone start to make their appearance. |
Difficult; no public access but permission may be obtained from the
Severn Gorge Countryside Trust. |
LGS Yes. As a geomorphological site of aesthetic and unusual interest
in the area; this site is recommended as LGS and should be considered
in the context of the whole of Lydebrook Dingle which is already an SSSI
on the grounds of its wildlife and botanical value. |
Geomorphology/Landscape |
| 0900 |
SJ 6635 0575 |
Loamhole Dingle - The Gorge |
Stream/brook |
Silurian: Wenlock Series: Wenlock Shale: Coalbrookdale Formation.
Special Sheet 60 - Telford |
Within a deeply cut dingle exposed on the high bank above the stream. |
Next to a water tunnel and waterfall is a vertical bank of Wenlock
Shale; 4.5 m high and extending at least 0.5 m under water. The 'shale '
is more of a mudstone here; uniform and breaking into small;
multi-sided; thin fragments. About 0.5 m above water level is a definite
recess; indicating a more clayey layer. In front of the face is a
deepish pool fed by water from the tunnel; this makes access to the face
rather difficult. About 9 m downstream; is a 10 m long bank of the same
rock. Dalmanites caudatus and orthocones are relatively common |
From Museum of Iron; along the Ropewalk and then via the stream bed. |
LGS Yes. The exposures of Wenlock Shale; (Coalbrookdale Formation) in
Loamhole Dingle are the best north of the Severn; according to the
Telford Memoir. This is a particularly clear and representative example
with abundant fossils; especially trilobites and cephalopods. |
Fossils and Sedimentology/Stratigraphy |
| 0901 |
SJ 664 034 |
Pattins Quarry - Benthall
Edge |
Quarry (disused) |
Silurian: Wenlock Series: Benthall Beds. Special Sheet 60 - Telford |
Quarry forms elongated 'valley' feature below the top of Benthall Edge. |
There are many features of interest in this quarry; which is taken as
the standard section for the Benthall Beds. These are massive to flaggy;
shelly; crystalline limestones with nodular horizons and shaly partings.
There is evidence of a ballstone with a pocket of nodular limestone
within it. Above this is more nodular limestone with projecting slabs of
resistant; crystalline material. Beds dip at an angle of about 25° and
in an approx. SE direction. At the SW end the face shows clear evidence
of faulting; there is displacement of 0.5 m to the left and softer
strata 'slump' towards the fault plane. Other small faults occur and
give rise to small scale step-faulting. Nodules cause undulations
between beds and a small monoclinal fold is seen. The quarry is an
excellent place for the collecting of fossils from the many rock
fragments lying around; the Benthall Beds containing many corals;
stromotoporoids and typical Wenlock brachiopods. |
|
LGS Yes. This quarry has within it the standard section for the Benthall Beds and that alone recommends the site as
LGS. However; there
are other features as well as the impressive section through these
varied limestones; particularly the examples of faulting and small-scale
folding and the range of fossils present in the quarry. |
Structure and Sedimentology/Stratigraphy |
| 0903 |
SJ 667 035 |
Bowers Brook - Benthall
Edge |
Stream/brook |
Silurian: Wenlock Series: Coalbrookdale Beds: Farley Member: and
Benthall Beds. Carboniferous; Upper Carboniferous: Coal Measures
Sandstone. Special Sheet 60 - Telford |
A
deeply cut stream with waterfalls incised in the north slope of the
Ironbridge Gorge in Benthall Woods |
The Broseley Fault crosses the brook at a point where it comes through a
pipe by the lower footpath to flow into the R. Severn. There is no
change in rock type though here. Behind the pipe are the top 3 m of the
Coalbrookdale beds; green; limy mudstones exposed in the stream bed and
banks. Dalmanites caudatus and orthocones are found in these shales. The
harder strata of the Farley Member form a waterfall and it is clear to
see the muddy shales becoming more limy and containing more nodules
towards the top of the waterfall. Access further up the valley is
dangerous and difficult but the Farley strata continue upstream for at
least 200 m before being succeeded by the very fossiliferous Benthall
beds; mostly flaggy limestones; which are exposed almost to the top of
the Edge where Coal Measure sandstone lies unconformably on the Silurian
strata. A series of small waterfalls and cliffs continue from the lowest
level to almost the top of the Edge. |
Quite difficult; even dangerous; because the brook is deeply cut and
precipitous; but limited access is possible from the paths at several
levels for those of reasonable fitness. |
LGS Yes. LGS because such a depth of exposed strata in such a
remarkable geomorphological context is rare in the area. The waterfalls;
the fault and the unconformity between the Coal Measure sandstone and
the Benthall beds combine with the exposure of the Farley Member and the
Coalbrookdale Formation to make this one of the most important sites in
the Ironbridge Gorge. |
Sedimentology/Stratigraphy |
| 0904 |
SJ 670 039 |
Lincoln Hill - Ironbridge |
Quarry (disused) |
Silurian: Wenlock Series: Benthall Beds. Special Sheet 60 - Telford |
Lincoln Hill stands imposingly at the western end of the Ironbridge
Gorge above the N bank of the R. Severn. The quarry and best exposures
lie on the steep east side of the hill. Below Lincoln Hill are deep
underground caverns in the limestone; the legacy of extensive mining in
the Gorge. |
Along the path from the top of Church Road to the Rotunda are several
exposures of the reef facies; easily examined and providing a good range
of shelly fauna. On the left are about 10 m of Benthall Beds half a
metre high. Next to this is a small quarry of grey; nodular limestone
with indistinct bedding up to 4 m high in the upper exposure and 2 m
high in the lower one. The rocks appear to be dipping SE at about 36°.
At the bottom of the exposure; the stratification is clearer; nodules
less distinct and there appears to be part of a ballstone. There are
many fossils; often very fragmented; but a good stromotoporoid was
observed and rhynchonellid brachiopods. Immediately parallel to the
Rotunda path is a depression (presumably a former small quarry) where
there are further exposures of clean nodular beds of limestone and here
many fossils can be found in the loose fragments on the ground. The most
useful fossil sites are on the steep east face above the old quarry. One
face of the old quarry is freshly exposed and thin irregular beds of
Wenlock Limestone are seen to be dipping ESE; towards the top of the
face layers become more regular. The rocks are cream/brown in colour;
typical of the Wenlock limestones. |
Via footpaths from various roads leading from Ironbridge up to Lincoln
hill. Although much of Lincoln Hill is open access; permission is needed
to visit the old quarry and the fossil sites on the east face. |
LGS Yes. Already an SSSI; Lincoln Hill is an historically famous fossil
locality. The abundant shelly fauna have been studied since the time of
Murchison; who first described the site.This is the type locality for a
number of fossil groups; notably ostracods; and in the last few years
has played a key role in fresh studies of the fossil fauna of the
Wenlock Series; detailed studies of the fauna of Lincoln Hill have been
important in understanding the environment of the reefs and the adjacent
backreef lagoon. |
Fossils and Sedimentology/Stratigraphy |
| 0905 |
SJ 672 039 |
Lincoln Hill - Ironbridge |
Natural exposure |
Upper Carboniferous: Lower Coal Measure Sandstone. |
Exposure is at the top of Lincoln Hill. |
There is a tongue of rock just off the Limeburner's path to the
Rotunda. At its base is what seems to be the opening to a tunnel. Here;
sandstone; weathering brown can be seen dipping at about 18° SE. The
sandstone is light in colour and fine-medium textured with little
evidence of cementation; the sand grains rubbing off on one's fingers.
The exposure is about 3 m high and rests unconformably upon the
Benthall Beds although at this site the contact is not visible. |
A
few metres on the right of the Limeburner's path to the Rotunda;
approaching from the top of Lincoln Hill road. |
LGS Yes. The site provides an easily accessible example of Coal Measure
Sandstone next to the Silurian Limestone exposures on Lincoln Hill. |
Sedimentology/Stratigraphy |
| 0906 |
SJ 6725 0405 |
Lincoln Hill - Ironbridge |
Quarry (disused) |
Upper Carboniferous: Lower Coal Measure Sandstone overlying Silurian:
Wenlock Series: Benthall Beds. Special Sheet 60 - Telford |
The exposure is on the NW-facing slope of an elongated former quarry on
the top of Lincoln Hill |
Light grey; weathering brown; 0.6-0.7 m thick massive sandstone is
dipping at approx. 20° SE. Texture is that of a medium sand and this
rock is underlain by 0.2 m of soft grey shale which weathers to clay.
The shale tapers out to the right and seems to form a pocket between the
sandstone and hard crystalline limestone beneath. This is a good example
of the unconformity between Wenlock Series and the L. Coal Measures. The
base of the sandstone is a thin pebbly layer; suggesting a basal
conglomerate. The limestone here becomes more nodular beneath the
massive horizon and is crinoidal. |
Fairly easily reached by turning sharp right off the Limeburner's path
along the bottom of the now naturalised old quarry and then looking up
the slope to the right. |
LGS Yes. Designation because this is a very good example of an
unconformity between Silurian Wenlock Series and the overlying Lower
Coal Measure Sandstone where the contact is clearly visible. |
Sedimentology/Stratigraphy |
| 0910 |
SJ 729 158 |
Lilleshall Hill |
Natural exposure |
Precambrian: Uriconian Volcanics. Special Sheet 60 - Telford |
Lilleshall Hill rises dramatically from the surrounding plain to a
height of 132 m AOD. The Uriconian crags are on the top. Forms smooth
dipping plane on NW side of the hill. |
These rocks are described in 'The Regional Geology of Central England'
as albite rhyolites with tuffs and breccias. The exposures are very
impressive with flinty fine-grained pink rhyolites showing rock cleavage
in an approx. E-W direction. This has the effect of producing parallel
slabby small faces exposed almost en echelon along the top of the hill;
trending in line with the Lilleshall Fault. On the east side of the hill
just below the monument there is a marked boundary between the cleaved
rhyolites and the irregular masses of coarse tuffs. Fragments of
flow-banded rhyolite 10 mm long are clearly seen in the tuffs. Examples
of a more coarsely crystalline tuff much deeper red in colour are also
present on and around the hill. On the NW side the rhyolites are
splintered and seem shattered presumably the result of faulting which is
also responsible for the cleavage lineation. A very striking steep
smooth slabby exposure of the Lilleshall Fault forms the edge of the
hill on the west. The abrupt change of slope at the foot of the hill
here corresponds to the faulted margin. It is possible to see multiple
parallel fault planes close at hand. The height of the fault plane is
approx. 15 m. |
From the road that goes round the hill; enter a wooded area over a wire
fence at the NW end. Others obviously go in here although it is not a
public footpath. |
LGS Yes. Not only on account of its geomorphological value but because
here are exposed the most northerly Uriconian rocks along the Church
Stretton Fault System. Also the varying textures of the volcanic rocks
can be easily be examined. An excellent example of a large fault plane
made more special as it is the northerly end of the Church Stretton
Fault System and when standing on the top of the hill; it can be lined
up with the Wrekin and the trend determined. |
Mineralogy/Petrology |
| 0911 |
SJ 734 165 |
Lilleshall (N) (limestone
quarries) |
Quarry (disused) |
Lower Carboniferous: Dinantian: Visean: Carboniferous Limestone. Sheet
153; Wolverhampton. |
Deep excavated chasms; once quarried now very overgrown. |
At
first sight no rock seems visible because the steep slopes are covered
with slipped soil and thick ivy and other vegetation; including many
fallen trees. A large specimen of Lithostrotion junceum was embedded in
the path and there was evidence of other limestone fragments scattered
around. There are large pools with obscured faces going steeply into the
water with no access. Below a lower path; however; formerly a quarry
track with lime kilns and tunnels; a good exposure of limestone was
present. It is possible to reach this exposure and near-horizontal;
irregularly bedded limestone rises to about 16 m forming the edge of
excavation. This seems to be the level down to which quarrying as
opposed to mining which also took place here; was carried out. There are
recesses in the face; some of which represent a red shale within the
limestone. The limestone is cream/pink in colour; fine textured; nodular
in appearance and dense. This is described in the Telford Memoir as
concretionary. |
Open access via footpaths in the woods at the North end of Lilleshall. |
LGS Yes. Part of the faulted Inlier at Lilleshall and the only
Carboniferous Limestone north of the Wrekin area in the east of the
county. It also completes the geological picture of the compact
Lilleshall Inlier itself. |
Sedimentology/Stratigraphy |
| 0912 |
SO 585 977 |
Knowle Quarry - Wenlock
Edge |
Quarry (disused) |
Silurian: Wenlock Series: Much Wenlock Limestone Formation. Sheet 152
or SO59. |
On
the dip slope of Wenlock Edge. |
The quarry illustrates very well the relationship between bioherm reef
and inter-bedded nodular and uniform Silurian limestones of the Wenlock
Series. There are thin beds of shale which weather more quickly and form
recesses. A good example of arching can be seen above the reef. The
south end of the quarry has uniform thin beds of stratified limestone
and shale. At the north end is a fault with a calcite vein.
Reef-building stromotoporoids and colonial corals (mostly tabulate) are
abundant and many other typical fossils are found e.g. crinoids
brachiopods inc. Leptaena depressa bryozoans Poleumita discors and
centrifugus and occasional trilobite fragments. Quarry is approx. 40 m
wide and height of exposures is up to 8 m. At the bottom of the steps
at the S end is a smaller exposure showing reef structures and
stratified limestone. Here it is possible to examine the face close up. |
This quarry is 4.5 km SW of Much Wenlock. Access from NT car park and
public footpath. It is necessary to keep to the paths here in order to
protect wild flowers. |
LGS Yes. An excellent example of patch reef and relationship with interbedded nodular and tabular limestones (Silurian). There are other
features such as fault and mineralisation. |
Fossils and Sedimentology/Stratigraphy |
| 0915 |
SO 463 924 |
Hazler Quarry - Hope
Bowdler |
Quarry (disused) |
Precambrian (Uriconian Volcanics); Ordovician (Caradoc Series: Harnage
Shales) |
On
the SW side of Hazler Hill |
The quarry is located in Uriconian basalt and tuffs which can be seen to
dip 50-80° N. The basalt is weathered showing blue-green mineralisation;
the dolerite is green. There is a Neptunean dyke in the right-hand
corner of the quarry - see Toghill and Greig. The 70 mm cleft has been
cleaned out since February 2000 but is increasingly deeply recessed with
a smooth surface filmed with water and algae so not readily identifiable
for what it is. The few fragments of brown weathered Harnage Shale
infill nearby were difficult to identify and showed no evidence of
fossils. This site although well-known and considered to be important is
now very disappointing. |
Beside public lane. |
LGS Yes. Designation because the presence of the Neptunean dyke within
the Ordovician/Precambrian unconformity is the only local example. |
Sedimentology/Stratigraphy |
| 0916 |
SO 464 902 |
Hatton Bridge |
Stream/brook |
Ordovician: Caradoc Series: Acton Scott Beds; sandstones and siltstones |
Forms a gorge through the sandstones. |
The Acton Scott Beds are extensively exposed along and above the brook
for a stretch of 40 m with a cliff rising to 7 m above the water and
descending to 1.5 m below. The rocks consist mainly of flat slabs
gently dipping; thinning higher up the face. The clearest exposures are
in the water either in the plunge pool by the bridge or in the brook bed
below the pool. The predominant rock is a fine-grained olive well-sorted
sandstone which forms a prominent ridge above the muds and shales about
water level. There are some grey shalier layers containing tiny fossils
and some hard yellow siltstones with many decalcified fossils. 20 m
downstream of the bridge are exposed calcareous fossiliferous blocks
though most fossils are decalcified; these include some excellent moulds
of brachiopods; Reuschella semiglobata; Onniella grandis; trilobites and
tentaculites were also seen. 100 m upstream of the bridge (on land owned
by the same farmer) can be seen a 3.5 m high bank of soft
thinly-laminated mudstone which breaks into small flat fragments and
weathers into brown soil; it contains occasional harder sandier layers.
Other exposures of a similar type can be found further up the brook
towards Hatton. |
On
private land over fence on public bridge |
LGS Yes. Designation because the site is unusually large and clear for
the Acton Scott Beds with a range of rock types and valuable highly fossiliferous material at different horizons. The plunge pool and the
river cliff with the several metres wide brook-bed exposures are
themselves significant geomorphological features in the context of the
Acton Scott Beds. |
Fossils and Sedimentology/Stratigraphy |
| 0917 |
SO 467 908 |
Chelmick below
Little Coppice |
Bank |
Ordovician: Caradoc Series: Cheney Longville Flags; sandstones and
siltstones. Sheet SO49. |
Brook runs down the dip slope of the strata towards Hatton. |
A
series of small rapids in the brook running down the bedding planes with
a dip which is 20-25° SE. Harder bands (the sandier layers) cause the
rapids to form; these alternate with shales to give a rapid and plunge
pool effect. The sandstone is finely laminated and splits along the
partings like a shale. It is soft ginger and micaceous and sometimes has
a nodular-like upper surface. A good example of ripple marks was seen.
The shaly layers tend to yield more fossils which include Dalmanella
wattsi; Sowerbyella; and Strophomena grandis as part of a typical
Marshbrookian fauna. |
Beside public right of way (as now diverted along field boundary) |
LGS Yes. Designation because of the clear exposure of a succession in
the Cheney Longville Beds of fossiliferous stronger and weaker sandstone
and shaly bands (the latter replaced by small plunge pools); the
excellent ginger sandstone itself appears in a range of strengths.
Beautiful parallel ripple-marks. Its combination with the sites at
Chelmick Farm and Chelmick Little Coppice provides a useful succession
of exposures within the Cheney Longville Beds. |
Fossils and Sedimentology/Stratigraphy |
| 0924 |
SO 509 979 |
Chatwall Sheep
Pens |
Quarry (disused) |
Ordovician: Caradoc Series: Hoar Edge Grit |
Just below the top of Hoar Edge. |
A
large quarry with faces 6 m high in thick irregularly bedded sandstone;
some beds 1.5 m thick. Many diagonal joints and joint planes can be
seen. The sandstone (or grit) is coarse and cream weathering brown with
quartz pebbles a few millimetres across. At the base of a thick stratum
are many small pebbles. This is a typical basal bed laid down during a
marine transgression; in this case at the beginning of Caradocian times.
The Hoar Edge Grit is finer and less conglomeratic than the Kenley Grit
deposited at the start of the Llandovery transgression. Many big blocks
3 m by 1.5 m lie on the floor of the quarry; many with holes where
pebbles have fallen out. The clasts tend to be mainly angular although
the Grit as a whole has been described by Hains as having rounded clasts.
The Grit has a dip of approx. 50° SE. |
In
private woodland 40 m from a public right of way |
LGS Yes. Designation because this is a substantial exposure of Hoar
Edge Grit typical of the sandy as distinct from the shelly facies. Hains
considers exposures are poor in this area so this is an important site.
Although in private woodland access is easy. |
Sedimentology/Stratigraphy |
| 0925 |
SO 513 973 |
Yell Bank - Chatwall |
Quarry (working) |
Ordovician: Caradoc Series: Chatwall Flags and Sandstone. Sheet SO59 |
Excavation in field just below top of Yell Bank. |
These are exciting new exposures presumably excavated by the farmer to
provide stone for his own use. The rock being quarried is flaggy and
highly fossiliferous sandstone which abruptly becomes a coarse
conglomerate. The descriptions of Chatwall Sandstone in the literature
speak of a basal conglomerate; this is strikingly it! The clasts are
rounded (often quartz or quartzite) but there is much variation e.g.
rhyolite and dolerite. The sandstone is a uniform well-sorted medium
rock; light brown in colour. Both rock types are superbly exposed at
the moment. Further west (parallel to the road) there is pure thinly
stratified fine to medium sandstone and (at the western extremity)
brown-grey flaggy sandstone is dipping 42° SE. Within it are lenses of
conglomerate; the rock clearly splits along bedding planes into thinnish
slabs. Above this horizon the conglomerate becomes more continuous. The
exposure has been excavated along bedding planes and at the top (just
below the road) is a 2 m layer of chaotic loose flags at all angles. The
fossils (mainly brachiopods) are not evenly distributed and are usually
decalcified. |
via field gate onto public road |
LGS Yes. Designation because it is a new fresh exposure of Chatwall
Flags and Sandstone with an unusually good basal conglomerate. It
demonstrates the lithology and the fauna of these rocks in a striking
way and is accessible (with permission) for group study. |
Sedimentology/Stratigraphy |
| 0926 |
SO 514 974 |
Chatwall Home
Farm |
Cutting (road/railway) |
Ordovician: Caradoc Series: Chatwall Sandstone and alternata Limestone.
Sheet SO59. |
The site is on top of Yell Bank (a prominent ridge) where a driveway to
Chatwall Home Farm cuts through a succession of Ordovician strata. |
A
sequence of steeply dipping (45-50° SE) sedimentary strata are exposed
here. The details of the rock succession are difficult to see because of
moss and algae and finding boundaries was challenging especially as the
domestic helper at the farm was distinctly edgy about our presence. The
length of the immediate cutting is approx. 23 m but exposures continue
nearer the house. The height is about 4 m. The boundary between Chatwall
Flags and Sandstone could not be identified with confidence (if it was
indeed there). The sandstone is fine textured brown and with beds of
varying thickness. Some evidence of small pebbles in the sandstone was
seen. On the RHS 6 m from the road is a prominent recessed layer which
on close examination reveals poorly preserved brachiopod shells. This
was taken to be the boundary between the Chatwall Sandstone and
alternata Limestone. The latter appeared sandy and flaggy but with
shelly lenses. By the roadside are several 'in situ' ground level
exposures of shelly alternata limestone. Dean has described in detail
the rocks present at this site and should be referred to. |
Beside private drive. Permission needed from owners. |
LGS Yes. Designation because Dean's study of the faunas from this
section showed that the 3 groups of beds could be assigned to Upper Longvillian Lower Longvillian and Soudleyan and that the highest and
lowest zones of the Lower Longvillian were absent. These faunal breaks
together with the changes in lithology at the top and base of the Lower
Longvillian Beds led Dean to conclude that non-sequences occur both
above and below the rocks of that stage. He also suggested the base of
the Chatwall Sandstone should be taken on lithological criteria at a
horizon some 24-27 m above that defined by Pocock. |
Sedimentology/Stratigraphy |
| 0930 |
SO 5420 9775 |
Church Preen
Quarry |
Quarry (disused) |
Silurian: Llandovery Series: Kenley Grit |
On
the hillside below Church Preen village; on part of Kenley Edge. |
A
fair-sized disused quarry in the Kenley Grit. The face is approx. 4 m
high. The bottom 2 m consists of thick beds of coarse pebbly sandstone
weathering orange-brown dipping SE at about 10°. Within these beds are
two recessed horizons of finer muddier material of thicknesses 20-30 mm
and 70 mm. These thinner layers are shaly and contain occasional small
pebbles. Each of the thick layers has conglomeratic horizons at
intervals. The face breaks up along vertical and oblique joints into
large blocks. Halfway up the face the beds are less massive and are
somewhat irregular. Smaller blocks are rounded where they have become
weathered and tend to be loose. There are occasional large slabs near
the top. At one place along the face glacial till appears to penetrate
to a depth of a metre vertically and fills pockets with varied sized
bits of Kenley Grit quartz and erratics. Within the till are small and
large pebbles and shelly shale in a silty matrix; all crumbly and soft.
There is evidence to suggest faulting has taken place. Some of the Grit
in the middle section of the face near a dead tree has a curved base and
this is underlain by a recess of softer mudstone. There is also evidence
of the gritstone beds wedging out to the right; cross-stratification and
a change in the dip of the strata. This may suggest rapidly changing
sediment deposition in a high energy shallow marine environment. |
Permission needed from New Holding Farm. Then easy access can be gained
through a field gate. |
LGS Yes. Designation because the quarry displays excellent exposures of
the Kenley Grit with interesting sedimentary structures and overlying
till. Such large exposures of this rock type are not often found. |
Sedimentology/Stratigraphy |
| 0932 |
SO 542 982 |
Church Preen
Manor |
Pond-bottom exposure |
Ordovician: Caradoc Series: Cheney Longville Flags; and Silurian:
Llandovery Series: Kenley Grit. Sheet SO 59. |
Pond is dug out in the gardens of Church Preen Manor on the dip slope of
the Kenley Ridge. |
A
remarkable site; visible only every 4 years or so when the owner drains
the Victorian pond lying in the course of the brook in order to clear
the rapidly accumulating silt. The beautifully polished alternata
Limestone in situ makes up part of the floor of the pond. The limestone
consists of shelly strata (seen to be often lenticular elsewhere) is
grey in colour and fine-textured. The name reflects the abundance of the
brachiopod Heterorthis alternata. Had it been possible to examine more
closely the fossil content of this exposure other brachiopods e.g.
Kjaerina bipartita and Sowerbyella sericea and such trilobites as
Broeggerolithus longiceps might have been present. At the bridge looking
up stream Kenley Grit is exposed on the right bank. Here it is quite
weathered but the quartz pebbles are distinctive. There is a gentle 10°
dip to the SE. Immediately under the bridge the Kenley Grit can be seen
overstepping the underlying Cheney Longville Flags marking the start of
the Silurian marine transgression. There is very little angular
difference at this unconformable boundary; both rock types dip SE at
between 10° and 20°. There is a marked contrast between the thick
orange-brown coarse pebbly Kenley Grit (reflecting a near-shore facies)
and the thin fine textured grey-green Cheney Longville Flags (reflecting
a low energy shelf environment in late Ordovician times). It was not
appropriate to disturb the stream bed in search of representative
fossils. |
Can be seen from the side of the pond when this has been drained and
cleared; closer viewing would be possible but this is hardly a site to
be placed on any itinerary! Permission must be obtained from Mr and Mrs
P. Trevor-Jones. |
LGS Yes. Designation because of the clarity of the unconformable
boundary where the Kenley Grit oversteps the Cheney Longville Flags. |
Fossils and Sedimentology/Stratigraphy |
| 0934 |
SO 552 944 |
Wilderhope
Youth Hostel Entrance (Lutwyche Hall) |
Cutting (road/railway) |
Silurian: Wenlock Series: Wenlock Limestone. Sheet 166 |
At
the crest of Wenlock Edge. |
A
60 metre length of limestone face exposed a few metres back from the
public road; up to 8 m in height but diminishing to the NE. The clearest
section is 15 m long at the SW end. Dips 12° SE. The rock is cream/grey
with flaggy finely crystalline projections but generally discretely
nodular with shale partings and consequent wavy partings between beds.
The occasional thick resistant layers have uneven undersides with shales
below. At the S end the shale is more substantial than further N; up to
50% of the face. There are two major near-vertical joints at the SW end
with shaly infilling; these may be faults but if so movement has been
slight. There are fragments of small brachiopods and evidence of
crinoids. |
Beside public road. |
LGS Yes. Designation because it lies in the transition zone between the
'reef tract' to the NE and the 'off reef tract' to the SW. It shows a
variety of limestone lithologies effectively including micrite
bioturbated wackestone and pelmatozoan debris. |
Sedimentology/Stratigraphy |
| 0935 |
SO 5620 9555 |
Easthope (NE) - Wenlock
Edge |
Cliff |
Silurian: Wenlock Series: Much Wenlock Formation (reef ). Sheet SO59. |
Just below B4371 on the scarp face of Wenlock Edge. |
Two adjacent exposures. The higher one consists of nodular reef facies
bedded with clay between the nodules. The limestone becomes more flaggy
at the top of the section just below the road. There is then a 5 m
barrier of vegetation and then a ballstone; rather overgrown; up to 0.9
m across; can be seen at a lower level within the Tickwood Beds. The
usual common Wenlock reef fauna is present. The Tickwood Beds (Coalbrookdale
Formation Farley Member) can be seen to the right of the ballstone.
These are nodular with regular 50-60 mm beds as well as clay partings.
No actual contact visible between the Much Wenlock Limestone Formation
and the Tickwood Beds. |
Easy access down a track from the B4371. It is a safe and easy site to
study. |
LGS Yes. This is already an SSSI on account of its being the most
southerly exposure of Wenlock Reef facies on Wenlock Edge. |
Sedimentology/Stratigraphy |
| 0936 |
SO 563 917 |
Shipton (Old Lane) |
Track/roadside |
Silurian: Downton Series: with 'Ludlow Bone Bed' at base; overlying
Ludlow Series: Whitcliffe Beds. |
Lane on the dip slope of the Aymestry Limestone towards Corvedale |
Here the basal bed of the Downton Castle Sandstone (2.4 m) is apparently
overlying the Ludlow Bone Bed which is said to occur (B.A. Hains) as two
impersistent beds (13 mm thick and 100 mm apart). Although the present
surveyor found possible evidence of this identification was
inconclusive. Buff silty shales of the Downton Castle Sandstone were
seen as were the succeeding yellow flaggy sandstones. The latter were
fine grained and micaceous with cross-bedding and fine laminations. But
as the lower beds of the Downtonian were silty (and therefore similar to
the upper Whitcliffe especially as the surfaces were strongly weathered)
the boundary was difficult to define. Nevertheless one metre above
ground level a recess may have been the position of the Bone Bed
particularly as below it the siltstones seemed more lime-rich and a
Fuchsella amygdalina was found in situ. |
Beside public lane |
LGS Yes. Designation because this is the only well-preserved and
accessible exposure of the transition from Upper Ludlow Shales to
Downton Castle Sandstone in this area Exposures of the Ludlow Bone Bed
are rare so this site (with its potential for showing the environmental
change across the Ludlow/Downton boundary) is of great value. |
Sedimentology/Stratigraphy |
| 0939 |
SO 569 965 |
Wenlock Edge -
Ippikin's Rock |
Cliff |
Silurian: Wenlock Series: Much Wenlock Formation; reef facies. Sheet
SO59. |
Reef is part of the scarp face of Wenlock Edge. A wonderful view where
the underlying rock type can be related to the surface topography. View
looks from Silurian Wenlock Series (limestone and shales); across
Llandovery Series (Hughley Shales and Kenley Grit) to the Ordovician and
beyond to the Precambrian Longmyndian and Uriconian. |
Spectacular massive high face of reef limestone where the reefs are at
their highest. Reef limestone is inter-bedded with nodular regular beds
which resemble a stone wall. Strong vertical joints split the reef face.
A prominent rounded stromotoporoid about 0.5 m above the base appears to
have been a trigger to reef building. The face is weathered and this
obscures the fossil content of the rock but crinoids tabulate and rugose
corals are present along with brachiopods and bryozoa. The visible
relationships between reef and shelf limestone and reef and mudstone are
very clear. Exposure is 15 m high and 28 m wide. Regarding the view the
Edge can be seen running south-westward (the escarpment being off-set by
faults along its length). The Longmynd and the volcanic hills of Lawley
Caradoc and the Bowdlers rise steeply in the distance while the rolling
topography of alternating resistant and less resistant grits and shales
reflects the underlying rocks. The position of the basal Llandovery can
be appreciated as can the line of the Church Stretton Fault running
between the Wrekin and the Stretton hills. |
Open access to the Ippikin's Rock view-point and to the footpaths on
Wenlock Edge. A path leads from the view-point to the right. A few
metres further on turn left along a much lesser used path which brings
you to the foot of Ippikin's Rock. Do not park in the car park of the
Wenlock Edge Inn without asking permission. Landlord likes custom but
isn't keen on field groups with muddy boots. |
LGS Yes. Designated as LGS as the site provides an excellent example
of a Wenlock Edge patch reef at its maximum development and allows easy
examination of the relationship between the reef and surrounding modular
and tabular limestone beds. |
Sedimentology/Stratigraphy/Geomorphology/Landscape |
| 0940 |
SO 573 968 (SO 571 967 on GIS) |
Upper Hill Farm (SE) -
Wenlock Edge |
Cutting (road/railway) |
Silurian: Wenlock Series: Wenlock Shales: Coalbrookdale Formation:
Apedale Member. |
Foot of the scarp slope of Wenlock Edge. |
This old railway cutting exposes grey/brown/green weak mudstones; easily
weathered and crumble to scree. Bedding is thin and irregular. Some beds
are more resistant and contain discrete larger rounded nodules. Along
the bank about 25 m from the N end there is evidence of alternating
resistant and less resistant rock layers; some strata are more
crystalline. Fossils are scarce; merely a few small brachiopods. There
are prominent diagonal joints and large nodules; general dip direction
is SE. Height of exposure 3-4 m and about 90 m is exposed along the
path. Reflects a tropical sea environment but one where the sea was
deeper and muddier than with the succeeding Much Wenlock Limestone. |
Open access along public footpaths. Nearest carpark is at Presthope
(NT). |
LGS Yes. Provides one of only a few exposures of the Apedale mudstones
(Wenlock Shale) and is important for interpreting the Wenlock Series
succession of the area. |
Sedimentology/Stratigraphy |
| 0941 |
SO 574 966 |
Lilleshall Quarry (SW end)
- Bourton |
Quarry (disused) |
Silurian: Wenlock Series: Much Wenlock Formation: Reef facies; and
Wenlock Limestone. Sheet SO 59 |
At
the top of the dip slope of Wenlock Edge; forming an elongated 'valley'
parallel to the crest. |
On
the north side the main face rises dramatically up to the road. From a
distance the relationship between reef and stratified limestone can be
appreciated as the ballstones and their effect on the surrounding rocks
is clearly visible. Lying on the ground are large blocks of limestone
which are often slickensided and mineralised with calcite. Crystals of
calcite are large well-formed rhombs forming aggregates. The link
between calcite mineralisation and faulting soon becomes apparent as a
few metres SE of the main face is a calcite vein some 350 mm thick which
runs diagonally across a broken ballstone at ground level. To the left
of this is a vertical shatter-zone where faulting has resulted in
calcite mineralisation and brecciated reef limestone. Between this and
another sub-parallel fault the rocks have been displaced downwards and
Lower Ludlow Shales appear at the top of a narrow 'pinnacle' of
limestone. Between the broken reef and stratified limestone dipping SE
at about 15° a 3 m wide section of weak stratified weathered rock with
thin beds of discontinuous calcareous nodules occurs. This seems to be a
rather atypical exposure of the down-faulted Lower Ludlow Shales altered
by the faulting and subsequently weathered. There are several features
of interest near the middle of the quarry. The floor is of grey fine
gently dipping limestone which has a palaeo-karst appearance. This can
be seen exposed on the north side amidst the quarry waste which
buttresses the faces. There are many fossils: surprisingly corals e.g.
Favosites gothlandicus; brachiopods e.g. spiriferids; rhynchonellids;
strophomenids; gastropods and a glabella of a trilobite (15 mm long).
Here the conditions were low energy marine with some evidence of a very
shallow sea even emergence because of trails and other signs of
bioturbation. The sediment was fine deposited as a limy mud. On the
south side of the quarry in this area are two separate 'stacks' of
limestone left after quarrying. One shows very clearly lower greyer
thicker strata divided from crystalline layers with shale partings by a
120-150 mm layer of shale. Rocks are dipping approx. SE at 10°. There
are fewer fossils here. The face is 9 m high. The second 'stack' is a
bit higher in the succession and consists of coarse grey crystalline
limestone |
Enter via a track opposite the works on the Bourton road. There are no
restrictions to prevent access although permission should be sought from
the Bardon Company at Lea Quarry. |
LGS Yes. This is an outstanding site. Not only is there a splendid
shatter zone with its effects clear to see but the Lower Ludlow Shales
become exposed in a most interesting way. The calcite mineralisation is
impressive and the massive blocks of limestone are unusual along Wenlock
Edge. Also the far end of Lilleshall Quarry is a delightful place with
all sorts of wildlife. |
Structure and Sedimentology/Stratigraphy |
| 0944 |
SO 579 971 |
Lilleshall
Quarry entrance |
Quarry (disused) |
Silurian: Wenlock Series: Much Wenlock Formation: Reef facies; and
Wenlock Limestone. |
At
the top of the dip slope of Wenlock Edge; forming an elongated 'valley'
parallel to the crest. |
This quarry has many interesting features. The high faces at the SW end
of the site give an impressive view of the inter-relationship between
ballstones and surrounding stratified limestone. These high near
vertical faces do not allow close examination and are better viewed from
a distance. However there are other more accessible places which display
splendid geological features. At the entrance to the quarry itself a
long exposure runs at right angles. Light grey fairly coarsely
crystalline thin slabs occur with olive siltstones. The former weather
brown and contain scattered crinoids some 100 mm across. There is much
clay between the layers. The colour of the crystalline limestones varies
from light brown to a deep grey and there is also variation sometimes
sudden in texture. Calcite is common often pink there being large and
well-formed crystals. Within the stratified limestone small ballstones
occur which result in what appears to be folding in the surrounding
rock. Further along the exposure there is more fine-grained muddy
limestone with paper shales grey in colour. A fault can be seen showing
mineralisation of 20-30 mm thick calcite with slickensiding and
brecciation of both rock and calcite. The fault has an E-W trend.
Dimensions: 70 m long and 4 m high. |
Enter via a track opposite works on the Bourton road. There are no
restrictions to prevent access although permission should be sought from
the Bardon Company at Lea Quarry. |
LGS Yes. LGS status because of the variety of features to be seen: ballstone within stratified limestone; crinoidal; crystalline limestone
contrasting with shales; effects of a fault. The whole quarry deserves
LGS status but there are separate sites which need to be described in
their own right. |
Fossils and Sedimentology/Stratigraphy |
| 0945 |
SO 581 974 |
Wenlock Edge -
Cliff and Roof of Presthope Tunnel |
Cliff |
Silurian: Wenlock Series: Much Wenlock Formation; and Coalbrookdale
Formation: Wenlock Limestone and Shales. Sheet SO59. |
Above roof of old railway tunnel through scarp slope of the Edge. |
A
thick sequence of inter-bedded mudstones and thin nodular limestones is
exposed at and above the tunnel entrance. These represent the Farley
Member of the Coalbrookdale Formation. They illustrate a transition
between the underlying mudstones (Apedale Member) and overlying Much
Wenlock Formation above. At the base of the cliff limestones are nodular
within thicker mudstones; higher up layers of coalesced nodules are
separated by thin shales. Colour changes from green/brown at the base to
grey/white at the top. Width of exposure is 10 m; height approx 15 m.
Fossils are scarce in the mudstones but the strata become more
fossiliferous with typical Wenlock fauna further up the cliff. This
reflects deeper muddier conditions becoming clearer and shallower in a
tropical marine environment. |
From Hughley road take footpath along Presthope cliff section and go
down the steps leading to the roof of the tunnel. Can also be approached
from the opposite direction along the old railway line from the
Ippikin's site. |
LGS Yes. Importance lies in the transitional nature of the lower series
(from underlying mudstones to Upper Much Wenlock Formation) and the
obvious White Much Wenlock Formation above. Talus gives representative
specimens. |
Fossils and Sedimentology/Stratigraphy |
| 0946 |
SO 5817 9743 |
Wenlock Edge -
Presthope cliff section |
Cliff |
Silurian: Wenlock Series: Much Wenlock Formation. Sheet 152 or SO59. |
Scarp slope of Wenlock Edge. |
Shows patch reef development in the Much Wenlock Formation and variation
in inter-reef limestone lithologies. The reef here is low and
discontinuous. Thin bands of shale are present. The inter-bedded
limestones are nodular or tabular occurring in fairly thin beds. Some
crinoid-rich beds are thicker. There is evidence of slickensided
surfaces indicating post diagenetic strike-slip movement along joints.
At the end of the section (nearest the Hughley road) there is clear
evidence of the bioherm causing the underlying beds to be depressed and
warped. The section is 50-60 m long; height variable up to 7-8 m.
Calcite mineralisation is often present. Fossils found include
reef-building corals and stromotoporoids e.g. Halysites Favosites and
many non-reef building organisms e.g. crinoids bryozoa and many
brachiopods; representative of a clear shallow tropical sea. |
From NT car park GR583975; approach from the Hughley road and use public
footpath along the section. |
LGS Yes. Its importance lies in the clear examples of small patch reefs
and their relationship with interbedded nodular and tabular limestones. |
Fossils and Sedimentology/Stratigraphy |
| 0949 |
SO 617 993 |
Much Wenlock |
Cutting (road/railway) |
Silurian: Ludlow Series: Leintwardine Beds. |
Track cutting next to road out of Much Wenlock into Corvedale. |
The rocks here are mostly olive mudstones with lenses of crystalline
grey limestone. There is much calcite (sometimes pink); large crystals.
The shales and mudstones are thinly bedded with irregular partings. The
exposure is about 40 m long and 5 m high. There seems to be a
significant boundary below which the rock is fragmented whilst above it
are more regular strata of thicknesses varying from 300 mm to 30-40 mm.
Dips are variable too; not consistent with the general SE dip of Ludlow
strata and with angles of inclination ranging from 18° to 45°. This may
be the result of faulting close at hand. Rocks are very fossiliferous;
there are many finely comminuted fossils in the more crystalline shelly
strata but preservation is better in the siltstones. Fossils include
Fuchsella amygdalina Camarotoechia nucula Salopina lunata and many
others. |
On
private land beside farmer's track into field |
LGS Yes. Designation because the site displays a good exposure of U. Leintwardine strata with a typical range of fossils which can be
studied; there are few such sites in the Much Wenlock area. It also
shows evidence of faulting and calcite mineralisation. From the
geological map Sheet 152 it can be seen that the exposure forms part of
a narrow rift valley. |
Fossils and Sedimentology/Stratigraphy |
| 0952 |
SO 717 928 |
Castle Hill Gardens (East)
- Bridgnorth |
Cliff |
Permian: Bridgnorth Sandstone. Sheet 167 (Dudley) - old map; different
nomenclature. New names from Toghill 1990. |
Sandstone cliff with caves on south side of River Severn |
In
the cliffs beneath the public gardens the sandstone cliff rises
impressively. Large scale trough cross-bedded units are inter-bedded
above and below with planar cross beds. There are many caverns; the
remains of excavated dwellings; and at the southern end one of these is
accessible and shows a three-dimensional section. |
Observable from public gardens belonging to Bridgnorth Council. The
outcrop stands some 20 or 30 metres back from the road and this area is
well maintained by the council as a publoic amenity. |
LGS Yes. LGS classification as it is the type section for the Bridgnorth Sandstone. Displays complex of trough and cross-bedded
sandstone units which represent westward-migrating draa dunes with
superimposed barchan and linear dunes. |
Sedimentology/Stratigraphy |
| 0953 |
SO 724 939 |
High Rock - Bridgnorth |
Cliff |
Lower Triassic: Kidderminster Conglomerate; lying on top of Permian:
Bridgnorth Sandstone. |
Summit of the sandstone ridge where there is a marvellous view
(especially) in winter towards Bridgnorth across the R. Severn. |
The dunes of the Permian Sandstone drop 70 m sheer to the road. There
are several crags by the path with exposed bedding planes. Continuing up
the path leads to exposures of the Kidderminster Conglomerate which are
excellent for close study. |
via public footpaths |
LGS Yes. A 70 metre cliff of Permian Sandstone topped by an easily
examined Lower Triassic Kidderminster Conglomerate combines with a
magnificent view. A geologist's delight! |
Sedimentology/Stratigraphy |
| 0955 |
SO 738 956 |
Rindleford
Quarry |
Quarry (disused) |
Lower Triassic: Kidderminster Conglomerate. Mostly the sandy facies |
Long vertical wall of former quarry near Rindleford Mill. |
At
first glance this sandstone could be mistaken for aeolian but a closer
look at the low angles of cross-bedding the scattered pebbles and the
more angular quartz grains will identify it as being fluviatile. There
are no beds of conglomerate visible at this point but the strata belongs
to the Kidderminster Conglomerate Formation. This is an extensive site
(at least 100 m in length) and the faces 9 m high. The quarry exploited
a thick coherent bed of nearly pure sandstone within the Pebble Beds. |
Beside public footpath |
LGS Yes. Excellent fluviatile features and located near similarly
excellent aeolian sites in Bridgnorth (as at Castle Hill gardens). The
section brings out well the difference between aeolian and fluviatile
deposits. |
Sedimentology/Stratigraphy |
| 0956 |
SO 733 958 (SO 732 958 on GIS) |
Worfe Bridge - Worfield |
Cutting (road/railway) |
Triassic (Kidderminster Conglomerate) over Permian (Bridgnorth
Sandstone); Toghill 1990. Map out of date regarding nomenclature. |
Just part of a roadside cutting from which the relief rises abruptly. |
On
the west side of the road north of the Worfe Bridge a cut section shows
cross-bedded dune Bridgnorth Sandstone with an undulating erosion
surface dipping gently to the NE. Above this is Kidderminster
Conglomerate (1 m thick) with clasts up to cobble size which fill
hollows in the erosion surface. The beds above are intermingled coarse
pebbly cross-bedded sandstone and conglomerate lenses. This is a very
informative site. On the east side of the road similar features occur
but not so clearly. However here the conglomerate itself is truncated by
a major parting with an erosion surface dipping 5° N cutting through
this basal surface. This section continues south with over 100 m of
interleaved cross- tangential- and trough-bedded sandstones. |
Beside A442. Limited parking near Worfe Bridge. |
LGS Yes. Clear demonstration of transition from aeolian deposition of
pure sand to fluviatile deposition of mixed sand and pebbles. Also
features of dune deposition are clear. A good site for teaching although
the main road makes large groups impossible. |
Sedimentology/Stratigraphy |
| 0958 |
SO 739 902 |
Quatford (Little Chef) -
Quatt Malvern |
Cutting (road/railway) |
Permian: Bridgnorth Sandstone. Toghill 1990. Nomenclature out of date on
Sheet 167. |
Vertical cliff. |
There are 200 m exposing dune sandstone. At the southern end is a
steeply inclined dune structure apparently dipping south and truncated
sharply by planar beds which apparently dip north at varying angles. The
section is impressive as are so many of the sandstone cliffs in the
vicinity. It reaches a max. height of approx. 10 m. Further north the
face is more broken but more steeply inclined dune beds are visible. The
cliff section demonstrates westwardly migrating sand dunes. |
Best viewed from the carpark of the Little Chef and the grass verge
opposite the cliff section. It is possible to walk along the foot of the
exposure but the scale is best appreciated from a distance. |
LGS Yes. Shows truncation and overlap of cross-bedded foresets within
westerly migrating sand dunes. |
Stratigraphy/Stratigraphy |
| 0960 |
SJ 542 133 |
Haughmond Hill
(S) - Uffington |
View |
N/A |
Viewpoint on south-facing slope of Haughmond Hill |
Views here are extensive and a geological panorama is presented. It is
an ideal spot to see the Wrekin; Clee Hills; Church Stretton volcanics;
Wenlock Edge; Long Mynd; and the Welsh Mountains. The site presents an
excellent opportunity to relate landscape features to the underlying
rocks. The immediate foreground is the southern tip of the North
Shropshire Plain and the Shrewsbury Coalfield area. |
Public footpath |
LGS Yes. Designation because of the range of Shropshire geological
features clearly visible can hardly be surpassed; and the relationship
between rocks and relief can clearly be demonstrated. |
Geomorphology/Landscape |
| 0962 |
SJ 543 134 |
Haughmond Hill
Trig. Point |
Crag |
Precambrian basaltic intrusion |
Forms a rounded ridge summit at the highest point of Haughmond Hill (152
m). |
The summit exposes a WNW-ESE dolerite dyke beneath and around the trig.
point. The rock is a medium crystalline greenish dolerite. As is usual
with basic intrusions; the surface weathers brown. Within the dolerite
are discontinuous; whitish; small veins; up to 10 mm across. They show
alignment in a NNE/SSW direction. Under a hand lens these veins seem to
consist of quartz and a black; bituminous material. It is possible that
they represent infilled tension gashes. |
Along publicly used track. |
LGS Yes. Designation because this site demonstrates a good example of a
Precambrian dyke forming the summit of Haughmond Hill; the trend can be
measured and there are interesting details e.g. possible tension gashes. |
Mineralogy/Petrology |
| 0963 |
SJ 543 149 |
Haughmond Hill
(N) - Uffington |
Track/roadside |
Precambrian: Wentnor Group: Bayston-Oakswood Formation: Darnford
Conglomerate. Sheet 152. |
On
NW flank of Haughmond Hill as the land goes down to the River Severn. |
This site has potential but in June it is difficult to examine the rock
closely. However; as is typical of Haughmond Hill; the strata are
vertical. The Darnford Conglomerate is displayed as an attractive
green/purple rock with pebbles which here are smaller than in some other
places; most clasts are to be measured in millimetres. It could be
described as pebbly grit. According to Pocock; 10% of the pebbles are
igneous. An interesting feature to be seen at this site is a smooth
surface dipping at only 45° and not consistent with the dip or its
immediate surroundings. Although this could be a joint it was thought
more likely to be a small fault plane. |
By
the side of B5062 and thus easy to reach. |
LGS Yes. LGS designation especially in association with site SJ544419.
Relatively easy access to what is a limited outcrop of one of the
important conglomerates within the Bayston-Oakswood Formation. |
Sedimentology/Stratigraphy |
| 0968 |
SJ 5925 0012 |
Harley Brook
confluence (on tributary) |
Stream/brook |
Silurian: Wenlock Series: Wenlock Shale: Buildwas Formation; close to
possible boundary with Coalbrookdale Formation (see Bassett) |
Deeply incised small tributary valley near confluence with Harley Brook |
25
m up the tributary; a 1 m high waterfall crosses the brook. The
waterfall appears to be the result of a hard nodular band which is tufa-covered.
The tufa protects the underlying thinly-bedded soft grey calcareous
shales and so preserves the waterfall. [A smaller fall (0.5 m) sits a
few metres upstream]. A typically rounded plunge pool has been formed
with sides curved by fluvial erosion. Unfortunately the strata here are
moss-covered so the detail is obscured. Below the fall and 10 m from the
confluence; a 5-6 m high exposure can be seen on a steep bank. Here
there is one prominent continuous nodular band dipping quite steeply in
an approximately southerly direction. At the top of the exposure are
smaller and more discontinuous nodules aligned approx. with the bedding.
The rest of the face consists of olive mudstones; sometimes showing very
thin bedding but elsewhere breaking more irregularly. These strata
contain many very small and fragmented fossils; mostly brachiopods. A
prominent near-vertical joint is visible. |
Although site is on land of Mr J Munslow; because of the steepness of
the banks access is easier from the field opposite belonging to Mr J
Brookshaw of Forge Farm; Harley |
LGS Yes. Designation because at or close to this site is the basal
boundary stratotype for the Apedale member of the Coalbrookdale
Formation taken to be immediately above the highest Buildwas nodular
limestone; according to Bassett. |
Sedimentology/Stratigraphy |
| 0969 |
SJ 592 002 |
Harley Brook
confluence |
Cliff |
Silurian: Wenlock Series: Wenlock Shale: Buildwas Formation. Sheet 152 |
River cliff at confluence of Harley Brook and tributary in Apedale |
The cliff exposure is 7 m high on the outside of a meander. The rocks
consist of shales siltstones of the Buildwas Formation. At the base of
the section are two layers of large non-continuous calcareous nodules
separated by irregular thin-bedded grey silty shales which weather
brown. There is a 20 mm thick white soft clay layer; probably bentonite;
above the lower nodules at about 1 m from the base. The middle of the
face consists of siltstones about 20 mm thick alternating with much
softer shaly mudstones. Here slumping is evident and stratification
somewhat chaotic. Joints cross these beds and there is possible
small-scale faulting. The top 2 m or so is unstable and bedding
extremely irregular; however; large slabs of and separated nodules can
be seen. Beds dip gently SE at no more than 10°. At the foot of the
cliff is much loose material excellent for fossil examination - fossils
are abundant and included several fine specimens of eoplectodonta
duvalii; an unidentified trilobite cephalon and much finely comminuted
material. |
Along brook from Forge Barn with permission of landowner. |
LGS Yes. Designation because the exposure demonstrates a large
accessible section through the Buildwas Beds close to the boundary with
the underlying Llandovery Hughley Shales and provides abundant fossils
typical of the formation. |
Fossils and Sedimentology/Stratigraphy |
| 0970 |
SJ 5925 0035 |
Forge Barn |
Stream/brook |
Silurian: Wenlock Series: Wenlock Shale: Buildwas Beds. Sheet 152. |
On
right bank of Harley Brook in Apedale where the softer mudstones and
shales form a valley between Kenley Ridge and Wenlock Edge. |
The exposure extends for approx. 20 m and forms the bottom 4 m of an 8 m
bank. Just above the level of the brook; are gently dipping blocks;
100-120 mm thick forming a distinct horizon. These are of grey
appearance and form a hard layer; being nodular in places and seem to be
limestone concretions; sparking when hit with a hammer. Below water
level are softer blue-grey mudstones which can be seen extending
half-way across the brook. Above the nodular layer are similar soft;
grey; shaly mudstones and about 3 m up the bank the mudstones become
more olive-brown and contain very small brachiopods. The exposure
mentioned in the literature at SJ 592003 was not visited because of a
torrential thunderstorm and very difficult conditions along the brook. |
On
private land; via brook or field. Wellies needed. |
LGS Yes. Designation because this is a good section through the lowest
strata of the Wenlock series; very close to the boundary with the
Hughley shales of the Llandovery. This boundary crosses the brook in a
number of places and this site should be studied with others in the
locality. The whole of the brook from the A458 to Hughley village is
designated an SSSI for its geological importance. |
Sedimentology/Stratigraphy |
| 0971 |
SJ 594 007 |
Domas |
Stream/brook |
Silurian: Llandovery Series: Hughley Shales. Sheet 152 |
In
deeply incised Harley Brook in Apedale; below Wenlock Edge. |
For 25 m there are intermittent exposures deep into the brook bed and up
the bank (to 1.5 m) of richly- and often parti-coloured soft shales
(brown/blue/green/purple). The highest face unfortunately stands beyond
an inaccessibly deep pool but from a few metres it can be seen as
clearly bedded with strata of varying but moderate thickness. Shales
contain well-preserved fauna including brachiopods up to 15 mm across.
The brook churns up from its bed large numbers of beautiful lumps of
shale which quickly break up into smaller fragments but are ideal for
examining fauna. |
On
private land in steep-sided and potentially dangerous brook. Not a site
for the faint-hearted but a very interesting one! Permission needed. |
LGS Yes. Designation because this site produces fine specimens of fresh
clean Hughley shale and a good well-stratified vertical face; access is
extremely difficult and its educational use for groups is therefore very
limited. |
Fossils |
| 0972 |
SJ 619 049 |
Leighton |
Stream/brook |
Quaternary: landscape affected by fluvio-glacial action |
Floodplain of the Severn featuring striking meanders |
This is a geomorphological site. The meanders on the Severn in the flood
plain here are outstanding. Sometimes they disappear under flood water
which covers the whole valley but usually they can be seen in the
context of the Severn valley; the mouth of the Ironbridge Gorge and the
hills flanking the valley. In particular; there is a mature meander with
a narrow neck; almost ready to be cut off to form an ox-bow lake. The
narrowing of the valley as it approaches the Ironbridge Gorge is clearly
seen and the first of the river terraces can just be made out from the
view-point. |
Visible from viewpoint at parking place by public road |
LGS Yes. Designation because the valley here demonstrates lateral
erosion and deposition by the river as it builds up its flood-plain.
This is also the place where ice-dammed waters accumulated and fluvio-glacial
sands and gravels were deposited prior to the cutting of the Ironbridge
Gorge. It is a unique and striking section of the Severn Valley. |
Geomorphology/Landscape |
| 0974 |
SO 484 965 |
Comley Quarry - Cardington |
Quarry (disused) |
Cambrian: Lower Comley: Lower Comley Sandstones and Limestones. Sheet
166. |
On
lower ground at N end of Little Caradoc. |
The best known section through the L. Comley Sandstone where green
glauconitic medium textured sandstone is seen dipping at 73° E. The type
section of the Lower Comley Limestones is at this site; a detailed
description of the divisions is referred to in Hains. There is a
discrepancy between what is supposedly present in this quarry and what
is readily visible; such is the extent of deterioration. Anyone visiting
the quarry even with some geological knowledge will be greatly
disappointed and is unlikely to be able to identify the horizons
described. |
Is
open to public road |
LGS Yes. Designation because of its undoubted importance as the type
section for the Lower Comley Limestones. Also the place where Lapworth
discovered the first L. Cambrian trilobite. However these scores are
based on what is supposed to be there. A student group would no longer
find this site interesting or helpful! |
Fossils and Sedimentology/Stratigraphy |
| 0977 |
SO 477 918 |
Soudley Quarry |
Quarry (disused) |
Upper Ordovician: Caradoc Series: Horderley (Soudley) Sandstone
Formation: Alternata Limestone Formation: Cheney Longville Formation.
Sheet SO 49. |
Quarry on the scarp slope of the SE-dipping Caradoc series; E of Soudley
Brook. |
A
massive face of Soudley Sandstone rises abruptly at the back of the old
quarry. Bedding is difficult to identify. The distinctive stripes in the
sandstone are easy to see although they are not as purple as seen in
buildings; probably due to weathering. Some fallen blocks are over 2 m
thick and crinoids are visible in places. The angle of dip is approx.
12° SE. There is a clear break about two-thirds up the face which
appears to be the boundary with the overlying alternata Limestone; this
is moss-covered and packed with brachiopods; mostly decalcified. This
boundary is almost inaccessible and dangerous to reach. Greig describes
the alternata Limestone as '3 ft 3 in. of green mudstone; generally
silty and shaly; with 3 bands of shelly limestone; 4 to 5 in. thick'.
Pieces of the shelly limestone can be found at the foot of the face.
Below the boundary; the Soudley Sandstone is rather broken and above the
strata consists of thinner beds; which then become thicker up the face.
The strata above the alternata Limestone belongs to the Cheney Longville
Flags but it isn't safe to examine them in situ. A section through the
strata is described in Greig; p.129. |
From public footpath entry to quarry is easy but examining the upper
faces is difficult and dangerous. |
LGS Yes. The only contact in the area between the alternata Limestone
and the Cheney Longville Flags. Also the brachiopod Heterorthis
alternata was first defined from specimens collected at this locality as
were several trilobite species. |
Fossils and Sedimentology/Stratigraphy |
| 0984 |
SO 490 956 |
The Wilderness - Cardington |
Quarry (disused) |
Ordovician: Caradoc Series: Chatwall Sandstone. |
Along the Wilderness sandstone ridge. |
Here exposures are limited by grass and nettles but are visible and able
to be examined to some degree. The dip is steep (about 70° or more) and
the sandstone is khaki in colour and medium grained. At the best
exposure the strata can be seen to be dipping nearly vertically along a
well-defined bedding plane. Here the rock is fossiliferous with good
examples of brachiopods e.g. Sowerbyella and Kjaerina. In a hollow on
the west side of the ridge are many loose fragments and larger blocks of
a variety of rock types including red Triassic sandstone and igneous
rocks e.g. dolerite. These presumably are glacial erratics. |
Beside public right of way in pasture |
LGS Yes. Exposure showing the presence of Alternata Limestone on the
crest of the Chatwall Sandstone escarpment. There are better exposures
of Chatwall Sandstone but this is an accessible site with the
fossiliferous interest and the excellent erratic material. In the light
of the demise of the nearby Netchley Quarry this could be developed into
a replacement. |
Fossils and Sedimentology/Stratigraphy |
| 0987 |
SO 500 900 |
Eaton Track |
Track/roadside |
Silurian: Wenlock Series: Coalbrookdale Formation: Apedale and Farley
Member: Homerian Stage. Stratotype for base of Upper Gleedon chronozone
of the Homerian |
Sunken track at foot of scarp slope of Wenlock Edge. |
Difficult to describe because although there are many sections of
exposed rock the condition of the site is very poor and most of the
exposures are covered in ivy. The fine grained limy mudstone can be seen
is irregularly bedded fairly soft and in places displays curved joints.
Some faces appear massive along vertical joint planes whereas others are
much more thinly stratified. Although careful geological work at this
site has established the base of the Gleedon Chronozone of the Homerian
Stage it would be extremely difficult to do this today. It is however
interesting to read the account of what is there even if the significant
features are now nearly completely obscured. |
In
itially along public track beside Eaton church but majority of site is
on private land (higher up) and notices specifically prohibit access to
geologists. |
LGS Yes. Designation because of the undoubted historical value of this
site in establishing stratigraphical boundaries in the Wenlock Series of
the Silurian. It is already recognised as a SSSI and is an
internationally important locality. The site is designated a standard
section for the Homerian Stage. The section also spans an important
junction between two zones based on graptolites |
Sedimentology/Stratigraphy |
| 0988 |
SO 505 942 |
Hillend - Cardington |
Natural exposure |
Cambrian: Wrekin Quartzite resting on Uriconian Quartz Porphyry. Sheet
166. |
A
sharp SW-trending quartzite ridge lies along the strike |
A
prominent exposure of white sugary rock which stains black or brown with
weathering. The strata dip steeply from 40°-50° SE. Texture is slightly
coarser towards the base and irregular jointing leads to a brecciated
appearance. Principal joints at 25° just E of N. There is some quartz
mineralisation on the surface showing slickensiding on the west side of
the ridge. The quarry at the north end of the ridge is used by the
farmer and not accessible. Although there is quartz porphyry underlying
the quartzite; exposures are hard to find and the evidence comes from
fragments at the surface on the west of the ridge top which show a pink
feldspar-rich rock with quartz crystals in a finer groundmass. |
On
private rocky pasture sitting above the public footpath. The substantial
quartzite quarry at the village end of the hill is used for farming
purposes. |
LGS Yes. Designation because the Wrekin quartzite is exposed very
clearly and sharply as a distinctive edge visible for miles and forms a
limited Cambrian exposure outcropping between two E-W trending faults.
The underlying intrusion of quartz porphyry (especially if a small
exposure could be revealed) is also interesting. |
Mineralogy/Petrology |
| 0989 |
SO 512 936 |
Gilberries Farm |
Stream/brook |
Silurian: Llandovery Series: Pentamerus Beds. SO 49. |
In
the valley of Heath Brook; east of Cardington Hill. |
Exposure is about 10 m long and up to 1 m in height; including above and
below water level. The bank is higher but is mostly covered with soil
and vegetation. The rock occurs as discontinuous slabs; is grey;
fine-grained and shaly and is overlain by glacial till. A little further
downstream the colour becomes purplish and some horizons are limy and
very fossiliferous with a mainly brachiopod fauna e.g. Pentamerus
oblongus. The dip is 10°-19° SE. |
In
brook bank beside public footpath. Wellies are advisable to gain close
up access. |
LGS Yes. Designation because this is a good exposure of Pentamerus Beds
which is reasonably accessible. Such exposures are not common in this
area and the site has potential for study. The typical fossil fauna can
be seen. Glacial drift cover is also clearly visible here. |
Fossils and Sedimentology/Stratigraphy |
| 0991 |
SO 539 927 |
Longville to Stanway Road -
Rushbury |
Track/roadside |
Silurian: Wenlock Series: Farley Member: Coalbrookdale Formation |
NW-facing scarp slope of Wenlock Edge. |
Several exposures from the foot of the hill to the top are exposed in a
road cutting which rises steeply from the road itself. Alternating fine
grained limestones and buff mudstones were easily visible; thickness of
beds varyies from 25-70 mm. The mudstones are weak and disintegrating.
Taken to be representative of the Farley Member. However although the
base of the overlying Much Wenlock Limestone is described as 'sharp' and
occurring where the first continuous and regular limestone bed appears
this was far from clear. Signs of nodular beds higher up in the sequence
were seen. There is a profusion of vegetation obscuring the exposures
and the site has clearly been deteriorating. There was a distinct
difference between what was actually observed at this site and what can
be seen according to the literature. |
Beside public road |
LGS Yes. Already a geological SSSI. The SSSI report points out that
these exposures allow correlations to be made between Shropshire's
standard sections for the Wenlock and overlying Ludlow Series.
Graptolites found here have been instrumental in dating the base of the
Wenlock Limestone. In addition their presence has provided a correlation
between the base of the Wenlock Limestone of Wenlock Edge and that of
the Ludlow anticline. This correlation is based on the presence of the
graptolite Monograptus ludensis which was once taken to be an indicator
of the base of the Ludlow Series. |
Sedimentology/Stratigraphy |
| 0992 |
SO 5462 9055 |
Hopescross |
Quarry (disused) |
Silurian: Aymestry Group: Upper Ludlow Shales. Sheet 166. |
At
foot of the dip slope of Wenlock Edge. |
The quarry lies in a scarp slope of harder rocks trending WNW to N. The
left-hand face appears to be a WSW trending joint surface and shows a
compactly bedded siltstone with fossiliferous limestone bands.
Weathering has now revealed fine depositional detail including some
slump bedding. This left-hand face is truncated on the right by a small
displacement N-S fault to the right of which are a number of smaller
subsiduary faces. The quarry floor is flat and free of rubbish and shows
relatively little talus; what there is is very fossiliferous. It is
likely (see ref. 1) that this quarry shows in its lower part beds of the
Aymestry Group becoming transitional into Upper Ludlow Shales. Main face
9 m high and 20 m long. Brachiopods; Bryozoa; Gastropods; Tentaculites.
Three metres of bedded silty limestones with some siltstone beds
overlain by 6 m of bedded calcareous flags with limestone beds and
nodules. The overall impression of this quarry is that the faces are
clear and easily examined. Siltstones are irregularly bedded in places
with clay whilst elsewhere on the face the bedding is thin and distinct.
The dip is approx. 12°. Higher up the beds are thicker and more regular.
There is a prominent joint or fault in the right-angled corner. |
On
private land via a gate into a pasture. From road junction on B4368 at
Hopecross (SO548905) follow minor road to north; bending NW; quarry is
on LHS after 200 m. Limited parking; best on main road B4368. |
LGS Yes. Shows the transition between Aymestry Group limestones and
calcareous Upper Ludlow Shales in an exposure that is in good condition
with fine sedimentary detail some slumping; slight faulting and several
fossiliferous bands. |
Fossils and Sedimentology/Stratigraphy |
| 0993 |
SO 5685 9845 |
The Leasowes - Hughley |
Stream/brook |
Silurian: Llandovery Series: Hughley Shales and Wenlock Series: Buildwas
Formation. |
Along Hughley Brook at the foot of Wenlock Edge. |
At
this site the lithological change from Hughley Shales to Buildwas
Formation is seen in a colour change from mottled green grey and purple
to olive-buff and grey above. The transition over a metre or so is
accompanied by a decrease in the number of hard siltstones in the
sequence and replacement by calcilutites and nodules (Bassett et al.).
Although it was possible to see the Buildwas strata there seemed to be
no sign of the purple Hughley Shales and the boundary could not be
convincingly identified. The strata dips 15° E and a distinct horizon
with nodules of hard grey limestone was seen. The nodules were fine
grained and up to 750 mm in length; some were rounded. A boulder ridge
crossed the brook in one place. Above were thin irregularly-bedded soft
mudstones dissected by joints (brown and olive in colour). At the top of
the bank the rock was very weathered and crumbling but full of tiny
brachiopods. Below the nodular layer there was a more shaly mudstone;
grey and splits irregularly. There was no sign of any even slightly
purple shales and without damaging the bank further attempts to
establish the position of the boundary (said to be 50 mm wide) had to be
abandoned. A white soft clay (possibly bentonite) was observed 20 m
downstream. |
Via fields in private ownership |
LGS Yes. Designation because this is a globally significant site in one
of the most important SSSIs in the county. The stratotype section (of
international importance since it defines the Llandovery/Wenlock
boundary) is also the base of the Buildwas Formation and is coincident
with the stratotype base of the Wenlock Series and its lower
Sheinwoodian stage. There is also a rich fossil fauna including
graptolite zone fossils. |
Sedimentology/Stratigraphy |
| 0994 |
SO 573 987 |
Hughley Brook - Gippols
Dingle (SW) |
Bank |
Silurian: Wenlock Series: Wenlock Shales: Buildwas Formation. Sheet 152.
Between Harley and Hughley the brook is considered the type area for the
Buildwas Formation. |
At
confluence of Hughley Brook and a tributary from the NW. |
A
good exposure of alternating blocky (250 mm thick) horizons and slightly
recessed softer layers (150 mm). The exposure is 3-4 m high and extends
10 m in length. The thinner layers consist of olive shaly mudstones with
abundant tiny fossil fragments (even complete specimens) but (although
crammed in the rock) they are not easily identifiable except with expert
knowledge. The resistant blocky layers are hard and crystalline mid-grey
in colour and clearly calcareous. At the base of the exposure the shales
become more tabular and lime-rich. The strata dip at about 20° SE. This
exposure is the most calcareous of the ones seen in the locality. |
On
private land down tributary of Hughley Brook; 10m W of public bridleway |
LGS Yes. Designation because this is an excellent example of the Buildwas Formation within its type area; one which can be studied easily
and close to a public bridleway. |
Sedimentology/Stratigraphy |
| 0995 |
SO 5745 9904 |
Hughley Brook - Gippols
Dingle |
Stream/brook |
Silurian: Llandovery Series: Hughley Shales and Wenlock Series: Buildwas
Formation |
At
south end of Gippols Dingle above Hughley Brook. |
Here the junction with the overlying Buildwas Formation is seen. There
is an upward passage from predominantly purple to bluish-grey mudstone
within about 0.5 m. It is a brookside cliff 3-4 m high and extending
for 8 m or so. The base of the exposure consists of mainly purplish
mudstones with occasional much harder discontinuous layer of blocks up
to 0.75 m long. Below that lies another horizon containing a few
scattered blocks about 400 mm across. The mudstone bedding is thin and
irregular with some slumping. At 2 m above the base lies a more
continuous layer of nodules; some are rounded and others squarer. 3.5 m
up from the base there is evidence of another nodular layer. There are
several near-vertical joints visible. The mudstones at about the 2 m
level are olive brown though the true colours are hard to ascertain
because of the covering of algae. The latter mudstones probably belong
to the Buildwas Formation and the lower strata to the Hughley Shales but
the actual boundary could not be accurately determined. Dip approx 20°
SSE. |
Down tributary of Hughley Brook 60 m S of public footpath on private
land. |
LGS Yes. Designation because at this site is the junction between Llandovery Hughley Shales and overlying Wenlock Buildwas Formation.
Although this is not the standard section it is an important exposure of
this boundary along Hughley Brook. |
Sedimentology/Stratigraphy |
| 0996 |
SO 5855 9955 |
Rowley Farm
(WSW) - near The Gippols |
Stream/brook |
Silurian: Wenlock Series: Buildwas Beds. Sheet 152. |
On
the bank of Harley Brook on the lower land between Kenley Ridge and
Wenlock Edge in Apedale. |
The brook exposure on the outside of a meander is 5 m long up to 0.5 m
high and also goes below water level. Small limestone nodules are found
both here and scattered upstream. The rock consists of a grey
fine-grained weak shale which includes fragments of very small
brachiopods. |
Near public footpath. |
LGS Yes. Designation because this is a valuable site providing
information for establishing the Llandovery/Wenlock boundary along the
brook and should be studied with other sites nearby. |
Sedimentology/Stratigraphy |
| 0997 |
SO 5865 9970 |
Rowley Farm (W)
- near The Gippols |
Bank |
Silurian: Wenlock Series (near Llandovery junction): Buildwas Beds.
Sheet 152 |
On
low lying ground along Harley Brook in Apedale. |
Gently dipping grey-brown siltstones are exposed just above brook level
which here have a flat slabby appearance. The exposure is very difficult
to examine in detail because of a deep water pool just in front of it. A
large 80 mm mould of a fossil orthocone was found in the siltstone here. |
On
private land. Difficult to examine closely because of depth of brook;
wellingtons needed. |
LGS Yes. Designation because this is a useful site for piecing together
the evidence to establish the Llandovery/ Wenlock boundary in this
locality. |
Sedimentology/Stratigraphy |
| 1000 |
SJ 256 298 |
Racecourse Quarry -
Oswestry. |
Quarry (disused) |
Carboniferous: Namurian: Cefn-y-fedw Sandstone (Millstone Grit) |
|
Old quarry with much undergrowth; some limited sections currently
accessible. Beds of variable sandstone - very hard to very soft; thick
to thin layers of fine-grained to coarse and pebbly sandstones. 9 m wide
X 10 m high X 5 m deep. Brown to cream variable quartzitic silts;
sandstones & grits. Some beds appear to be chert cemented. Also leached
or decalcified layers with fossil casts. Casts of productus sp. and
spirifer sp. brachiopods. Quartz predominant; some calcareous cemented
sandstones. Dip 25° E. Part of huge deltaic complex of Millstone Grit
deposited in shallow water high energy environment. |
From Oswestry take B4580 to Rhydycroesau; at cross-roads after 2 miles
take left turn sign-posted Racecourse Car Park. After 3/4 mile fork
right |
LGS Yes. Part of the huge deltaic complex of Millstone Grit deposited
in shallow water high energy environment. |
Fossils and Sedimentology/Stratigraphy |
| 1001 |
SJ 265 213 |
Pen-y-Foel Lane -
Llanymynech. |
Cutting (road/railway) |
Ordovician: Caradocian |
Exposure is on 'leeward' side of roche moutonée |
Dark greenish-grey partly indurated shales with thicker (up to 150 mm)
flaggy sometimes micaceous and/or silty mudstones. Poorly developed
jointing seen in places. A new exposure 5 m X 2 m and unweathered
appeared in October 1996 with similar lithology 30 m wide. New exposure
yielded several brachiopods and indeterminate fossils; dip 78° NE (on S.
flank of Berwyn Dome). Close to unconformity with overlying Lower
Carboniferous. PALAEOENVIRONMENT: Deep water facies on fringe of Welsh
Basin. |
From cross-roads in Llanymynech take Oswestry road but fork left after
250 m. Exposure is then 120 m along lane. |
LGS Yes. Good section of Caradoc mudstones |
Sedimentology/Stratigraphy |
| 1004 |
SJ 275 255 |
Savin railway
cutting |
Cutting (road/railway) |
Carboniferous: Namurian: Millstone Grit (Cefn-y-Fedw sst.) |
Small fault scarps; well delineated; a short distance north along
SJ27752560 - SJ27902600 (L). Also see Geol. Survey map Sheet 137 |
A
series of intermittent exposures of variable hard to soft sandstone and
siltstones with some shaley partings. Some quarrying and enlargement of
the cutting on east side. Total section along FP extends from 120 metres
to 260 metres from road access point. There are two main locations: (a)
200 m north of road and (b) 120 m north of road. Further intermittent
exposures of sandstone and siltstone between. Locality 'a' has good
exposures of hard white fine-grained sandstone with some calcareous
bands and appears to be leached in places. Beds vary from thin (20-30 mm
thick) to thick (1 m). At south end can be seen an undersurface of a
reddish-brown hard rounded pebble bed. Locality 'b' has fewer features;
mainly massive white fine-grained sandstone with some … (entry
incomplete) |
From A5 from Shrewsbury then B4396 to Llynclys crossroads at SJ282241.
Continue over on A495 for 1 km; turn right at Whitehaven on minor road
for about 1 km northwards; passing 'Sweeney Fen' on LHS. Take first
turning left along lane for 200 m in dip and park on narrow verge just
past cottage on RHS. Parking space is very limited. Footpath is ROW;
some minor dumping. Access is via ROW as marked on SJ22/32. |
LGS Yes. The Savin Railway Cutting is designated a LGS as the most
complete section available of the lower Cefn-y-Fedw Sandstone in NW
Shropshire; and for its demonstration of marginal deltaic sedimentation
and diagenetic processes with relevance to educational and scientific
studies. Itinerary; education; schools especially re- local interest
use. |
Sedimentology/Stratigraphy |
| 1005 |
SJ 306 009 |
Lower Wood
Dingle |
Stream/brook |
Ordovician: Llandeilo: Meadowtown Formation; Ordovician: Llandeilo:
Rorrington Shale Formation |
|
|
Proceed to Meadowtown on minor roads S of B4499. Note site of… (entry
incomplete) |
LGS Yes. This location offers an accessible alternative for the widely
publicised; but now unuseable; Meadowtown Quarry - the type locality for
Meadowtown Formation within the Ordovician of the Shelve Inlier; with
the added bonus of a section through the overlying Rorrington Shale
Formation. The site designated a LGS to ensure continuation of this
accessibility for teaching and research purposes. |
Fossils and Sedimentology/Stratigraphy |
| 1006 |
SJ 353 146 |
Alberbury Road
cutting |
Cutting (road/railway) |
Permian: Alberbury Breccia (ref.1); Permian: Bridgnorth Sandstone |
Cutting is through ridge formed of more erosion resistant rocks; this
ridge may be truncated by faults |
For much of its length the sides of this cutting are obscured by
vegetation and only at the western end are there visible and examinable
exposures. These hint at the potential hidden beneath the vegetation
cover. On the south side is a good section of red fluviatile sandstone;
fine grained with with fine cross laminations. At its top is a clear
erosion surface with a small wash-out and this in turn has an eroded top
to be succeeded by a coarse grain stone which leads upward into mixtures
of sandstone and conglomeratic breccia. Dip is to the north-east and the
section is partly replicated on the north side with thick fluviatile
sandstone and lenses of conglomeratic breccia. Also on the north side
there is a down-faulted block of paler pebble free sandstone; 3 metres
wide; suggestive of the overlying aeolian Bridgnorth Sandstone. Cutting
is 130 metres long and; on average 4 metres high. Exposure at west end
on south side is 10 metres wide and 4 high. Exposure on north side is 15
metres long and 4 high. No fossils found. Uniform dip ca. 15° NE. |
On
main road heading west through village. There is considerable danger
within the cutting from passing traffic; only the section on the south
side at the western end can be safely examined. Limited parking |
LGS Yes. The cutting designated a LGS for its potential as a site
showing the sedimentary features of a high energy fluviatile regime so
demonstrating the extensive and rapid erosion which must have taken
place at the end of the Carboniferous period. |
Sedimentology/Stratigraphy |
| 1007 |
SJ 360 143 |
Alberbury |
Track/roadside |
Permian: Alberbury Breccia (ref.2); Carboniferous: Erbistock Group:
Alberbury Breccia (ref.1) |
The Alberbury Breccia and associated rocks; being relatively erosion
resistant; form a marked E-W ridge between Alberbury & Rowton. This has
a stepped cross-section reflecting effects of softer strata according to
ref.1 |
The southern edge of the car park exposes a well bedded and distinctly
tabular sequence of dark red weathering breccia. Individual blocks are
widely deployed in the old stone walls for walled garden houses and the
church. |
Centre of village just north of Shrewsbury road. Car park by village
hall; permission should be sought |
LGS Yes. This location designated a LGS as the most easily accessible
exposure of the distinctive Alberbury Breccia which so clearly
demonstrates the extensive and rapid erosion which must have taken place
at the end of the Carboniferous Period. Potential use for small parties
with supervision. |
Sedimentology/Stratigraphy |
| 1018 |
SJ 610 102 |
Overley Hill |
Cutting (road/railway) |
Precambrian: Uriconian; rhyolites |
|
Construction of the A5 by-pass has created a road cutting revealing 100
metre long and 3 metre high sections in Uriconian Rhyolites. The faces
are fresh and unweathered and show fine texture and a 3-D ramification
of slip and joint planes. The exposures are within the same fault block
as that of the Lea Rock inlier described as red and purple rhyolites
with flow-banding and spherulitic structure. In conjunction with the
near-by Leaton Quarry this site relates to the Precambrian rhyolite/tuff
fabric of the Wrekin hill. Report of 15/01/2002 (Christine Rayner): A
relatively fresh exposure of mainly pink rhyolite with some grey tuffs;
often brecciated along fracture zones. The north side was examined as
the south was in dense shadow with detail hard to see. The rhyolite
displays excellent flow-banding and spherulitic structures have been
recognised in the rock. The exposure is broken by much faulting as well
as the shattering due to excavation for road construction. Much slippage
is evident; resulting from the position of the exposure in a fairly
narrow fault zone; part of the Church Stretton fault system. Many near
parallel faults can be identified and also larger; curved sheared
surfaces. Slickensiding occurs as do a number of near vertical mineral
veins which appear to contain barytes with hematite; the latter giving a
purple hue to the surfaces in places. The exposure demonstrates a series
of bedded lavas; the dip being at 40° SW. |
By
way of the ‘Shropshire Way’ official public foot-path which crosses the
A5 by-pass at the eastern end of the cutting. Some danger from proximity
of fast moving traffic; at quiet times a vehicle could be parked |
LGS Yes. A conspicuous road-side feature on the A5 by-pass showing the
rock (rhyolite) of which the Wrekin Hill (dominant on the sky-line to
the south) is mainly composed. The site designated a LGS in recognition
of a latter-day aesthetic juxtaposition. The site has intrinsic worth
for the freshness of its exposures which clearly demonstrate the
internal shattering which takes place in a large viscous rhyolite lava
flow as it slowly cooled and solidified to a brittle glassy consistency. |
Mineralogy/Petrology |
| 1020 |
SJ 638 027 |
Ackland's
Coppice |
Track/roadside |
Silurian: Tickwood Beds and Wenlock Limestone. Dip 5° SSW. Apparently
conformable transition between stages |
Deeply incised stream just to south |
The lower 15 metres of the section shows grey argillaceous limestone
weathering brown. This is generally massive but irregularly bedded with
a nodular component. There are a number of distinct shale bands; one of
which lies immediately above the pronounced terrace which has been
engineered at mid-height. Some strong joint planes are present cutting
across nodules. Only a sparse fauna is present. The terrace is cut just
below the thickest of the shale bands - some 250 mm. Above; the
limestone character changes to become distinctly crystalline although
still nodular and irregularly bedded. This limestone is notably
fossiliferous; especially a scattering of large corals. It is here
considered that the terrace marks the transtion between lower Tickwood
Beds and Wenlock Limestone. 170 m wide; lower part 15 m high to terrace;
above terrace 4 m of rock then 10 m graded slope. Sparse brachiopods &
trilobites in Tickwood Beds. Rich fauna of corals; strophmenoids;
gastropods; etc in Wenlock Limestone. |
Along the A4169 Much Wenlock to Buildwas road; about mid-way along the
newly excavated cutting |
LGS Yes. The site designated a LGS for its vivid demonstration of
changes in lithology and fauna between Tickwood Beds and overlying
Wenlock Limestone facies within the Wenlock Series; for which this
general area provides the International Standard. (It may provide a
substitute for the SSSI of Farley Dingle insofar as this was affected by
the recent road-works.) Itinerary; A-level studies; limestone
environments & fossils |
Fossils and Sedimentology/Stratigraphy |
| 1022 |
SJ 643 096 |
Ercall Hill |
Quarry (disused) |
Precambrian: Uriconian Volcanics. Cambrian: Wrekin Quartzite: Comley
Beds |
Ercall Hill 65m |
At
the southern end of the Ercall are 5 quarries; now disused; which are of
great geological interest. The unconformity between Cambrian and
Precambrian rocks is exposed. Radiometric dating of the latter;
particularly the granophyre; generates controversy about the absolute
age of the base of the Cambrian. A variety of igneous rocks; rhyolite
lavas and pyroclastic materials; dolerite dykes and the distinctive pink
boss-like intusion of granophyre are exposed. The sedimentary rocks
include conglomerates; breccio-conglomerates; quarz arenites and
glauconitic sandstones/siltstones of Lower Cambrian age; typical of a
sequence deposited during a marine transgression. The upper quarries
provide excellent opportunities to examine rock relationships; fault;
joint structures and dip/strike. Many smaller scale sedimentary
structures can be observed; e.g. ripple marks; cross bedding;
fining-upward sequences. Igneous flow-banded and spherulitic structures
are present in the rhyolite. In addition to the quarries which are a
SSSI; the rest of the Ercall is of geological importance. At the N end;
close to the M54; small exposures of rhyolitic tuffs can be seen and
persistent searching on the hillside to the west of the main footpath
brings evidence of white kaolin clay weathered from feldspar in the
igneous rocks. Car parking areas on the west side make use of small
former quarries in the granophyre. The view points at the top of the
hill by the main footpath provide the opportunity to relate the Ercall
rocks with the younger rocks to the east. |
Open access. Car parking at the Forest Glen opposite the Wrekin but
there are small car parks along the west side. |
LGS Yes. An outstanding locality with easy access designated a LGS in
its entireity as it exemplifies a range of rocks and structures
reflecting a calc-alkaline volcanic environment and subsequent marine
transgression. Even more important are the visible exposures of the
Precambrian/Cambrian unconformable boundary. Good for large parties.
Scope for varying levels of interpretation. Useful for a study of rock
relationships and a range of igneous and sedimentary rocks /structures. |
Structure and Sedimentology/Stratigraphy |
| 1024 |
SJ 645 087 |
Maddock's Hill
Quarry |
Quarry (disused) |
Ordovician: Tremadoc: Shineton Shales; intruded by Camptonite. |
|
The material extracted from this quarry is usually identified as
Camptonite and described as a thick sill intruded into Tremadoc age
Shineton Shales. The site has long been known as a collecting ground for
graptolites; particularly Dictyonema; examples of which can be found
among the shale debris. The quarry better displays the physical effects
consequent upon the forcing of an igneous intrusion into bedded shales;
the latter are locally baked but more impressive tongues and pipes of
Camptonite are evident and there is much contortion and over-turning of
the country rock. This is less marked at the NE end of the quarry where
basal Carboniferous Lydebrook Sandstone can be seen. Graptolites esp.
Dictyonema flabelliforme. In this area Shineton Shales dip ca. 10° SE;
the intrusion has caused a very local increase in dip to near vertical
or even overturning in the SE corner behind the large vertical ‘wall’.
Exposures of Camptonite are massive and well jointed. The outcrop has a
SW-NE trend parallelling the major faults in this area. There is an
unconformable cover of Lydebrook Sandstone marginally conglomeratic at
the NE end of the quarry. |
From Forest Glen take road NE to Little Wenlock; access to edge of
quarry by public footpath |
LGS Yes. The site designated a LGS as a long established collecting
ground for the characteristic Dictyonema graptolite; its display of a
wealth of features consequent upon a major intrusion into shales and for
its demonstration of the major unconformity at the base of the
Carboniferous in this area. Its accessibility and very generous
dimensions are particularly relevant to a teaching situation with large
groups. |
Fossils and Sedimentology/Stratigraphy |
| 1044 |
SO 292 833 |
Bicton (NNE) - Clun |
Quarry |
Silurian: Clun Forest Formation (ref.1) |
|
This quarry has recently been re-excavated for hard-core which is now
piled up against the main face and this is much broken. General dip is
WNW (300°) at around 20° with local steepening and some flexure. The
lowest part of the succession is to the right beyond the area of
excavation. Here are 1.5 m of massive bedded siltstone containing a
single elliptical ‘cobble’ adjacent to a zone of apparent slumping. This
is succeeded by 2 m of irregular flaggy bedding with small localised
disturbance of the bedding. There is then a 1 m thickness of slumping of
an intensity which approaches a mass debris flow. There follows 4 m of
alternating massive and flaggy beds with a 20 mm thick band of
Platyschisma helicites in situ. A further 6 m of beds are exposed in the
upper part of the excavated section where at least one 50 mm thick band
of Platyschisma is found in situ. To the left and below is abundant
talus from which was recovered further examples of Platyschisma up to 80
mm thick; a case of fine ripple marking with an amplitude of 7.5 mm and
examples of sole markings. The mapping of ref.1 places this locality on
the boundary between Cefn Einion and Clun Forest formations. It is here
considered that the locality lies wholly within the basal part of the
Clun Forest Formation previously known as the Green Downtonian. (A
second visit in Sept.1997 confirmed presence of Clun Forest Formation
with examples of Platyschima beds; re-survey made 3/10/1997). Exposures
1 to 4 m high and up to 5 m wide. |
Best approach is by public footpath from T-junction in Bicton at
SO290828; this traverses the flank of the ridge leading down to the
Bicton quarry where there are numerous small exposures of Downtonian.
Quarry is alongside a public footpath but neither this fact nor this
report should be taken as meaning permission is not required. Parking in
Bicton at T-junction; all other in Clun. |
LGS Yes. Lying just above the significant Ludlow/Pridoli boundary
within the Silurian System this site designated a LGS as showing
evidence that gross changes occurred in sedimentary conditions at that
boundary. Some value for further research is here ascribed to this site. |
Sedimentology/Stratigraphy |
| 1047 |
SO 310 740 |
Holloway Rocks - Stowe |
Natural exposure |
Silurian: Rhychonella and Chonetes Beds of Stamp (ref.1). Silurian:
Whitcliffe Beds or Cefn Einion Formation of current nomenclature |
Glacial features including moraines; incipient corrie formation; hanging
valley and moraine dammed pool |
The locality comprises about 1 sq.km of hillside best examined from the
public bridleway leading from Stowe Church to Holloway Rocks. Between
the church and the first gate are numerous small exposures in
bioturbated grey siltstone which show mainly Fuchsella & Camarotoechia
and correspond to Rhynchonella beds of Stamp (ref.1). Past the gate a
quarry gives good examples of typical fauna of these beds with
Serpulites longisimus particularly prevalent and Protochonetes
ludloviensis specifically absent. The track then ascends steeply to a
second gate and stile beneath the steep slopes of Holloway Rocks. Here
the rock now shows the full complement of brachiopods typical of Upper
Whitcliffe beds in this area; viz. Protochonetes; Camarotoechia &
Salopina lunata; these beds now continue right to the summit of Stowe
Hill above where they are; again typically; yellow weathering. It is
from the position of the stile that the glacial features may best be
appreciated. The frost-shattered exposures of the scarp above which
sweeps round towards the west suggests the early stages in corrie
formation; hidden around a corner; also to the west; is a small stream
whose bed has been truncated to form a hanging valley feature. Most
notable are the crests of three distinct moraine ridges which trend SW
towards the main valley of the River Teme below (various moraines
impinge upon the road in this valley and a good section of morainic
material can be seen in the bank excavated behind Mill House at
SO310729). Behind the three moraine ridges is a small perfectly
circular pool (at SO311742) evidently impounded behind these moraines on
the ‘corrie’ floor. Overall the view southwards from here is impressive.
The hills across the river valley occupy ground mapped by Holland in the
1950's (ref.2); in particular the observatory identifies Llan wen Hill
which provides the type section for the uppermost Whitcliffe beds in
this area. Geological Summary (with keywords). Lithologies: siltstones;
occasionally calcareous. Palaeontology: limited fauna of brachiopods;
bivalves; orthocones and (Serpulites). Structure: bedded strata dips
gently to NE forming a scarp feature; this has been over steepened with
beginning of corrie and hanging valley formation. Palaeoenvironment:
sediments laid down on shelf/basin slope below wave base but shallow
enough to suffer bioturbation and to accumulate some allogenic fauna. |
Best from Stowe Church adjacent to which is a car park. Access via
public bridleway. |
LGS Yes. The area designated a LGS on account of its clear
demonstration of the principal glacial features of corrie and moraine
with obvious relevance to recent ice ages. It also displays an
informative section through a 150 metres thickness of shelf slope
sediments. |
Fossils and Sedimentology/Stratigraphy |
| 1049 |
SO 314 797 |
Rock of Woolbury - Clun |
Quarry (disused) |
Silurian: Cefn Einion Formation (upper part) (ref.1); Silurian: Upper
Ludlow (Upper Whitcliffe?) Llan-wen beds (ref.2) |
|
The site is an extensively quarried depression now very much vegetated.
Visible rock faces are mainly confined to the northern margin where a
line of buttresses trends NE-SW varying in height from 2 to 8 metres.
These show a generally alternating sequence of calcareous siltstones and
mudstones of 50 to 200 mm thickness and somewhat irregularly bedded.
However because weathering has been prolonged the display of sedimentary
detail is exceptionally fine with cross and convolute lamination
climbing ripples mega ripples swale bedding and boudin(?) formation all
identifiable. The band of well jointed compact siltstone with false
bedding identifed by Holland in the middle of the Llan-wen Hill beds
(ref. 2) appears to be present. There is also appreciable variety in the
range of lithologies. Some faces would be ideal candidates for recording
a stratigraphical log. Buried beneath a veneer of moss and loose
vegetation are extensive areas of talus and loose blocks which show
abundant examples of scattered fossils usually decalified but entire in
freshly broken material. There is adequate material to allow for the
recording of a quantitative fossil list. Overall area is roughly
rectangular 250 metres by 100 metres. The northern rim 250 m long
displays several buttresses 2 to 8 metres high and 2 to 25 metres wide.
There are numerous other small exposures. Indications of a diverse fauna
with scatterd brachiopods bryozoa and serpulites. Possibilities for an
extensive collection to show an Upper Ludlow fauna. Gentle dip around 5°
SW. ‘Evidence of shallowing in a general irregularity of bedding
frequent current bedding and occasional ripple marks’ (ref.2). |
The quarry is totally surrounded by a plantation; mainly fir but small
oak near quarry rim. Best approach is by road from Clun via Woodside
towards Obley taking a north going track into the plantation from the
sharp corner at SO315793. This track bends to the right after 250 metres
and in a further 140 metres a side track leads downhill in a NNE
direction; after 80 metres take a narrower track through fir trees to
quickly reach the eastern side of the quarry where access is easiest.
Whilst the area appears generally much used for walking and horse riding
there are no public footpaths marked on OS maps and right of access
should not be assumed. Permission of owner(s) should be obtained
beforehand. Ownership has not yet been established. There is obvious
loose rock in the quarry faces and hard hats should be worn. There is
absolutely no reason to hammer the quarry faces where detail has only
become apparent after years of weathering. Only limited parking at the
corner SO315793. All other in Clun. |
LGS Yes. The quarry known as the Rock of Woolbury designated a LGS on
account of: (1) its wealth of sedimentary detail in a sequence of
shallow water siltstones; (2) its research potential for a full fossil
list of the Upper Cefn Einion Formation in this area; (3) its possible
uniqueness in the demonstration of a lithological and faunal change
within the Cefn Einion Formation of this area; prior to the major
changes at the Silurian Ludlow/Pridoli boundary. |
Fossils and Sedimentology/Stratigraphy |
| 1050 |
SO 318 837 |
Hoar Wood - Bury Ditches -
Clun |
Track/roadside |
Silurian: Cefn Einion Formation and Clun Forest Formation (ref.1);
Silurian: Upper Whitcliffe and Downtonian; Silurian: Upper Ludlovian and
Pridoli |
|
The section forms the east bank of a roughly N-S track. The dip is to
the south and the section is best examined in ascending sequence from
north to south beginning at a pronounced bend in the track. Just to the
east of this a small quarry shows typical bioturbated and rather
featureless grey siltstones of the Cefn Einion beds. In distinct
contrast the first exposure of the section is of sheet-like deposits of
allogenic fossils which include brachiopods; gastropods; trilobites and
occasional ostracodes. The next 200 metres expose a rich sequence of
bedded units showing sole marks; rippling; erosion surfaces all
indicative of a high energy environment which was probably above storm
and/or wave-base and shallowing. There then occur a number of horizons
containing Platyschisma & Modilopsis; one bed of the former forming a
thick rotten stone. These mark the base of the Downtonian and over the
next 50 metres is a development of very calcareous beds approaching an
actual limestone in composition. Continuing on; a small hiatus
intervenes due to faulting and then there is a quarry exposing well
bedded Downton Castle Sandstone; with small flecks of plant remains
visible on bedding planes. Following the track which has now turned SE;
the sandstone becomes more massive and then is succeeded by a hard
siltstone; which may represent overlying Temeside Shales although this
has not been confirmed. Overall section is 500 metres long and typically
2 to 3 metres high. |
Open access within a Forestry Commission area. By well made forest
tracks and foot-paths. Nearest parking is at Colstey on A488 Clun to
Bishop's Castle road |
LGS Yes. This section; with its easy accessibility; designated a LGS
as an exemplary example of the Silurian Ludlovian/Downtonian transition;
particularly rich in fossil and sedimentary features. |
Fossils and Sedimentology/Stratigraphy |
| 1051 |
SO 323 933 |
More Quarry
(older) |
Quarry (disused) |
Ordovician: Hope/Stapeley Beds of Llanvirn Series; intruded by dolerite
(?gabbro) |
|
Among the late Ordovician intrusions this area to the east of the More
Quarry was previously an SSSI (ref. 4). The site is a small quarry to
the west of the disused but dangerous main quarry. It is notable for the
extended contact feature showing a 150 mm chilled margin of the massive
coarsely crystalline dolerite(?gabbro) and hardened country rock. The
latter is Hope Shales and/or Stapeley Volcanics. There are suggestions
in ref(1) that the intrusion may be overlain by Silurian. Some variation
in the identity of intrusive rock variously described as gabbro;
dolerite or gabbroic dolerite (ref. 2); margins are chilled. No fossils
found; the area of the descheduled SSSI to the east of the main quarry
is described as fossiliferous Hope Shales (ref. 3). Massive intrusion of
indeterminate form; slickensides. Baking of country rock; chilling of
margins. |
Via A488 to point about 2 km N of Lydham. Limited parking on E side of
A488. |
LGS Yes. The site is designated a LGS as a good and well displayed
example of the features developed in the contact zones between a large
igneous intrusion and sedimentary country rocks. It also provides a
specific example of one a number of large basic intrusions which occur
in this area; notably the Laccolith of Corndon Hill and the Picrite of
Cwm Mawr. |
Mineralogy/Petrology |
| 1055 |
SO 375 942 |
Upper Gravenor - Wentnor |
Quarry (disused) |
Dolerite intrusion within Precambrian: Wentnor Series |
|
The quarry is excavated in a large linear intrusion of dolerite which
can be traced up the hill to the west for a distance of 0.5 km. The
intrusion cuts across the dip of the fine sediments of the Bridges Group
and is therefore probably a dyke (ref. 1) albeit quite thick. The quarry
has an unusual form having been excavated as an L-shaped cutting some 3
to 4 metres wide and up to 5 metres deep. The freshest rock is massive
fresh and crystalline and is exposed on the left wall of the excavation.
It appears to contain large 1 metre scale xenoliths of country rock
which are clearly baked to a black colour. Similar xenoliths appear in
the right wall but in the furthermost part of the ‘L’ this side shows
the dolerite in a different form. A a slope appears with many apparently
spheroidally weathering boulders irregularly disposed of different sizes
and not obviously related to any jointing pattern. The boulders are the
result of deep chemical weathering (possibly Tertiary in age). In other
parts there is developed curvi-linear columnar jointing chilled margins
and country rock xenoliths. |
From B4383; 2 km south of Bridges cross-roads; take a minor road SSW |
LGS Yes. The quarry designated a LGS as an exemplar of an intrusion;
both baking and incorporating xenoliths of country rock as well as
showing features of columnar jointing chilled margins and spheroidal
weathering. |
Mineralogy/Petrology |
| 1060 |
SO 391 874 |
Hillend (West
of Farm) |
Track/roadside |
Precambrian: Synalds Group of Longmyndian - Purple shales; Silurian:
Upper Llandovery; conglomerate and grit. |
Small exposure off road at base of hillside. |
The deposition of early Silurian strata on a block of Precambrian
sediments is known from a sequence of exposures between Plowden and
Little Stretton. Mapped in detail by Whittard (1932) who identified
features including sea-stacks beach deposits and pebble bars. The only
direct recognition of this work is a SSSI at Hillend where a quarry in
Pentamerus Beds is designated for its micro- and macro- fauna content
(ref. 5). This site (to the east of the SSSI) convincingly shows the
unconformity with Upper Llandovery age grits which are occasionally
fossiliferous resting with marked discordance on eroded purple shales of
the Synalds Group. Fossils rare in grits; brachiopods in higher beds.
Precambrian shales have vertical dip and strike NE; basal Silurian grits
dip ca. 25° S. Strong unconformity. |
Along A489 between Craven Arms and Lydham; ca. 300m. SW of Hillend
Cottage. |
LGS Yes. Designated as the predominant example of the unconformity
which lies at the base of the Silurian in Shropshire and the Borders. It
is of particular value since related exposures to the east allow the
demonstration of a complete stratigraphic column for strata within the
Silurian as far as the cut-off in Wenlock Shales by the Church Stretton
fault system. |
Structure and Sedimentology/Stratigraphy |
| 1084 |
SO 421 946 |
Ashes Hollow
-Little Stretton |
Natural exposure |
Precambrian: Longmyndian Group: Stretton Series; Stretton Shales; Burway;
Synalds and Portway Groups |
Incised Vee-shaped stream valley with overlapping spurs |
The valley from Little Stretton (SO441920) to Boiling Well (SO421946) is
about 4 km long. There are very many good exposures especially of Burway
Lightspout and Synalds Groups. Overall the best exposures (some 21 in
number) are fully described in an attached document ‘Precambrian
Stretton Series of Ashes Valley Longmynd’ which uses the format of a
Geological Itinerary to effect a description. Features covered include
crenulation and kink bands in the Stretton Shales brecciation and
quartz-filled tension gashes in the Buxton Rock Scree fans; freeze-thaw;
possible turbidites and lamination in the Burway Group; greywacke
sandstones of Cardingmill Grit; rippling; desiccation cracks; cleavage;
cleavage refraction and way-up criteria in Synalds Group; lithic tuff
and transverse faulting of vertical strata in Batch Volcanics; joint
planes; cut pebbles; slickensiding and fault location in Huckster
Conglomerate; cross bedding; erosional base and pick-up clasts in
Portway Group. Geological Summary (with keywords). Lithologies:
Indurated mudstones; siltstones; greywacke sandstones; conglomerate;
lithic tuffs and dolerite. Petrology: Greywacke; dolerite and volcanic
tuffs. Minerals: Quartz. Palaeontology: None. Structure: Steeply dipping
limb of a recumbent syncline (ref.1). Relationships: Conformable
sequence of differing lithologies. Palaeoenvironment: Upwards coarsening
sequence; possibly progradational through turbidite; delta; alluvial and
braided alluvial (ref.2). |
From A49 at Church Stretton travel 2 miles to Little Stretton and locate
the ‘camping field’ and ford. Open; mainly along public footpath; some
over heather clad slopes. 2 inns in Little Stretton; all other in Church
Stretton |
LGS Yes. Ashes Hollow streamway designated a LGS as a coherent upwards
coarsening sedimentary sequence through most of the Precambrian Stretton
Series. It displays a wide diversity of features and is well able to
support a geological itinerary. |
Structure and Sedimentology/Stratigraphy |
| 1106 |
SO 444 804 |
A49 Craven Arms
to Onibury |
Cutting (road/railway) |
Silurian: Lower Ludlow Shales to Upper Ludlow Shales |
|
South of Craven Arms the eastern side of the A49 cuts through a number
of spurs providing a sequence of exposures from Lower Ludlow Shales
through the Aymestry Group to Upper Ludlow Shales. Distances are given
in kilometres south from cross-roads in Craven Arms and (in brackets)
north from level crossing at Onibury. 2.53-2.73 (1.83-1.63) Lower Ludlow
Shales; 3.07-3.27 (1.39-1.19) Aymestry Limestone; much attenuated but
good transition to Upper Ludlow; 3.81-3.91 (0.55-0.45) Upper Ludlow
Shales; 4.02 (0.34) Upper Ludlow Shales in entrance to quarry. Exposures
are generally fossiliferous and dip gently to SE. Conformable sequence. |
South from Craven Arms; parking alongside A49 difficult; best to walk
sections starting from entrance to Park Farm SO406802 just south of
first section. Hazard of passing traffic is serious for groups |
LGS Yes. This section designated as a LGS to help ensure its survival
as a very visible section through that sequence of Shropshire's Silurian
strata which determine the topography of a large area of the county. |
Fossils and Sedimentology/Stratigraphy |
| 1109 |
SO 446 899 |
Chuney Pool - Acton Scott |
Bank |
Ordovician: Acton Scott Group below Limestone. |
|
Approaching along the outflow stream-way leading to Chuney Pool this
makes an abrupt left turn to reveal a small ravine with a water cascade
at the end. Both walls of the ravine expose olive-green micaceous
siltstone; dipping c. 20° N. This rock is soft and shows few brachiopod
casts and impressions. 2 faces each 20 m long and up to 4 m high. |
From A49 250 m south of Marshbrook garage (SO442898) take road
sign-posted to Acton Scott. Take foot path immediately behind black and
white cottage; after 50 m turn right and follow stream-way through
woodland. Parking at Marshbrook; Wayside Inn and cafe. Woodland partly
used for game birds; some felling. |
LGS Yes. Designated as the principal exposure of fossiliferous
sediments within the lower part of the Acton Scott Group. |
Fossils and Sedimentology/Stratigraphy |
| 1110 |
SO 446 914 |
Wiresytch Quarry - Church
Stretton |
Quarry (disused) |
Ordovician: Harnage Shales; Longmyndian: Wentnor Series |
Truncated spur - main valley glacier? |
The quarry has been excavated at the truncated end of a spur of
Precambrian sedimentary rocks (Wentnor Series). However with one small
exception the quarry faces are of Ordovician Harnage Shales. Due to
degradation and vegetation cover the best face is to the left (NW). This
shows flaky shales with occassional bands of a blocky nature. Bedding
appears horizontal but is towards the observer. There is much localised
distortion possibly due to the proximity of fault F1 of the Church
Stretton complex (200 m to W). Within the shales are harder lenses which
are fossiliferous and under the hand lens can show a wealth of fine
detail. The centre face is much covered with scree but at floor level in
the centre is a small block of reddish sandstone; much rotted. This
represents the Precambrian basement mapped as Wentnor Series. The actual
unconformable contact described in ref.1 as a pebbly sandstone is no
longer visible; presumably buried under an overburden of shale talus.
The right-hand face is totally obscurred by vegetation. 15 m high; faces
total 100 m. Rich fauna; somewhat delicate. Dip 20° S; bedding
distortions. Palaeoenvironment: Shoreline and subsidence. |
200 m east along track leaving A49 at SO444915 opposite Little Stretton.
Parking in lay-by on A49; Ask permission of occupants of Oakfields |
LGS Yes. The quarry designated a LGS as it clearly shows the nature of
the unconformity at the base of the Ordovician and for the specific
character of the fossils present in the Harnage Shales - currently the
subject of research by Professor W.Dean of Cardiff University. |
Structure and Sedimentology/Stratigraphy |
| 1112 |
SO 446 961 |
Batch Valley -
All Stretton |
Natural exposure |
Precambrian: Longmyndian: Synalds Group (Batch Volcanics). TYPE
LOCALITY: For the Batch Volcanics with the Synalds Group |
|
Four ash bands have been identified within the predominantly purple
shales of the Synalds Group. They outcrop across the ridge which rises
westward from the junction of Johnathan's Hollow and Long Batch; the
lowest band also outcrops continuously along the ridge rising NE from
the same junction. In this latter situation the outcrop well shows the
numerous small transform faults (both dextral and sinistral) which
affect the outcrop of the steeply dipping Longmyndian sediments. As part
of this survey the position of the outcrops of the 4 bands along the
western ridge has been remeasured. The bands are individually described
in the table taken from ref.1. Band A (the Andesitic Ash) forms the
lower part of the second rock step at the start of the ridge. Only the
purple facies is visible; the green variant being turf covered. As the
dip is steep to the NW the outcrop cannot be traced further to the west.
The ridge has a trend of 300° and an average slope of about 30°.
Ascending its crest band B occurs after 233 ft. (1 foot = 0.30 metres)
and band C after 294 ft. just above the second of a pair of small trees.
Band D outcrops after 401 ft. and the base of the Lightspout Group
occurs after 464 ft. where the angle of the ridge eases somewhat and
crags become much less frequent. Band C (the White Ash) can be traced
westward across the face of the hill as far as the entrance to Long
Batch. The NE ridge has a trend of about 45° and along it band A (the
purple Andesitic Ash) can be traced for about 150 m. Between the 4 ash
bands the purple shales often show a polished fluting decorated with
arrays of fine pits which have been ascribed to rain spots. |
From All Stretton tarmac road leads past Village Hall to car park after
400 m. Thereafter a track continues 800 m to Johnathan's Hollow. The
Long Mynd has open access. Shop Pub and Hotel in All Stretton. |
LGS Yes. Type Section for the Longmyndian Batch Volcanics; illustrates
the geometric relations encountered in mapping dipping strata in a hilly
environment and for the demonstration of volcanic activity within
Longmyndian times. |
Sedimentology/Stratigraphy |
| 1119 |
SO 450 895 |
Acton Scott (W
of Church) |
Quarry (disused) |
Ordovician: Acton Scott Group; Limestone member |
|
The quarry lies on the south slope of a low hill of more resistant
strata. This is in fact the Acton Scott Limestone; a local feature of
the Ordovician succession hereabouts. Quarry sections show gently
dipping bedding of fine pale yellow sandstones and siltstone succeeded
by ‘limestone’. The best section is in the centre of the main face. Here
are massive creamy sandstones of thickness 50-300 mm separated by 25 mm
soft pale mudstone partings. However ‘limestone’ is something of a
misnomer since no specimen of the rock in this quarry effervesced with
hydrochloric acid and its porosity and absence of shell material
suggests that it is here a de-calcified sandstone. Fossil material is
abundant on bedding planes both within the massive material and at the
partings in a 5 m thickness of fine calcareous sandstone. Brachiopod
impressions are common on bedding planes. |
Public footpath from Church Farm to Marshbrook; quarry lies in woodland
area 500 m WNW of Church Farm. Large car-park opposite Acton Scott
church. Access permission required. |
LGS Yes. The quarry designated as a LGS as the only sizable fossiliferous exposure of the Acton Scott Limestone. |
Fossils and Sedimentology/Stratigraphy |
| 1120 |
SO 451 907 |
The Hough (S) streamway -
Acton Scott |
Stream/brook |
Ordovician: Cheney Longville Flags and Acton Scott Group. TYPE LOCALITY:
Ordovician: Actonian: Ragdon Member |
|
Exposures of the soft sedimentary rocks in this area are scarce and
generally confined to streams. Thus this stream south of the Hough has
been chosen in ref.1 as the stratotype for the boundary between the
Cheney Longville Formation and the overlying Acton Scott Formation. It
is also gives the standard section defining the Ragdon Member of the
Acton Scott Formation which also includes the overlying Wistanstow and
Henley Members. Proceeding upstream from the stile (see ‘Approach’) the
first exposure is a small outcrop of the Wistanstow Member below a
cluster of holly trees; it is then about 100 m to where the stream-way
becomes more ravine-like. The eastern face shows an almost continuous
section in soft buff siltstone. This is bioturbated and so lacks regular
bedding planes. It has a rich and diverse fauna and dips to the south so
that the sequence descends to the north. In 200 m the ravine begins to
open out and a harder flaggy rock with tentaculites appears before the
streamway finally emerges onto an open field just short of the road. 200
m long and on average 1 m high; 2 m with excavation. Rich fauna. Dip 20°
S. |
From the road-side 400 m south of The Hough a public footpath heading SW
crosses diagonally over a field to cross a stream and stile after c. 250
m. Exposures are upstream of this point. There is no public right of
way along the stream. Limited road-side parking. |
LGS Yes. The site designated as a LGS in order to confer some
protection on a significant but fragile stratatype section. |
Sedimentology/Stratigraphy |
| 1122 |
SO 451 935 |
Cunnery Terrace |
Track/roadside |
Precambrian: Longmyndian: Stretton Shales |
|
These exposures of Stretton Shales are described (ref.1) as showing
thrusting minor folding kink-band and cleavage development. Thrusting is
implicit in a near horizontal disturbed zone with intense crumpling of
the grey shales. Explicit features are clear kink-bands associated with
joint movement slaty cleavage and cleavage refraction. At the furthest
point is a dolerite intrusion; its contact with the shales (reportedly
faulted) is currently visible alongside the steps ascending to ‘Greenmount’.
It shows a vertical plug of rotted brown dolerite with vertical faults
seperating from surrounding shales which have suffered even further
distortions. Proceeding along Cunnery Terrace exposures are found on the
RH side (W) in front of ‘Westville’ (rockery); driveway to ‘Fourways’
and in front of ‘Green Mount’ and in front of ‘Trefnant’ (further
dolerite). 3 sections; up to 2 m high and respectively 10 m; 40 m and 3
m long. No fauna. Distortions of ‘incompetent’ beds. Palaeoenvironment:
Deep water; turbidite sequences. |
From Church proceed south along Church Road turning right into Cunnery
Terrace; exposures begin after the sharp LH bend at 200 m. Have respect
for private gardens. |
LGS Yes. Shows thrusting and minor folding kink-bands and cleavage
development |
Structure |
| 1128 |
SO 459 955 |
Buxton Quarry -
All Stretton |
Quarry (disused) |
Precambrian: Stretton Series: Stretton Shale Group; Buxton Rock; Burway
Group. TYPE LOCALITY: Buxton Rock |
|
Mapping of the sequence of Longmyndian sediments has required use of
disitinctive and persistent beds to act as ‘markers’. A siliceous tuff
(green-grey and cherty in appearance) has been used to define the base
of a more arenaceous and flaggy Burway Group over lower and generally
incompetent Stretton Shales. Buxton Quarry provides the type section.
The RHS is dominated by a vertical bedding plane is Stretton Shales (a
rock of weakly bedded and monotonous grey mudstone/fine siltstone).
Occasional paler bands up to 10 mm thick may mark the presence of
volcanic ash fall-outs. The main outcrop of Buxton Rock is in the centre
where a rough track ascends steeply to higher levels. The Buxton Rock is
recognised by its cherty texture an absence of internal bedding or
lamination and with a slightly undulose form. It can be seen to split by
shaly horizons into separate units of variable thickness and at least 8
such beds between 200 and 500 mm thick can be identified. The rock has
been described as a ‘silico-felspathic slate in concretionary layers’
(ref 4) and as a ‘silicified dust tuff’ (refs 2;3;4). To the left and
in the higher parts rocks of the basal Burway Group are seen (notably
flaggy bedded with units thickness 50 to 150 mm seperated by thin shale
horizons). Slight grading can be detected suggesting younging to the
left (W). Thin pale bands 2-3 mm similar to those seen in the Stretton
Shales are also present. Quarry is roughly L-shaped; 30 m across long
base; 20 m across short and up to 25 m high. Silification and quartz
veining. No fossils. Near vertical dipping sequence; strike SW-NE;
younging to NW. East part of quarry shows very large bedding plane and
similar outcrops are found in a lane just to the west. |
In
All Stretton take lane sign posted to 'Village Hall'; Quarry is on right
after 200 metres. Ample parking and shop/pub/hotel in All Stretton. |
LGS Yes. Buxton Quarry designated a LGS as the Type Section for the
Buxton Rock; this is a marker horizon for the boundary between lithologically changing rocks of the Stretton Shale Group and the Burway
Group within the Precambrian of the Longmynd. |
Sedimentology/Stratigraphy |
| 1135 |
SO 468 821 |
Bache |
Quarry (disused) |
Silurian: Upper Ludlow Shales |
Fault scarp |
Quarry lies on a SW facing scarp slope due to the down-throw of the
strong SE trending Bache Fault. The quarry face shows an alternation of
massive siltstone with some current bedding and bands of vertically
jointed calcareous sandstone up to several inches thick. The main
feature is however a 0.7 m thick bed showing a text-book example of
slumping. This strongly resembles a similar feature in the Whitcliffe
quarry type section for the Whitcliffe Stage (ref.3). There are also
some lenses of fossil shells now leached to a ‘rotten-stone’. Face is 30
m long and 4 m high. Brachiopod casts & shells. Gentle dip; modest
jointing with conspicuous slumping. |
From Bache House on minor road between Greenway Cross on B4368 and
Burley take public footpath heading SE towards lake; quarry is situated
where this path crosses a tarmac drive. Limited parking; other in Craven
Arms 2 miles distant. |
LGS Yes. This site displays a ‘text-book’ example of slump bedding and
is situated on a fault scarp. |
Sedimentology/Stratigraphy |
| 1144 |
SO 473 958 |
Botvyle Quarry |
Quarry (disused) |
Silurian: Lower Ludlow Shales and Aymestry Group. |
Strata emplaced by effect of strong fault. |
The quarry lies in a tree-covered spur some 200 m SW of the start of the
access drive to ‘Botvyle Barn’. As this drive begins to ascend the spur
Lower Ludlow Shale strata are exposed in the left hand bank; better
described as flaggy green/grey mudstones these beds progressively change
to a nodular limestone which is the main facies of the Aymestry Group
beds exposed in the quarry. Typically massive beds up to 3 m thick are
separated by grey calcareous mudstone parting of 25-50 mm thickness.
These show flute casts and fossil impressions. The limestone nodules
weather out to fist-sized cobbles which are usually very fossiliferous;
mainly brachiopod shells and casts with much comminuted debris. The
whole dips SSE at a high angle 70-80° but without other effects that may
have been expected from the proximity of the major Church Stretton Fault
F1. Brachiopoda dominant; occasional gastropod; crinoid; bryozoan.
Graptolite Monograptus leintwardinensis reported locally ref.(2).
Palaeoenvironment: High energy? |
Cross-roads c. 2 miles north of traffic lights at Church Stretton on
A49. At this point take lane to SE sign-posted to Cardington; after 200
m road makes sharp turn to left and a name-plate marks start of access
drive to ‘Botvyle Barn’. (Lower Botvyle Farm is further 250 m along
road). Parking on A49 verge. Access permission from Lower Botvyle Farm. |
LGS Yes. This site comprises the most northerly emplacement of an
outlier of Aymestry Group strata |
Fossils and Sedimentology/Stratigraphy |
| 1145 |
SO 474 924 |
Hope Bowdler |
Track/roadside |
Ordovician: Harnage Shales. |
|
By
the footpath sign beneath a tree is a small patch of soft brown shale
fragments identified as Harnage Shales. By the gate is what looks like a
small outcrop of hard volcanic rock; if so this would represent the
Harnage/Uriconian unconformity without the development of a
conglomerate. Following the footpath over the stile to the right; the
path enters a sunken way; there is another small outcrop of Harnage
Shales 30 m on the left. Shales are totally fragmented; no in situ
exposure. |
150 m south along the Ticklerton road from Hope Bowdler there is a
footpath sign on the RHS (W). Parking in Hope Bowdler |
LGS Yes. Designation as a major unconformity of Ordovician Harnage
Shales laid down upon a weathered surface of Precambrian Uriconian
Volcanics. The former yields a shelly fauna and significant ostracodes
have been found. |
Sedimentology/Stratigraphy |
| 1149 |
SO 475 947 |
Willstone Road
Quarry |
Quarry (disused) |
Cambrian conformable junction between dipping Lower Comley Sandstone and
Wrekin Quartzite |
Relative erosion rate of volcanic (rhyolites; tuffs; intrusives) and
unmetamorphosed sediments. |
The ‘quarry’ is now a vertical bank; some 1 m high and 10 m long
bordering a farm-track. To the right are ca. 8 m of buff-coloured
fine-grained sandstone (Lower Comley) whilst to the left are ca. 3 m of
grey/white quartzite (Wrekin Quartzite). The junction between is
clearly conformable and strikes due north with a dip 70° E. Both rock
types are undistorted and only moderately jointed. Uriconian volcanics
outcrop on the hillside to the W and fault F2 is mapped immediately to
the NW cutting off the quartzite outcrop. Cursory examination has failed
to reveal any fossils. |
By
foot or bike along old road between Willstone Farms (SO491953) and
Eastwood; Church Stretton (SO464940). From Willstone; 500 metres beyond
Cwms Cottage this road makes a left turn from where a public footpath to
Caer Caradoc strikes off to the right (N). Taking this path the site is
immediately seen some 50 m to the right (E). From Church Stretton the
same point is reached some 700 m beyond the defile between Helmeth and
Caradoc Hills. |
LGS Yes. Conformable junction between the Lower Comley and the Wrekin
Quartzite |
Fossils and Sedimentology/Stratigraphy |
| 1150 |
SO 475 951 |
Caer Caradoc
Ridge |
Natural exposure |
Precambrian: Uriconian: Ragleth Tuffs; intruded by a dolerite sill. |
Scarp feature |
200 metres SW of the summit is a low col to either side of which
outcrops a strong linear feature. This is a well-bedded acidic tuff
showing small scale current bedding features. Traced down the hillsides
to NW or S it is seen to be underlain and intruded into by a dolerite.
Near the ‘col’ the outcrop appears finely bedded; weathers to resemble
the summit rhyolites in colour and surface texture; however the
‘bedding’ is much more genuine with beds varying in thickness and grain
size and bedding planes lacking slickensiding. Interpreted therefore as
a bedded acidic tuff; the dip is to the west around 45°. In detail the
bedding shows grading; small folds; closely spaced jointing and features
suggestive of slumping and/or de-watering. This is best displayed 60 m
south of the col. Before that (at 45 m and 55 m) the tuffs can be seen
to be underlain by and intruded into by a dark grey rock identified as
dolerite. At 100 m there is clear emergence of this underlying dolerite
forming a sill-like contact with the overlying tuffs which is displaced
up-slope by a small fault to expose the lower contact. Generally 2 m
high extending 200 m to S and 200 m to NW. Structure: Tuffs dip west
around 45° and in absence of significant transverse faults form a
remarkable linear scarp feature. This linearity may be due to a NW-SE
trending fault which separates Ragleth Tuffs from Caer Caradoc Andesites
and has itself been intruded with dolerite (ref.1). |
From summit walk SW 200 metres to a low col. |
LGS Yes. Well bedded acidic tuff |
Mineralogy/Petrology |
| 1158 |
SO 477 953 |
Caer Caradoc |
Natural exposure |
Precambrian: Uriconian: Caer Caradoc Rhyolite and an Andesitic lava.
TYPE LOCALITY: Caer Caradoc Rhyolite; Caer Caradoc Andesite. |
Differential erosion of hard resistant rocks of Precambrian basement
produced by uplift as a horst. Possible nunatak. |
The summit of Caer Caradoc within the confines of the Iron Age Hill Fort
provides splendid outcrops of rhyolites; variously flow-banded;
amygoidal; brecciated and slickensided. An area of andesite (sometimes
amygdaloidal) and a small intrusion of dolerite can also be recognised
appearing to underlie the rhyolites. The best approach is via the NE
ridge where the change on crossing the fort embankment; from dark grey
Little Caradoc Basalts to large pink and yellow crags of Caer Caradoc
Rhyolite is quite dramatic. At this NE end the exposures display an
apparent bedding albeit much contorted twisted and over-turned. On
examination the ‘bedding planes’ are generally slickensided and the
‘bedding’ seems more a consequence of the flow of viscous acid lavas.
Exposures in the actual summit area are generally massive irregularly
jointed and sometimes vesicular. Brecciation of the flows becomes more
conspicous as the rhyolite forms ‘ramparts’ to the hill fort on the SE
side. A zone of vertical banding intervenes before the ‘gateway’
dominated by a large high block of brecciated material. At this point
emerging from beneath the greensward are blocks of fossiliferous
Chatwall Sandstone and Quartzite has also been built into the
embankment. Just west of the ‘gateway’ are exposures of vesicular Caer
Caradoc Andesites which reinforce the impression that the rhyolite forms
a comparatively thin bed. Further exposures continue to the south
reaching almost to the foot of the steep hillside. No fauna within
volcanics but Ordovician fauna in ‘erratics’. Structure: Base of
rhyolite flow dips towards SW; Caer Caradoc hill is delineated by strong
NE-SW faults and this directional trend can be seen continuing to the NE
to encompass Lawley Hill and the Wrekin. The area of Caer Caradoc is
some 120 hectares in extent; involves 8 individual stratigraphic rock
units and at least 50 individual exposure sites. This was fully surveyed
over the course of several days of late Aug and Sep 2001. In view of the
large amount of data collected it is convenient to use this
‘description’ field to record what may be regarded as the features of
most interest and significance and to append methodology; detail and
conclusion as attachments to this report. Principal features: (1) many
exposures of igneous fine-grained acid and basic rocks; instrusives and
lavas; together with fine grained bedded tuffs. (2) a major
unconformity whereby the Cambrian Wrekin Quartzite overlies a sub-set of
the volcanics. (3) major exposures of rhyolites showing various degrees
of auto-brecciation; slickensiding; flow banding and elongated vesicules.
(4) a folded syncline in bedded tuffs with sufficient exposure to allow
dip measurements which confirm that the syncline plunges NW. (5)
visible evidence of doleritic intrusion in the sense of chilled margins
and injection into open joints. (6) a major and very visible normal
fault which crosses the axis of the hill suffering change of direction
of its surface outcrop. (7) other faults classified as reverse or
thrust; in particular exposure of a possible thrust plane. (8)
significant amounts of sedimentary erratics; Cambrian and Ordovician
associated with the hill fort on the summit. |
Footpaths converge on summit from many directions. The footpath up the
NE ridge is not a public right of way. |
LGS Yes. Exemplar for Precambrian volcanics. Wealth of other geological
features; high scores in all the assessment criteria and scope for a
geological itinerary or trail. Education - scope for field examination
of wealth of features and for practical exercises. Scientific - nothing
seems to have been published since the Geological Survey Memoir (Greig
et al 1968). Some unresolved problems remain; so a possible area for
research. Historic - a notable Iron Age Hill Fort with an intriguing
geological problem. Aesthetic - superb view points through 360 degrees. |
Mineralogy/Petrology |
| 1172 |
SO 483 955 |
Robins Tump |
Natural exposure |
Cambrian: Lower and Upper Comley Sandstones and Grits |
Situated in an area of fault-bound blocks in which exposures are few but
differential erosion rates allow for feature mapping. |
The summit of this small but conspicuous hillock shows Upper Comley
Grits dipping east with Lower Comley Sandstones beneath. The Comley
Limestones (which bridge this junction in the Comley Quarry (SO484965))
are absent. It is the site of one of the many excavations carried out by
E.S. Cobbold in the course of his elucidation of the stratigraphy of the
local complex faulted area. Other excavations were made on the ‘saddle’
to the south and several near the stream at the foot of the northern
slope where Lower Comley strata are better exposed. No fossils found -
may have been picked clean. An unconformity seperates Lower and Upper
Comley strata but this can only be deduced from the exposures; not seen. |
By
paths from the track between Willstone Farm and Cwms Cottage or by paths
from Comley via Hill House. |
LGS Yes. Designated as a LGS as the only exposure of the junction
between Lower and Upper Comley strata and as tribute to the work of the
geologist E.S. Cobbold |
Sedimentology/Stratigraphy |
| 1190 |
SO 495 851 |
The Sun Inn (car park) -
Diddlebury |
Cutting (road/railway) |
Silurian: Upper Ludlow Shales |
|
Although mapped as Downton Castle Sandstone it is believed that the
section exposed in the lower part of the bank on the north side of the
carpark is in fact Upper Ludlow Shales. This shows blocky buff and
yellow silstones with some false bedding current bedding and slumping
visible. There is a sparse shelly fauna. Higher up the beds become more
friable but cannot be directly observed due to a heavy over-growth of
vegetation. The Ludlow Bone Bed could be expected at this horizon but
was not identified. 50 m long and 2 m high. Brachiopods. |
Car park of the Sun Inn on B4368 about 5 miles from Craven Arms. Parking
and refreshment! |
LGS Yes. A large and very accessible site which has potential to show
the Ludlow Bone Bed. False bedding and current bedding and slumping
visible. |
Sedimentology/Stratigraphy |
| 1192 |
SO 495 862 |
Delbury Quarry |
Quarry (working) |
Silurian: Aymestry Group to Upper Ludlow Shales; Silurian: Upper
Leintwardine to Lower Whitcliffe |
|
Site of working quarry excavating local building stone. Quarry is a
crude excavation by backactor into side of hill bordering an old quarry
(old faces of which remain). The location is mapped as Upper Ludlow
Shales but is probably transitional between Aymestry Group and Upper
Ludlow. Rock is generally flaggy and variable between siltstone and grey
shelly limestone which weathers to pale brown. This has an abundant
fauna notably including many gastropods encrusted with bryozoa in
symbiotic relationship (ref.3). Low down in the sequence are
honey-combed joint faces; well-weathered and contain a persistent bed
with excellent small-scale slump or de-watering structures. This face
resembles the honey-combed Upper Leintwardine below the base for the
Whitcliffian stage in the standard section at Dinham in Ludlow (ref.2).
Above are thin micaceous sandstone layers which would correspond to
Lower Whitcliffe and contain bedding planes densely packed with fossil
assemblages. New excavation is 40 m long by 5 m high. Rich shelly fauna
with brachiopods and gastropods. Dip 5° SE. Old delve to NE. |
On
B4368 at Diddlebury take lane heading north signposted Pinstones; quarry
is signed on RHS after 800 m. Private ground. Limited parking |
LGS Yes. To ensure preservation of features at the transition between Aymestry Group and Upper Ludlow Shales (Upper Leintwardine to Lower
Whitcliffe). |
Fossils and Sedimentology/Stratigraphy |
| 1199 |
SO 503 858 |
Bache Mill Lane |
Cutting (road/railway) |
Silurian: Upper Ludlow Shales and Downton Castle Sandstone |
|
Exposure comprises a sequence of roadside cuttings and small roadside
quarries on both sides of the narrow lane leading from the B4368 at
Diddlebury to Bache Mill and Middlehope. The section begins with a
rather fragile garden wall in Downton Castle Sandstone which is then
succeeded by a constant horizon in Upper Ludlow Shales as the lane
ascends the dip-slope. These are of calcareous siltstones. The Bone Bed
does not appear to be present or visible. Up to 2 m high over length of
300 to 400 m. SE-facing dip slope; conformable. |
Lane heading N from Craven Arms/Bridgnorth road at Diddlebury. Parking
on roadside verge just north of lane junction. Traffic hazard in narrow
lane but visibility good |
LGS Yes. Accessible exposure of Downton Castle Sandstone succeeded by
Upper Ludlow Shales. |
Sedimentology/Stratigraphy |
| 1205 |
SO 511 806 |
The Patch -
Titterhill |
Quarry (disused) |
Devonian: Psammosteus Limestone with beds above and below |
Quarry lies at top of steep scarp; scarp slope appears to be
predominantly marls and thin sandstones |
The quarry lies in trees immediately behind the ‘Unsuitable for Motors’
sign. On the right hand side the quarry face presents a single wall 1.5
metres high comprising a calcareous red-purple sandstone (or a sandy
limestone). This bed dips gently to the left and to the left an
embayment shows a further development. The calcareous sandstone has an
erosional top and is overlain by 0.5 metres of cobble sized pieces of a
rubbly limestone embedded in an irregular mixture of bedded sandstone
and reddish marl. This in turn is succeeded by 0.2 metres of highly
calcareous conrstone - here considered to be a bed of Psammosteus
Limestone. Above this is 0.5 metres of massive olive sandstone which is
current bedded at its base. The quarry is not specifically mentioned in
ref.1 which however does describe the local occurences of Psammosteus
Limestone. The roadside exposure at SO510807 at the foot of the scarp is
now degraded. RHS wall is 5 m long and 1.5 m high. Embayment is 3 m wide
and 3 m high. No fauna found. Dip 5° SE. |
Best approach is from Highcroft along lane signposted Titterhill and
Thriftwicket lane; ascent or descent of scarp by motor vehicle needs
extreme care and is not recommended. Limited parking and turning space
at site |
LGS Yes. The site represents the only exposure of Psammosteus Limestone
in the area. Pending the discovery of better exposures it should be
designated a LGS since this limestone marks the important boundary
between Silurian and Devonian strata. |
Sedimentology/Stratigraphy |
| 1213 |
SO 573 880 (537 880 on GIS) |
Lower Earnstrey
(stream-way) - Abdon |
Stream/brook |
Devonian: Ditton Series |
|
The stream channel (which may be dry in summer) provides a long section
through the characteristic rocks of the Ditton Series. The stream bed
lies mainly upon sandstone bedding planes; the banks are frequently cut
into red and green marls; cornstones are common. The stream cuts down
through the sequence so that about a 10 m thickness can be examined in
detail. At least one fault shows contorted marl juxtaposed to massive
sandstone. Diamond pattern jointing ripple marking and current bedding
present within the sandstones. Downstream is the SSSI of Oak Dingle from
which fish remains have been collected; a similar possibility may hold
for this section. About 400 m long; banks up to 3 m high. |
From Tugford take the unsigned road at SO557872 heading NE towards
Earnstrey Hall and farms. Section is on LHS (north) after 1 mile. Access
requires crossing a barbed wire fence. Parking on verge only. |
LGS Yes. Location designated as a LGS as it is a rare open section in Dittonian strata showing the repeated deposition of units of thick red
marl sandstone and cornstone with associated sedimentary features of
ripple marking and current bedding. |
Sedimentology/Stratigraphy |
| 1215 |
SO 586 851 |
Cockshutford Stream - Abdon |
Stream/brook |
Devonian: Clee Group of sandstones. TYPE LOCALITY: Upper Devonian Clee
Group |
|
This stream-way ascends the western slopes of Brown Clee and provides a
complete 1 km section through the yellow sandstones marls and
occassional conglomerate of the Clee Group. No fossils recorded in
ref(1). Gentle dips to SE; some large scale current bedding acc. to
ref(1). |
Via minor roads on SE side of Corvedale to road-end at Cockshutford
SO580850. Then follow tarmac road through 2 gates and then for ca. 500m;
then head NW down through bracken to approach stream where follow path
of sorts until (past an old chapel on the right (S)) a grass ramp leads
down to stream-way itself at start of section. Ample vehicle parking at
road-end; nearest cafe etc. at Ditton Prior ca. 7 km |
LGS Yes. This is the type section for the Devonian Clee Group with a
complete section through marls sandstones and conglomerates between
Abdon Limestones and the Coal Measures of Brown Clee. |
Sedimentology/Stratigraphy |
| 1216 |
SO 593 843 |
Clee Burf - Burwarton |
Quarry (disused) |
As
mapped; Dolerite is always above Coal Measures. |
|
Sandstones of the Clee Group are succeeded by Coal Measures which in
turn are intruded by dolerite such as occurs at Titterstone. The
resultant outcrops are clearly displayed on the summit plateau of Clee
Burf at 1800' AOD. The area includes many bell-pits and quarried
dolerite in all stages of weathering as well as abundant Coal Measures
spoil. General dips are to SE; dolerite upper surface shows slight
chilling. |
Footpaths from all directions to summit of Clee Burf. Ditton Priors:
parking; cafe; Inn. |
LGS Yes. The hill top area of open pits and quarry designated as a LGS
since it comprises a unique combination of the highest coal workings in
the UK with ‘bell pits’ sunk through a dolerite capping to coal seams
below; plus features of an igneous intrusion displayed within the
quarried area. |
Sedimentology/Stratigraphy |
| 1217 |
SO 596 778 |
Radar Quarry
(formerly East Quarry) - Titterstone Clee |
Quarry (disused) |
There is no BGS 1:50 000 Memoir covering this area. Dolerite (probably
Upper Carboniferous) intruded into Carboniferous Coal Measures |
|
The very large quarry (now known as Radar Quarry; previously East
Quarry) and landscaped area immediately below (south of) the radar domes
on the summit of Titterstone Clee exposes many large buttresses of fresh
and weathered dolerite (locally known as ‘Dhu Stone’). Rock falls have
occurred here and the faces should not be approached closely. |
|
LGS Yes. This quarried industrial landscaped area is one of the most
easily accessible and impressive exposures of the Clee Hills dolerite
intrusions extraction of which so dominates the local landscape
community and economy. |
Mineralogy/Petrology |
| 1220 |
SO 631 928 |
Hudwick Dingle |
Stream/brook |
Devonian: Ditton Series just above Psammosteus Limestone. |
|
The base of the Devonian in Shropshire is taken at the Psammosteus
Limestone which caps the scarp along the SE margin of Corvedale. Many
streams have cut down through this scarp and provide sections notable
for fish remains; particularly in the beds or lenses of cornstone.
Hudwick Dingle (south of Monkhopton) is a good example. An ex-SSSI it
gives a long section through Ditton strata immediately above the
Psammosteus Limestone. It is notable for the many species of fish (at
least 12) identified there between 1869 and 1961. As the stream way
tends to flow over sandstone and cornstone bedding planes sections in
such beds are plentiful. Fish remains reported. Very gentle dip to S or
SE. |
From Monkhopton village take lane heading south towards Neenton. Climb
steeply and when clear of woodland turn left onto unsurfaced track.
Follow this past a house until dingle can be seen on left. Go down to a
wicker gate which gives access to the stream just above a 6 m waterfall.
Follow up-stream as far as track crossing; about 1000 m. Permission
needed - from where unknown. Limited parking in Monhopton; nearest pub
at Morville c.4 km. |
LGS Yes. This site shows the features typical of the ‘dingles’ which
drain the slopes around Brown Clee Hill. In addition it is also notable
for the many species of Devonian fish identified from fossil remains
collected here. |
Fossils and Sedimentology/Stratigraphy |
| 1223 |
SO 651 807 |
Oreton Quarry |
Quarry (disused) |
Carboniferous Limestone of upper part Z zone |
Quarries close to the top of a ridge. |
The small Carboniferous Limestone outcrop northeast of Titterstone Clee
was vigorously exploited in the late 19th Century. The beds bear
comparison with Carboniferous Limestone in other parts of the country
and include an ornamental stone - the ‘Clee Hill Marble’. The old
workings are fast succumbing to ‘landscaping’ and vegetation so that
only this one quarry still reveals any wealth of features. This was the
source of the building stone for St Peters Roman Catholic church in
Henley Road Ludlow (1935). The section includes 2 m massive limestone;
1.5 m calcareous shale and 9 m massive oolitic limestone with a limited
fauna. Weathering is now beginning to reveal depositional features.
Brachiopods corals and fish spines reported but rare. Gentle dip to SW.
Some good faces of limestone exposed here. At the base is a slab-like
layer above which is a 0.5 m thick horizon followed by one 2.5 m thick.
Detail of limestone faces is obscured by weathering; some chemical
solution. Although yellow on the surface the fresh limestone is grey and
coarsely crystalline. Evidence of slickensiding suggests faulting.
Height is approx. 6 m with more blocky limestone forming an overhang at
the top. In the NW corner of the wooded area there are lower but more
accessible faces. The limestone here is more thinly and unevenly
stratified (being coarsely crystalline); crinoidal and packed with small
comminuted fossil fragments. Dip is about 15° SE. Fallen blocks with
spiriferids were seen nearby. A game-keeper spoke of a fossil band in
the adjacent field noticed by the farmer when ploughing. Along the
public footpath to Farlow occur loose blocks of ORS conglomerate of the
Farlow Series. |
Network of minor roads; best method is to locate New Inn as only local
public house and marked on OS map. From Upper House on road between Well
Farm and Prescot take steep lane heading south. Seek access permission
from Mr Derricott of Middle House Farm (next to Upper House Farm) or
from occupants of ‘Liverpool Cottage’. Ample road-side parking; New Inn
is adjacent |
LGS Yes. This site is the only accessible major exposure in
Carboniferous Limestone in the southern part of Shropshire. This is a
rare example of Tournaisian age Carboniferous Limestone in this area.
The presence of the K and Z zone faunas at Oreton was first recognised
by Vaughan and recorded in his classic paper on Carboniferous Limestone
of the SW Province in 1905. |
Sedimentology/Stratigraphy |
| 1233 |
SO 738 907 |
Quatford Church - Quatt
Malvern |
Quarry (disused) |
Triassic: Lower Mottled Sandstone (ref.2); or Permian: Bridgnorth
Sandstone (ref.1) |
Isolated sandstone cliff in the Severn Valley; next to Quatford Church. |
A
25 m roadside section can be examined from the pavement. Here the major
feature in red sandstone is a single trough bedded unit resting on and
overlain by planar cross bedded units. The trough bedding shows
tangential cross bedding inclined up to 10° and has something of the
appearence of a wash-out channel. However ref.1 interprets this as a N-S
section through west-migrating barchanoid bedforms with large crescentic
slip faces moving under the influence of a long term easterly palaeowind.
South of the section is an irregularly quarried area where outcrops
display planar bedforms in three dimensions of maximum inclination 15°
where the sandstone is graded in parts. Soft patches of sandstone are
apparently uncemented. Road section is 25 m long and 4 m high; other
sections up to 2 m high. No fauna found. Palaeoenvironment: Dry sand
desert with easterly palaeowind. Between the church and the road is an
L-shaped section in reddish sandstone which gives an overall view of a
planar cross-bedded unit. The cross-bedding can be seen on different
scales from 200 mm down to millimetre scale. Texture is that of a
well-sorted medium sandstone with millet seed grains and little cement
or matrix. This suggests an aeolian origin. There are many insect
borings in the rock (probably solitary wasps) which indicates how soft
it is. It is therefore surprising how this Permian Bridgnorth Sandstone
stands up as vertical cliff faces (pore suction and grain interlocking -
locked sands). Moving towards the road it was noted how the changed
angle of dip around the L-shaped exposure gives a 3-dimensional
perspective from which the true direction and angle of the local dip can
be calculated. Along the pavement towards Bridgnorth is a single
trough-bedded unit on both sides of the road. Orientation is east-west
and the curved bedding is seen to wedge out as it approaches the
horizontal base. This unit can be considered as a cross-section of a
small barchan dune moving east-west. |
On
A454 3 km south of Bridgnorth in Kidderminster direction. Large layby on
east side of road; eating places 0.5 km further south. |
LGS Yes. An excellent example of a single trough-bedded sandstone unit
interpreted as a section of a barchanoid dune form perpendicular to its
direction of travel. The upstanding block near the church entrance
provides clear illustration in 3 dimensions of cross-bedded units. |
Sedimentology/Stratigraphy |
| 1236 |
SO 794 941 |
Claverley Road
Cutting (N) |
Cutting (road/railway) |
Lower Triassic: Wildmoor Sandstone Formation (`Upper Mottled
Sandstone'). |
|
An
extensive exposure of bright red Triassic sandstone that shows elaborate
and extensive sedimentary structures. Designated an SSSI; the section
shows a variety of sedimentary structures including flat bedding;
planar-; tubular- and trough- cross-bedding. 150 metres long by 10
metres deep following the path of the road. The extensive and great
variety of sedimentary structures in this Lower Triassic sandstone
indicate that deposition occurred in a sandy alluvial system with the
river flowing towards the north-west. Some horizons within the sands may
have been deposited as a result of wind action and it is therefore an
important site for the study of Triassic environments. |
Take the A454 Wolverhampton Road out of Bridgnorth. After about a
couple of miles there is a turning on the right hand side of the road
situated between a garage and the Wheel o Worfield Public House. Turn
right here signposted Claverley. Follow this narrow country lane for
about two miles until reaching a `T' junction. On the right the village
of Claverley and the church may be seen - turn left towards Shipley and
after some 200 m the road passes through a deep but narrow cutting which
is the exposure. Access is good. However; this is a deep but narrow
cutting on a single track country lane with no passing places and as
such passing traffic may prove a danger to the visitor. |
LGS Yes. The site designated a LGS as an exemplary exposure in aeolian
Triassic Sandstones with a wealth of sedimentary detail. |
Sedimentology/Stratigraphy |
| 1237 |
SO 794 940 |
Claverley Road
Cutting (S) |
Cutting (road/railway) |
Lower Triassic: Wildmoor Sandstone Formation (`Upper Mottled
Sandstone'). |
|
An
extensive exposure of bright red Triassic sandstone that shows elaborate
and extensive sedimentary structures. Designated an SSSI; the section
shows a variety of sedimentary structures including flat bedding;
planar-; tubular- and trough- cross-bedding. 150 metres long by 10
metres deep following the path of the road. The extensive and great
variety of sedimentary structures in this Lower Triassic sandstone
indicate that deposition occurred in a sandy alluvial system with the
river flowing towards the north-west. Some horizons within the sands may
have been deposited as a result of wind action and it is therefore an
important site for the study of Triassic environments. |
Take the A454 Wolverhampton Road out of Bridgnorth. After about a
couple of miles there is a turning on the right hand side of the road
situated between a garage and the Wheel o Worfield Public House. Turn
right here signposted Claverley. Follow this narrow country lane for
about two miles until reaching a `T' junction. On the right the village
of Claverley and the church may be seen - turn left towards Shipley and
after some 200 m the road passes through a deep but narrow cutting which
is the exposure. Access is good. However; this is a deep but narrow
cutting on a single track country lane with no passing places and as
such passing traffic may prove a danger to the visitor. |
LGS Yes. The site designated a LGS as an exemplary exposure in aeolian
Triassic Sandstones with a wealth of sedimentary detail. |
Sedimentology/Stratigraphy |
| 1238 |
SO 386 802 |
Coston Manor -
Aston-on-Clun (1) |
Quarry (disused) |
Ordovician: Hoar Edge Grit (ref.1); Ordovician: Coston Beds (ref.2) |
|
On
the eastern slope of Clunbury Hill but separated from it by component F1
of the Church Stretton fault is an area of basal Ordovician grits and
sandstones originally mapped and described in detail by Dean (ref. 2). 5
specific localities were subsequently designated as forming a SSSI
notification for the stratotype sections of the Costian Stage. Access to
the area has been curtailed by the owners but special permission for a
visit was secured by Dr. Helen Boynton. Site '1' is the Upper Coston
SSSI. The outcrop is a bank 3 m wide & 1 m high. A basal pinkish grit
with small pebbles and lenses of decalcified shells visible; tend to be
flaggy at top and a massive grit at base. Dip 35° at 290 (WNW). To the
right the exposure is truncated by a fault trending 320° and showing
slickensides. Numerous brachiopods collected here and from an adjacent
temporary excavation [SO387803]. |
Discouraged by owners; a public bridleway passes from top to Clunbury
Hill to Coston Manor but is signed as not giving a through way to Aston
or Beambridge; this does however run alongside the bank exposure at this
locality |
LGS Yes. The quarries and exposures in the vicinity of Coston Manor are
designated a LGS as the surviving type sections for the Costian Stage
of the Ordovician Period |
Sedimentology/Stratigraphy |
| 1239 |
SO 387 806 |
Coston Manor -
Aston-on-Clun (2) |
Quarry (disused) |
Ordovician: Hoar Edge Grit (ref.1); Ordovician: Coston Beds (ref.2) |
|
On
the eastern slope of Clunbury Hill but separated from it by component F1
of the Church Stretton fault is an area of basal Ordovician grits and
sandstones originally mapped and described in detail by Dean (ref. 2). 5
specific localities were subsequently designated as forming a SSSI
notification for the stratotype sections of the Costian Stage. Access to
the area has been curtailed by the owners but special permission for a
visit was secured by Dr. Helen Boynton. Site '2' is the Hollies SSSI.
This is a quarry 10 m wide but only the top 1 m is exposed. This is
generally a coarse grit with abundant siliceous grains. Grit is
ill-sorted with small angular to sub-rounded grains. To the left is a
fault zone with breccia and coarse gouge trending SE. No fossils found.
[SO387806]. |
Discouraged by owners; a public bridleway passes from top to Clunbury
Hill to Coston Manor but is signed as not giving a through way to Aston
or Beambridge |
LGS Yes. The quarries and exposures in the vicinity of Coston Manor are
designated a LGS as the surviving type sections for the Costian stage
of the Ordovician Period |
Sedimentology/Stratigraphy |
| 1240 |
SO 387 807 |
Coston Manor -
Aston-on-Clun (3) |
Quarry (disused) |
Ordovician: Hoar Edge Grit (ref.1); Ordovician: Coston Beds (ref.2) |
|
On
the eastern slope of Clunbury Hill but separated from it by component F1
of the Church Stretton fault is an area of basal Ordovician grits and
sandstones originally mapped and described in detail by Dean (ref. 2). 5
specific localities were subsequently designated as forming a SSSI
notification for the stratotype sections of the Costian Stage. Access to
the area has been curtailed by the owners but special permission for a
visit was secured by Dr. Helen Boynton. Site '3' is the Hollies (N) SSSI.
THis is a quarry about 10 m wide and 2 m high but totally filled with
farm rubbish (netting corrugated sheet etc) and obscured by trees soil &
moss [SO387807]. |
Discouraged by owners; a public bridleway passes from top to Clunbury
Hill to Coston Manor but is signed as not giving a through way to Aston
or Beambridge |
LGS Yes. The quarries and exposures in the vicinity of Coston Manor are
designated a LGS as the surviving type sections for the Costian stage
of the Ordovician Period |
Sedimentology/Stratigraphy |
| 1241 |
SO 390 806 |
Coston Manor -
Aston-on-Clun (4) |
Quarry (disused) |
Ordovician: Hoar Edge Grit (ref.1); Ordovician: Coston Beds (ref.2) |
|
On
the eastern slope of Clunbury Hill but separated from it by component F1
of the Church Stretton fault is an area of basal Ordovician grits and
sandstones originally mapped and described in detail by Dean (ref. 2). 5
specific localities were subsequently designated as forming a SSSI
notification for the stratotype sections of the Costian Stage. Access to
the area has been curtailed by the owners but special permission for a
visit was secured by Dr. Helen Boynton. This is Site '4' Coston Cottage.
This is a large excavation 25 m wide and up to 2 m high in massive and
cross bedded fining upward units. Middle of face shows a zone of joint
movement in direction 330° with near horizontal slickensides; also some
bedding plane surface movements (SO390806] |
Discouraged by owners; a public bridleway passes from top to Clunbury
Hill to Coston Manor but is signed as not giving a through way to Aston
or Beambridge |
LGS Yes. The quarries and exposures in the vicinity of Coston Manor are
designated a LGS as the surviving type sections for the Costian stage
of the Ordovician Period |
Sedimentology/Stratigraphy |
| 1242 |
SO 391 804 |
Coston Manor -
Aston-on-Clun (5) |
Quarry (disused) |
Ordovician: Hoar Edge Grit (ref.1); Ordovician: Coston Beds (ref.2) |
|
On
the eastern slope of Clunbury Hill but separated from it by component F1
of the Church Stretton fault is an area of basal Ordovician grits and
sandstones originally mapped and described in detail by Dean (ref. 2). 5
specific localities were subsequently designated as forming a SSSI
notification for the stratotype sections of the Costian Stage. Access to
the area has been curtailed by the owners but special permission for a
visit was secured by Dr. Helen Boynton. Site '5' is Quarry House. Behind
the house is a new excavation but the best exposures are in a largish
quarry to the right which is 10 m wide and up to 3 m high. Well bedded
sandstone/grit units with good sedimentary features can be recognised as
discrete units representing single ‘events’. These vary in thickness
texture grain size and degree of cross bedding. The top of each unit may
be an erosion or rippled surface. Dip 10° SE. Exposure is continued to
the right by a further large quarry with a very broken face 20 m long
and up to 4 m high and containing some very massive units; very coarse
with ill-sorted pebbles up to 10 mm across [SO391804]. |
Discouraged by owners; a public bridleway passes from top to Clunbury
Hill to Coston Manor but is signed as not giving a through way to Aston
or Beambridge |
LGS Yes. The quarries and exposures in the vicinity of Coston Manor are
designated a LGS as the surviving type sections for the Costian stage
of the Ordovician Period |
Sedimentology/Stratigraphy |
| 1259 |
SJ 3921 2065 |
Ruyton Cliffe
(reservoir) |
Quarry (disused) |
Triassic: mostly Keuper Series: Ruyton and Grinshill Sandstones;
possibly Upper Mottled Sandstone below. |
West-facing scarp of Ruyton Cliffe. |
Massive Ruyton Sandstone with many holes produced by weathering. The
face is red-brown in colour; about 4 m high and the rock finely
arenaceous and well-sorted. The basal horizon is approx. 1.5 m thick
with prominent iron-rich concretions. At the top of the exposure;
thinner irregular layers can be seen. The surfaces here are fairly
fresh and there is noticeable orange-red iron staining on the RHS.
There was evidence of a fault; infilled with rubbly rock and spheroidal
weathering present. There is a good view westwards over the
drift-covered plain towards the Ordovician Breidden Hills and the
Berwyns. |
From a public footpath. |
LGS Yes. Designation because there is structural; and weathering
interest as well as good faces of representative Ruyton Sandstone
combined with an instructive view. |
Mineralogy/Petrology |
| 1261 |
SJ 3932 2051 |
Ruyton Cliffe
(S) |
Quarry (disused) |
Triassic: Keuper Series: Ruyton Sandstone. Sheet 138; Wem |
Scarp slope of Ruyton Cliffe facing south. |
This is the best of the old quarries on the Cliffe; it is circular with
a rock entrance. One of the massive vertical faces is approx. 12 m high.
There is a gradual colour change upwards from a bright red to beige at
the top. About 4 m from the base is a prominent boundary below which the
rock is massive and red-brown; above it there are clear; large-scale;
unidirectional cross-bedded units. The boundary roughly coincides with
the colour change. The uppermost 1.5 m are thinly bedded and appear to
be lying horizontally above the cross-bedded strata. There are many
large joints and possible faults in the east corner. Continuing to the
top of the hill via the footpath the topmost beds of the quarry can be
examined although a vertical drop makes it necessary to be careful. The
sandstone here is light in colour and is traversed by numerous
silica-filled or iron-rich joints which stand proud from the rock but
have no real consistent direction. The viewpoint from the picnic area at
the top is magnificent. |
Via an old track through the rocky entrance which branches off the
footpath. |
LGS Yes. Designation because the sequence through the Ruyton sandstones
displays many features of structural and sedimentary interest. |
Sedimentology/Stratigraphy |
| 1262 |
SJ 3940 2415 |
Ruyton
(Blackberry Hill) |
Quarry (disused) |
Triassic: Keuper Series: Ruyton Sandstone. Sheet 138. |
Quarry is cut in the high cliff alongside the R. Perry. |
The rock is the typical Ruyton freestone; a fine-grained; dull red
sandstone with yellow blotches and linear patches of buff. The height of
the exposure is up to 9 m and lateral extent 30 m. Because of the
chisel marks it is difficult to see detail of sedimentary structures
although there is evidence of cross-bedding. The top 2 m show strata
which are very broken and irregular. At the furthest end of the quarry;
in the SW corner; is a prominent joint filled with sand fragments and
thin laminae running parallel to the joint plane. It is possible this
is a fault but there seems to be no conclusive evidence and Pocock
refers to it as a joint. The direction of the joint plane is NE/SW.
Adjacent to this feature is a face with smaller joints crossing each
other at angles of approx. 120 and 60 degrees forming a diamond pattern.
A few metres north from this face a small but clear fault can be
examined. The fault plane runs nearly parallel to the face again in a
direction of NE/SW. There are about 6 m of slickensided fault plane
exposed (3 layers of slickensided surfaces being visible). The gap along
the fault is about 6 m and is infilled with some mineralisation but also
with brecciated fragments. The slickensides appear to show near-vertical
movement. |
There is a convenient footpath but the quarry is a few metres off it
through a wire fence by the river. |
LGS Yes. Designation because the site is a clear example of Ruyton
Sandstone with interesting fault and joint structures. |
Mineralogy/Petrology |
| 1264 |
SJ 4755 2290 |
Webscott
T-junction |
Quarry (disused) |
Triassic: Sherwood Sandstone Formation: Wildmoor Sandstone overlain by
Grinshill Sandstone. Wem Sheet 138. New nomenclature from Toghill:
'Geology in Shropshire.' |
SW
facing scarp of sandstone ridge. |
A
large quarry; one of several along this ridge; with exposures up to 12 m
high. Faces are vertical and massive with few visible bedding planes.
The sandstone is a dull but sometimes brighter red with a few light
blotches which is crossed by numerous; sub-parallel joints. The joints
are generally infilled with harder; siliceous material and trend approx.
25 degrees off the vertical. The sandstone is fine and well-sorted.
There are noticeable holes; the product of weathering; and indistinct
cross-bedding. At the top are about 2 m of thin bedded; yellowish;
cross-bedded sandstones; belonging to the Grinshill Group. The NE face
is crossed near the top by projecting; infilled joints. The joints are
very interesting and on the left of the steps are several sub-parallel
ones with perhaps slumping; and one very obvious infilled example which
may be a fault. There are extensive exposures along the road here and
the whole stretch from Myddle to Harmer Hill invites closer examination. |
Public access from the road. |
LGS Yes. Designation because it is an extensive and good example of Wildmoor Sandstone (U. Mottled) and its boundary with basal Helsby
Sandstone (Grinshill Sandstone) which displays interesting joint
structures. |
Structure and Sedimentology/Stratigraphy |
| 1265 |
SJ 4765 2339 |
Webscott Woodlands |
Quarry (disused) |
Triassic: Sherwood Sandstone Formation: Wildmoor Sandstone (Upper
Mottled) overlain by Helsby Sandstone (Grinshill Sandstone). |
On
SW-facing scarp slope of sandstone ridge. |
Rocks here are higher in the sequence than at SJ 476229 and a better
examination of the Grinshill strata is possible. The boundary is
unclear on the south-east side of the footpath but on the north side 2 m
of yellow; cross-bedded Grinshill sandstone can be seen lying on top of
the redder Wildmoor sandstone on a vertical cut quarry face. Also; a
large vertical joint or fault with bright red sandstone infilling a gap
of 0.5 m can be examined close by. Further into the quarry; still on
the north side; 5 m of thinly bedded sandstone; mostly covered by moss
and algae; with harder infilling of small joints forming a criss-cross
pattern; seems to be Wildmoor sandstone; but a few metres on; a natural
exposure of about 4 m of Helsby basement beds; the light-coloured
Grinshill sandstones is exposed. It is possible to find a similar
horizon opposite on the south side. Glacial granite erratics lie by the
footpath. |
A
public footpath goes through the quarry and from it; looking SE the
current workings for sand can be seen. |
LGS Yes. Designation because the Wildmoor and Grinshill boundary is
clear and accessible; joint patterns and structures are interesting and
some present quarrying activity can be seen. ( It may be that this whole
stretch of exposures from Myddle to Harmer Hill should be designated one
LGS. The two largest quarries have been described in this report and in
SJ476229) |
Sedimentology/Stratigraphy |
| 1267 |
SJ 5148 2415 |
Clive (church) |
Track/roadside |
Triassic: Sherwood Sandstone Formation: Grinshill Sandstone. Sheet 138
Wem. |
NW
end of Grinshill (SE end of Clive). |
Grinshill yellow sandstone is here very thinly bedded and is about 4 m
high. The interest of this site lies in the spheres of barytes densely
packed in the layers of sandstone. They vary in size from less than 10
mm to 50 mm and are scattered randomly within the rock. Although the
condition of the exposures is not everywhere good there are enough clean
surfaces to examine these small barytes nodules and they are an unusual
feature. They can be seen again in the rock of the steps that lead to
the school; standing proud of the surface in places and also in a red
sandstone exposure about 10 m from the SE corner of the churchyard.
Blocks of sandstone containing the barytes spheres are found in the wall
opposite this corner. |
Public road and footpath. |
LGS Yes. Designation because concentrations of barytes have here formed
spheres in sandstone; an unusual phenomenon and therefore of much
geological interest. |
Mineralogy/Petrology |
| 1272 |
SJ 526 238 |
Grinshill
Quarries |
Quarry (disused) |
Triassic: Sherwood Sandstone Group (Grinshill Sandstone Member) and
Mercia Mudstone (Tarporley Siltstone Formation and Bollin Mudstone
Formation). New nomenclature from Thompson: 'Guide to History and
Geology of Quarrying......in Corbet Wood; Grinshill' |
Near the top of SW facing scarp slope of Grinshill. |
At
locality 4 on the nature trail; a short path leads to an excellent old
quarry face which reveals a complete succession of the local Triassic.
Buff/white Grinshill Sandstones; about 7 m thick; lie at the base of the
exposure which towers to a height of approx. 18 m. These display a
sub-horizontal erosion plane near the base; and cross-bedded foresets of
a former sand dune 4 m high. There is a distinct break marking the
lower beds of Tarporley Siltstones (flagstones here) which have a
thickness of 8-9 m. The original discoveries of bones and fossil
footprints of Rhynchosaurus came from a comparable horizon to this rock
unit within these Bridge Quarries. Both of the lower rock units are
crossed by near vertical joints; and a fault on the west of the
exposure. At the top of the face are about 2 m of Bollin Mudstones. A
rough steep path on the west leads to an overhang of Grinshill
Flagstones which here display current and wave ripple marks. On the east
side of the face; another short path leads past an excellent
slickensided fault plane; aligned at 37 degrees and dipping 85° SE. The
path ends at a rock barrier over which another large; very deep quarry
can be seen. (see slides). Continuing along the main path for a few
metres; the west end of Bridge Quarries is reached. The succession is
repeated here and again the boundary between Grinshill Sandstones and
Tarporley Flagstones is easily seen by the change to thinner strata and
a recess in the face. Another recess is seen about two thirds of the
way up the face; this may represent another erosion surface (see slide). |
Easy; public access from the main footpath on the nature trail. |
LGS Yes. Designation because the original fossil bones and footprints
were discovered here; the face is excellent and accessible; and as well
as the complete succession there are sedimentary structures; joints and
faults to be seen. Suitable for groups of students and is a very good
site for fieldwork. |
Fossils and Sedimentology/Stratigraphy |
| 1274 |
SJ 5262 2380 |
Grinshill
Working Quarry |
Quarry (working) |
Triassic: Sherwood Sandstone Formation (Grinshill Sandstone Member) and
Mercia Mudstone Formation (Tarporley Siltstone Formation and Bollin
Mudstone Formation). New nomenclature from David Thompson: 'Guide to
History and Geology of Quarrying' 1995. |
Quarry at top of south-facing scarp of sandstone hill; Grinshill which
stands prominently above the plain. |
Most of the working quarry can be seen from a view-point a short
distance along the path leading NW from Corbet Wood carpark (GR SJ
52602875). The rocks can be seen exposed in near-horizontal layers; the
variation in colour from cream to red emphasising the changes in
lithology (see slide). Strata actually dip 5° N towards the Cheshire
Basin. The lower part of the quarry is composed of whitish massive
Grinshill sandstone ca. 20 m thick. Skeletal fragments of an early
lizard-like reptile; Rhynchosaurus have been found in this quarry and
the possibility of finding more of these is the reason for its
designation as part of an SSSI for vertebrate palaeontology. Above these
sandstones lie the Grinshill Flagstones of the Tarporley Siltstone
Formation. The boundary between these and the massive sandstones below
is clear to see. The whitish flagstones are 7-9 m thick and between the
layers are greenish siltstones; known for their sedimentary structures.
Above the siltstones a few metres of red siltstones and mudstones of the
Mercia Mudstone Group form the unproductive overburden to the quarry. |
The viewpoint is readily accessible from a public path leading from the
Corbet Wood carpark. Permission to enter the quarry may be obtained
from the office on site. Small groups could be accommodated. |
LGS Yes. Designation because the quarry since Darwin and Huxley's time
has been known for the reptile footprints and there is a possibility of
finding more. There is a good exposure of the Triassic succession
described above and the dyke represents one of very few exposures of
rocks in the county dating from the Tertiary Period. |
Sedimentology/Stratigraphy |
| 1276 |
SJ 3850 1922 |
Nesscliffe Hill |
Quarry (disused) |
Triassic: Sherwood Sandstone Formation: Wilmslow Sandstone; and Helsby
Sandstone (Ruyton Sandstone). Sheet 138 (with old classification) |
Abrupt vertical cliff at southern end of Nesscliffe Hill. |
In
this main quarry; the faces are impressive and vertical; the height
being 25-30 m. There is a transition from the Wilmslow Sandstone to the
Ruyton Group from bottom to top of the cliff but no sign of a boundary.
The beds at the bottom are deep red and soft. The colour becomes
yellower and less deep red upwards in the sequence. Many joints; some
curved; cross the face diagonally. There are cross-bedded units halfway
up the quarry face but no sign of true bedding. The overall impression
is of a high face of massive sandstone. At the top; the beds are less
massive and show curving structures which may represent channelling.
The Ruyton Sandstone ends abruptly here being cut by the powerful E-W
fault; a branch of the main Axial Fault of Great Ness and Middle. A few
metres NW is Kynaston's Cave; inhabited until at least the 18th century
and excavated into another high cliff in the Ruyton Sandstone. The
rocks are weak; red with patches of yellow and noticeably cross-bedded.
Unfortunately; the chisel marks left after quarrying tend to obscure
detail of sedimentary structures. There are other similar exposures
especially at the south end of the hill. |
Via public footpaths |
LGS Yes. Designation because this is an excellent; accessible example
of the transition between Wilmslow and Ruyton Sandstones. Would
recommend whole of Nesscliffe Hill as LGS. |
Sedimentology/Stratigraphy |
| 1278 |
SJ 4875 2140 |
Pim Hill |
Natural exposure |
Triassic: Sherwood Sandstone Formation (Bunter): Wildmoor Sandstone
(Upper Mottled) and Helsby Sandstone (Keuper) Grinshill Sandstone.
Sheet 138 Wem; and Toghill 'Geology in Shropshire' |
Near the top of the scarp slope 300m N of Pim Hill. |
The old vein forms a gorge running approx. N-S along a fault. It is from
4-8 m wide and up to 6 m high. The best exposure is at the southern end
where it narrows and is steeper. Grinshill Sandstones; beige in colour
with specks of red; brown and grey and with manganese oxide; are exposed
on the east side. This rock is uniform in texture and is a medium
grained sandstone. On this side of the vein are good examples of
slickensides with polished; mineralised surfaces. The mineral is white
but not CaCO3; possibly being BaSO4. The fault planes trend SW-NE. On
the west side of the vein the rock is redder; finer and softer; being
Wildmoor Sandstone. There is evidence here of a continuation of the
SW-NE trending fault but no mineralisation. The gap; possibly the fault
line; varies in thickness; being up to 0.5 m at the top and filled with
loose reddish sand. Longer investigation; at the head of the vein may
reveal the boundary between the two main sandstone types. |
From the public footpath a well-used path through the woods (but not a
right of way) goes past the site. |
LGS Yes. Designation because the site exposes Grinshill and Wildmoor
Sandstones on opposite walls of a faulted vein which also displays good
evidence of subsidiary faulting. |
Mineralogy/Petrology |
| 1279 |
SJ 6995 0770 |
Telford Town Park - Randlay
Pool (SW) |
Natural exposure |
Upper Carboniferous: Upper Coal Measures: Coalport Formation. |
SE
facing slope of sandstone ridge west of Randlay Pool. |
This exposure consists of massive; yellow; brown-weathering sandstone;
beds being over a metre thick. This is part of the 'Thick Rock' of the
Coalport Formation. The overall height of the exposure is up to 5 m and
it extends laterally for about 20 m. The texture is that of a coarse
arenaceous rock with specks of black carbonaceous material.
Cross-bedding can be seen within the beds. About half way up the face
the rock is more thinly stratified; typical thickness being 0.2 m; the
appearance being more flaggy. There is one noticeable infilled joint
which forms a chimney-like structure (see slide 25). There is an
example of what appears to be channelling with fine multi-directional
cross-bedding (slide 26) and softer; recessed area below a massive
horizon made up of alternating; very thin; carbonaceous and sandy
laminations (slide 27). The dip of the beds is N/NE at an angle of 5°
or 6°. |
In
the middle of a public park with footpath access. |
LGS Yes. Designation because this is an excellent example of the 'Thick
Sandstone' of the Coalport Formation with a variety of sedimentary
structures. Public access and substantial size of exposure make it a
good site for group visits. |
Sedimentology/Stratigraphy |
| 1280 |
SJ 7035 0765 and 7025 0760 |
Telford Town Park - Blue
Pool (SE) |
Natural exposure |
Upper Carboniferous: Upper Coal Measures: Coalport Formation. |
NE
facing slope of plateau-like terrain. |
Approaching from the southern end on the east side of Blue Pool the
Coalport Formation forms a steep slope down to the pool (this is mostly
covered with vegetation but at the foot are large fallen sandstone
boulders). Although moss covers the surfaces; nodules of iron pyrites
up to 50 mm diam. can be seen weathering out of the sandstone. About 200
m further north-east are cliffs of mainly decaying grey/brown shale
which clearly undergo slippage. Sometimes the shale is very clayey and
blue in colour - hence the name of the pool. A discontinuous layer of
hard sandstone blocks occurs 1.5 m from the top and 4 m below that is
another such horizon. To the right of the most obvious sandstone layer
is a distinct 'break' which would suggest a fault; especially as a small
rivulet flows down there and exposes the shale. Iron nodules can be
picked up and the sandstone blocks at the foot of the slope contain
well-formed iron pyrites crystals. There is more massive sandstone at
the NE end of the pool. The dip of strata on this side of Blue Pool is
difficult to ascertain but Sheet 60 gives a 7° dip to the SE. Dips vary
round here probably due to faulting. |
A
public footpath goes around Blue Pool so access is easy. |
LGS Yes. Designation because the site demonstrates typical Coal Measure shales and sandstones in the middle of a park with unusually good public
access. Reflects economic history of area and is good educationally. |
Mineralogy/Petrology |
| 1294 |
SO 386 932 |
Green Farm - Wentnor |
Quarry (working) |
Precambrian: Longmyndian: Wentnor Series: Bridges Group |
Side of valley (of river E Onny) |
This currently worked excavation is a conspicuous scar when viewed
looking east from the Inn on the Green on the Bridges to Bishops Castle
road. It proves to be a current working for farm hard-core some 0.5 km
north of Wentnor. Size is some 40 m long and 4 m high aligned near
north-south. As a result the excavation is inclined at some 20° to the
strike of the typical Bridges Group siltstones and sandstones which dip
70° WNW. It is therefore a good section showing both bedding planes
(usually darkly stained) and sedimentary detail of which the sandstones
are massive and the siltstones finely laminated. The position
corresponds to or is very close to locality 6 of figure 8 p.51 in the
Memoir for the Church Stretton Sheet 166 (Greig et al. 1968). It is thus
near the axis of the core zone representing the fold axis of the
Longmyndian syncline (ibid p.50). The chief value of the exposure is
thereby as a source of clean and fresh specimens showing sedimentary
structures indicating younging direction. Several of the siltstone units
have textures resembling those of plate 3 facing p.51 in the memoir. A
second visit was made to collect samples (with permission of owner). A
number showing sedimentary variation in colour of bedding were collected
but also specific cases of ripple marks rain pits and flute casts were
found. The last three were consistent with a younging direction to the
west; i.e. beds not inverted. The former were cut and polished (slabbed)
and a younging direction also to the west was confirmed; from
recognition of sedimentary units deposited by waning currents having a
thin upper layer of darker mudstone often with a sharply delineated top
surface. |
From the centre of Wentnor village proceed north taking the lane
signposted ‘Bridges 3 miles’. The quarry is 300 m further in a field on
the left and approached through a metal gate and track. It lies on
private ground. |
LGS Yes. A good site for bedding; bedding planes; joints; dip measurment and of course way-up evidence. Nice rural views across fields
and river to public house. |
Structure and Sedimentology/Stratigraphy |
| 1296 |
SO 4875 9382 to SO 4905 9320 |
Woodgate Batch |
Bank |
Precambrian: Uriconian: Woodgate Batch Andesites and Dacites |
Over-deepened stream way; relatively straight although not
fault-controlled; in part a gorge feature |
The section runs from a point 600 m SSE of Battle Stones to Greystones
Cottage and comprises ground on both sides of the stream to a max.
distance of 150 m. It thereby includes all the rocky outcrops crags and
cliffs which line the side of the gorge sections. It is assumed in the
absence of specific comment in the memoir (Greig et al. 1968) that the
rocks are mainly sub-aerial lava flows although some occasional tuffs
bands are mentioned. Some 10 individual outcrops were examined and these
seem to cover the principal characteristics. These are: (1) SO4905 9315;
a 4 m high X 2 m square outcrop of andesite with some phenocrysts and
showing slight brecciation; most notable are strong smooth perpendicular
joint planes suggestive of columnar jointing. (2) around SO489935 3
hillside crags up to 4 m high variously brecciated.. (3) SO4885 9358 a
hill top at 303 m AOD. A very weathered outcrop showed distinct flow
banding. (4) SO4880 9360; the top of a complex broken ridge which
plunges steeply down to the stream below trending 260°. To the right the
lowest crags are strongly jointed and form a step topography due to
apparent bedding; to the left the lowest point is marked by a 8 m high
face; very weathered with a distinct lamination and patches of
brecciation. These latter two may represent tuffs. (5) On the west side
of the stream between SO486937 and SO487934 are several rocky bluffs
with scree below two of them; a scree slope at SO4874 9345 yielded rocks
of various types; viz. fine grained; porphorytic dark purple slightly
flow banded; deep pink sharp edged and slightly vesicular and a pale
coarse grained tuff. (6) The quarry at SO4877 9340 receives a
description in the memoir; p.23. It has recently been worked for
hard-core. Semicircular in section it has two distinct levels. The upper
level (half-circle diameter 15 m) is now 3/4 grass covered due to rapid
decomposition of the andesitic rock. The ‘spheroids’ described in the
memoir are scarcely recognisable in the visible rock at the top left.
Only notable feature are two totally rotted areas of pale gray and
yellow colour. The lower ground level; diameter 24 m; shows massive rock
on the left hand side; a porphyritic andesite variously grey; green or
pink. It breaks along the joint planes to produce irregular flat sided
pieces which can have razor sharp edges! To the right the rock is softer
and more resembles that in the upper level. A distinct 3 m wide fault
zone is visible with totally rotted fault breccia. (7) An impressive
vertical cliff lying below SO4900 9380 is dangerous if approached from
the footpath above and has no public access from below. ACCESS: The most
direct access; which leads to (5) & (6) above; is by a bridleway
starting at SO486928 just west of Woodgate Cottage on the Church
Stretton to Much Wenlock road 1 mile east of Hope Bowdler. 600 m
further east a more convoluted footpath starts at Woodgate Farm; passes
Gray Stones and gives access to points (1) to (4) above. |
The most direct access which leads to (5) & (6) above is by a bridleway
starting at SO486928 just west of Woodgate Cottage on the Church
Stretton to Much Wenlock road 1 mile east of Hope Bowdler. 600 m further
east a more convoluted footpath starts at Woodgate Farm passes Gray
Stones and gives access to points (1) to (4) above. |
LGS Yes. These andesites and dacites cover a large area and this
designation reflects their best exposure. A wide range of exposure type
even if the rock type is ‘difficult’. A de facto type section with some
geomorphology. A neglected area which gives an experience of
exploration. |
Mineralogy/Petrology |
| 1297 |
SO 3863 8658 |
Plowden Woods scarp -
Lydbury North |
Track/roadside |
Silurian: Wenlock Shales; equivalent to the Silurian: Aston Mudstone |
Crest of apparent scarp |
This section in Wenlock Shales shows development at the top of the scarp
in Plowden Woods. The hard grey mudstone/siltstone exposed in the quarry
at the foot of the slope (SO383867) continues almost to the top of the
scarp slope. This exposure shows the top few metres becoming much more
calcareous and containing an allogenic shelly fauna. At the base of the
section bedding is massive (partly due to bioturbation); in the upper
parts this bedding becomes flaggy due to unloading. However an
increasing calcareous content is evident and some parts have decalcified
to a deep brown or brilliant red-ochre coloured rottenstone. Associated
with such decalcification is a prolific (occasionally dense) fauna which
becomes much more distinguishable from the bioturbated background. This
fauna is dominated by small brachiopods including some strongly ribbed
varieties with Dicolesia biloba particularly prolific; occasional
Beyrichian ostracodes (possibly Beyrichia salopiensis as figured in
ref.1) and in an adjacent exposure trilobite fragments (probably of
Dalmanites sp.). This fauna is clearly allogenic and accumulates as
small lenses or coquinas dispersed in the moderately bioturbated
sediment. Further the lithology and fauna have strong resemblance to
beds of the Elton Formation as exposed in the Goggin Road sections of
Mortimer Forest. In view of the situation of this exposure on the
junction between the shelf sediments of the Church Stretton sheet 166
and the off-shelf sediments of the Montgomery sheet 165 it is concluded
that this exposure is better classified as one of the Aston Mudstone
Formation of sheet 165 rather than Wenlock Shale of 166. In view of
subsequent developments in adjacent Edgton beds of the Oakley Mynd
Formation and Bailey Hill Formation this is a crucial exposure in
delimiting the boundary at a specific point in geological time between
shelf and off-shelf sedimentation. Palaeoenvironment: Shallowing water;
possibly tidal or storm affected but too silty for actual limestone to
form. |
Section lies some 40 m from the footpath followed by the Shropshire Way
and no explicit notice or barrier intervenes. Via the footpaths used by
the Shropshire Way either from Plowden or Edgton one arrives at a path
junction on the crest of an obvious scarp. From this junction follow the
path to the east for 40 m where the section will be seen in a branch
track which begins to descend the scarp. |
LGS Yes. Designated a LGS as a crucial exposure marking the boundary
between shelf and off-shelf sediments at the time of the Silurian Wenlock/Ludlow series transition. |
Fossils and Sedimentology/Stratigraphy |
| 1301 |
SO 2782 9763 to SO 2794 9814 |
Hagley Upper Ridge -
Chirbury |
Mine/adit |
Ordovician: Caradoc Series: Hagley Volcanic Formation |
A
whaleback ridge with offsets due to faulting and a good viewpoint |
With alternating hard and soft beds and strata dipping 45° to the west;
a ridge and hollow topography is common in the western margins of the
Shelve Inlier. However; this particular ridge of resistant volcanic
tuffs surrounded on both sides by readily weathering shales is a gem
showing a text book example of a whale-back hill. It has the additional
features of the type section for the Hagley Volcanics; some easily
recognised faulting; and evidence of old mine workings. The roadside
quarry SO27829763 is the type section for the Hagley Volcanic Member (Whittard
& Dean; 1979). The open part nearest the road shows what appears to be a
massive pale fine sandstone; slightly micaceous; however; slabbing
confirms that it is devoid of quartz grains; quite soft and consistent
with a very fine grained tuff. Notable is a distinct mottling usually
taken as diagnostic of bioturbation. Coincidentally the polished surface
cut a longitudinal section of the polyzoa Prasopora grayae (BPF; p.53).
To the left a public footpath follows the western margin of the ridge.
There are numerous slab exposures on the right and confirmation of the
volcanic nature of the rock with; for example; lithic tuffs of clasts of
size up to 10 mm. After 300 m there is an embayment to the right where
an adit (SO27859789) indicates old mine workings for barytes. A second
path branches to the right and ascends to the crest of the ridge passing
further workings and an old level showing fault gouge and vein quartz.
This fault is represented on the ridge by a hollow with the highest
point to the right at SO27959785. Hereabouts numerous small quarries
confirm the variability of the volcanics with examples varying from the
mottled type of the roadside quarry to centimetre scale lithic tuffs.
The ridge crest offers a superb viewing platform both of the local ridge
and hollow topography and wider from Corndon Hill; the Kerry Ridgeway
Silurian scarp and towards Newtown and Wales. Continuing north the ridge
suffers a number of offsets which clearly relate to the mapped fault
pattern and then a return can be made via the original footpath. |
Hagley is some 2 km south-east of Chirbury and is reached by the road to
Priestweston some 1.5 km from the Whittery Bridge. The roadside quarry
in trees is adjacent to a small pumping station surrounded by a wire
netting fence. |
LGS Yes. A text book geomorphological feature allied with
comprehensible volcanics and evidence of old mine workings; part of
Shelve Inlier ore field - barytes zone. A wide range of features
including whaleback hill; variable volcanics; tuffs; old mine workings;
faults; local topography and viewpoint. Type section and question
whether fine tuffs are bioturbated. |
Geomorphology/Landscape |
| 1302 |
SO 471 932 to SO 490 945 |
Hope Bowdler
Hill |
Crag |
Precambrian: Uriconian Volcanics |
Differential erosion of hard volcanic rocks compared with surrounding
softer sediments; character of flanks of hill determined by nature of
enclosing faults. |
Of
the six ‘Church Stretton Volcanic Hills’ identified and described by the
Geological Survey (Greig et al. 1968) that of Hope Bowdler is the only
one completely defined by faults; these being the normal Cwms-Hoar Edge
F3 fault of Lapworth & Cobbold together with thrust (reverse) faults
named as Sharpstones and Willstone. These enclose an elongated area with
a long axis of 2.5 km aligned SW to NE from the Gaer Stone (SO4723 9340)
to Battle Stones (SO4855 9430) and up to 0.5 km wide. The character of
the hill flanks clearly reflects the nature of the defining faults. The
NW flank is generally straight and of a uniform slope 1 in 2 (ca. 25°)
at the foot of which a hedge line marks the change to the lower angle
and softer sediments of the Cwms inlier. In contrast the SE flank is
more undulatory with its slopes marked by various steep outcrops
overlooking the line of change to gentle slopes which marks the mapped
position of the Willstone thrust. Between these faults is a single
rounded grassy ridge with four distinct ‘tops’ at 390 425 426 and 403
metres together with intervening cols; all being linked by a footpath
which is very popular with hill walkers. The stratigraphy is according
to Greig (1968) a simple downward simple sequence of Andesites
Conglomerate Rhyolites (with andesites and tuff bands) together with two
areas of intrusive dolerite. Outcrops of the more basic rocks carry a
heavy patina of staining and lichen with variable degrees of alteration.
The rhyolites and conglomerate are somewhat fresher but overall it
requires some familiarity before rock type can be confidently identified
in the field. Fortunately all significant exposures are easily
accessible from the ridge footpath and these more or less confirm the
disposition according to the 1:25 000 Geological map; Sheet SO49; and
Figure 4 (facing page 18) of the memoir (see however the attachment). As
a ‘geological site’ the Hope Bowdler Hill has the following qualities
germane to a designation: (1) as a geomorphological entity it provides
a convincing example of the role of fault type in the sculpture of a
landscape feature; (2) rock exposures are sufficiently distinctive to
allow for field recognition of local faulting; (3) there is an
intriguing contact between the conglomerate and dolerite intrusion at
SO4734 9345; (4) there is a particularly fine section showing rhyolite
xenoliths in a dolerite matrix (SO4740 9345 to SO4344 9350); (5) rock
outcrops along the SE flank raise the question as to how far if at all
they have been affected by the adjacent thrust; (6) actual outcrops of
the conglomerate bed provide evidence to support the interpretation by
Pauley (1991) that this is a representative of the Longmyndian and
overlies both rhyolite and andesites unconformably; (7) it provides
exemplary viewpoints both of the cuesta landscape to the SE and across
the Cwms sedimentary inlier to Caer Caradoc; (8) there is a sequence of
exposures along the ridge from Gaer Stone to Battle Stones well able to
support a geological trail or itinerary with potential to extend NE to
Sharpstones and Hillend or SW to Ragleth Hill. (NOTE: An outline of such
an itinerary is attached to this report as a vehicle for presenting
fuller data of this survey) |
A
footpath apparently established by common usage runs from Gaer Stone to
Battle Stones. The former can be reached by public footpath from
Sandford Seat (SO468933) 1.5 km from Church Stretton on the Much Wenlock
road; the latter by public footpath from Willstone Upper Farm
(SO492953). A public bridleway from Hope Bowdler village crosses the
ridge at a col (SO482942) 400 m WSW of Battle Stones. |
LGS Yes. Designated a LGS as a compact and accessible Precambrian
volcanic sequence showing features attributable to faulting intrusion
and unconformity plus xenoliths; also offers comparison with other
sequences such as that of Caer Caradoc. Feature mapping; rock types
associated with Island Arcs and geomorphology. offers scope for
discussion of a revised or new interpretation of the stratigraphy.
Exemplary viewpoint pertaining to local geology. |
Mineralogy/Petrology |
| 1303 |
SO 4418 9238 to SO 4425 9170 (?) |
Rudges - Little Stretton |
Quarry (disused) |
Precambrian: Longmyndian: Stretton Shales. Silurian: Llandovery: basal
Pentamerus Beds |
Top edge of very steep 40 m high bank dropping down to stream |
Interesting exposures in Stretton Shales which reveal the overlying
basal Silurian grits. The several exposures are described here as linked
in a roughly 400 m long section. The section begins at the gate (marked
G1 on the attached map) at SO4418 9238 from where the path runs south
along the top edge of the Ashes Hollow stream bank. In 50 m are
exposures of shales (locality 1) with an anomalous dip to the NE of 65°.
At (2) (SO4417 9229) is a small quarry with a strong joint face trending
220° in Stretton Shales. The north side shows these shales with low dip
curving over to near vertical; the south side is of dolerite which
contacts the shales near the joint face. Locality 3 is an exposure of
shales striking at 220° but affected by the distortion of kink banding.
Locality 4 (SO4417 9211) is a second quarry 16 m wide and 3 m high in
the eastern bank of the path. Here the shales dip more normally to the
west but with very variable dips; 30° to 80°; and very much affected by
flexure and incipient kink banding. On the west side of the path is
dolerite exposed as a narrow rib 18 m long opposite the quarry. Beyond
the quarry is a gate which gives access to a sunken lane. Locality 5
(SO4416 9208) is just beyond this gate and comprises a number of small
exposures of highly brecciated shales which would seem to correspond to
a fault breccia (although no such fault is shown on the BGS 1:25 000
map). From locality 5 rough tracks lead just south of east in 150 m to a
gate G2 on a surfaced farm track; 50 m south along this track locality 6
(SO4425 9197) presents exposures of the Silurian. These are of several
square metres of admixed pebbly conglomerate; purple grits and finer
sandstones on both sides of the track with a dip to the south-east of
25°. These are clearly banked against underlying; but unexposed;
Stretton Shales forming a beach deposit. No fossil casts were found
apart from tenuous indications of columnals. The exposure ends as the
track turns right leading out to the tarmac road in Little Stretton. |
via path described above |
LGS Yes. Designated a LGS as the most northerly example of the basal
Silurian unconformity in conjunction with exposures of underlying shales
showing distortions associated with faulting and dolerite intrusions.
The re-opening in August 2001 of a permissive (?) path between
Crossbanks Ludlow road Church Stretton and Little Stretton (SO445930 to
SO441920) has given access to these exposures which are significant for
understanding the phenomenon of kink banding. |
Structure and Sedimentology/Stratigraphy |
| 1306 |
SO 3102 9816 to SO 3135 9917 |
Stapeley Hill (SE) -
Worthen with Shelve |
Quarry (disused) |
Ordovician: Llanvirn Series: Hope Group; Stapeley Volcanic Formation
(BGS; 1991); Shelve Formation; Stapeley Volcanic Member (Whittard & Dean
1979) |
Landscape of ridge centred on steeply dipping volcanic rocks and valley
hollowed in softer shales both leading to plateau area of dolerite |
The single unit of three volcanic horizons of Whittard - the Stapeley
Volcanic Member (bounded to the west by shales) the Stapeley Shale
Member and (to the east) the overlying Hope Shales (Whittard & Dean;
1979; p.29) - was re-mapped by BGS as a complex of volcanic tuffs and
lavas - the Stapeley Volcanic Formation - lying within the Hope Shales.
Figure 1 shows the resultant BGS stratigraphic column and figure 2
(annotated with locality numbers) shows the area covered by this report.
Figure 3 is the OS map of the topography and outlines the surveyed area
proposed as a LGS. (1) This disused quarry centred on SO3102 9816
presents a 30 m wide and 6 m high face of massive bedded tuffs with
strong jointing and areas of spherical weathering. Low down in the
centre of the face a fresh cored area shows a grey coarse lithic tuff;
elsewhere are finer tuffs and high up on the left is a small intrusion
of chilled very fine grained dolerite(?). (2) The point SO3094 9816
marks the SW end of an emergent outcrop of volcanic tuffs which forms a
continuous rib running along the NE strike for 200 m and dipping NW 55°
to 65°. This is here considered to be a significant geomorphological
feature since it demonstrates one of the forms which can result from the
erosion of dipping rocks and bears immediate comparison with Hagley
Upper Ridge and Cwm Dingle. (3) A tor-like feature at SO3100 9825 shows
what would appear to be volcanic ‘bombs’ but in fact are larger
partially rounded clasts of rhyolitic(?) rock. (4) The NE end of the
continuous rib is at SO3104 9833 but scattered outcrops continue ahead
for some distance. (5) Off to the left (NW) the ground falls away into a
parallel running smooth sided valley. Across on the opposite side can be
seen a shale exposure (see report for Upper Stapeley Farm (E)) but
hidden from view on this nearer side is a badger set where excavation
has yielded abundant dark grey fissile shale fragments representing
interbedding of the Hope Shales. (6) Continuing along the main ridge the
ground becomes flatter and outcrops less frequent. At a crossbank a
cairn can be seen ahead apparently offset from the trend of the ridge.
This cairn at SO3124 9896 marks the near edge of a large area of
dolerite which has totally blanketed the previous landscape of ridge and
hollow forming instead a roughly level plateau. (7) This second cairn at
SO3135 9917 marks the NE limit of this survey. (8) Return to the quarry
of location 1 can be usefully made along the upper parts of the SW
slopes where further outcrops of the Stapeley Volcanics occur. It is
evidence of the stratigraphic complexity that what was considered by
Whittard to be a single unit of three volcanic horizons - the Stapeley
Volcanic Member (bounded to the west by shales - the Stapeley Shale
Member) and to the east by the overlying Hope Shales (Whittard & Dean;
1979; p.29) was re-mapped by BGS as a complex of volcanic tuffs and
lavas - the Stapeley Volcanic Formation - lying within the Hope Shales. |
The area of Stapeley Hill covered by this report is unenclosed common
land crossed by numerous paths and a bridleway linking it to the
Mitchell’s Fold Stone Circle. Convenient parking places are therefore
either the visitor’s car-park for the Stone Circle or by the chapel at
the start of the hamlet of White Grit on the Priestweston road. From the
latter is 400 m by paths which will lead to the quarry of locality 1. |
LGS Yes. A very comprehensive introduction to volcanics and intrusives
and the development of landscape features from underlying rocks.
Necessarily the type section for the Stapeley Volcanic Member. A very
evident connection between the geology and ancient peoples selection of
sites for stone monuments. A coherent combination of rock type and
landscape. 360 degree viewpoint embracing Long Mountain; Corndon Hill;
Stiperstones and Pontesford Hill - all geologically based! |
Mineralogy/Petrology |
| 1309 |
SO 446 916 to SO 458 927 |
Ragleth Hill - Church
Stretton |
Natural exposure |
Precambrian: Uriconian: Ragleth Tuffs |
Relatively erosion-resistant volcanigenic basement rocks revealed by
faulting. |
If
considered as the outcrop area of the Ragleth Tuffs then Ragleth Hill
forms an elongate ridge running SW to NE for some 1.65 km; reaching an
altitude of 398 m AOD (1305 feet). The maximum width of the outcrop of
tuffs is approx. 500 m and covers an area of approx. 0.75 sq. km.
Geological boundaries are the Ordovician Harnage Shales to the SE mapped
as faulted by BGS and the basal Longmyndian Helmeth Grits to the NW
mapped as an unconformity by BGS (Greig et al.; 1968) although
considered to be ‘stratigraphically insignificant’ by Cobbold & Whittard
(1935) and even conformable by Pauley (1991). It can be noted that both
boundaries follow a change of slope; for the Ordovician this is a sharp
lessening of angle from hillside to cultivated field but for the Helmeth
Grit there is a pronounced increase in slope angle on entering Ragleth
Wood particularly at the southern end. The hill could be taken as
providing the type section for the Ragleth Tuffs but there is a general
sparsity of exposure and better more definite sections of the tuffs are
to be found along the SW ridge of Caer Caradoc. In fact the major
outcrops amount to only four in number with positions as marked on the
attached map and there labeled A to D. (A) On the northern slopes of
the hill this is discontinuous sequence of exposures all lying along a
south trending strike for 120 m from SO4584 9259 to SO4582 9248.
Outcrop is of a roughly bedded tuff similar to that of 3-Fingers Rock on
Caradoc. Bedding is particularly obvious at the lattermost NGR where the
outcrop is of a 4 to 5 m high face dipping ESE at 75°. Polished surface
(slabbing) shows a fine pale and dark banding and confirms that the
visible texture is one of true bedding. (B) There is a complementary
outcrop on the southern slopes which forms a prominent step-like feature
clearly visible from the A49. Up to 3 m high this step extends for 100 m
from SO4504 9163 to SO4494 9159 with a discernible N-S strike cutting
across the feature with dips variable either side of the vertical. There
is some evidence that this feature is truncated by faulting at its NE
end. (C) The south west end of the hill offers an area of scattered
outcrops which appear to have been subject to quarrying or excavation in
the distant past. Among these at SO4490 9170 is an in situ exposure of
conspicuous near brick red rhyolitic tuff (?) at the end of a feature
which appears to dip 60° NW. This has significance as it is conformable
with some dips in the Helmeth Grit and with the regional dip of the
Longmyndian. (D) This small crag of coarse massively bedded tuff seems
connected to A with an apparent dip of 80° SE. The rock itself deserves
comment: polished surfaces show a granitic composition with equi-sized
grains of angular pink felspar; angular and rounded grains of
transparent quartz and irregular grains of biotite mica. That it is not
a granite is show by: a) freely fractured surfaces show the quartz as
perfectly formed clear pinacoid crystals; b) there are occasional
fragments of alien rock; typically a purple shale. Thus the rock is to
be classed as a ‘crystal-lithic tuff’ which has undergone free growth
and/or recrystallisation of the quartz (silification). (E) Around the
summit pole at SO4509 9176 are several rhyolitic blocks some or all of
which are not in situ. A few metres to the NW a genuine in situ
exposure appears to show a dip to the NW. In spite of sparsity of
outcrops; Ragleth Hill offers some scope for an itinerary; especially if
combined with exposures of Helmeth Grit in Ragleth Wood (q.v.). A
possible route is shown on the attached sketch map and starts from the
top of Poplar Drive (off Chelmick Avenue) at SO4585 9300. It
deliberately avoids the barren footpath along the ridge taking instead a
lower path on the SE flank which provides an improved view both of the
change on slope at the Ordovician boundary (not visible from the ridge
path) and the development of scarp features in the succeeding Ordovician
and Silurian sediments. There are a number of further outcrops around
this traverse which supplement those of A; B & C. |
Open access to the whole area via public footpaths |
LGS Yes. A major locality in determining the exact nature of the
Precambrian transition from a predominantly volcanic to a sedimentary
environment (especially when taken in conjunction with the Helmeth Grit
of Ragleth Wood). Good exercise in recognition of bedding and
appreciation of mapping problems and techniques. Significant in the
context of Uriconian to Longmyndian (volcanic to sedimentary)
transitions. Widespread views from itinerary traverse and even more so
from summit footpath. |
Mineralogy/Petrology |
| 1310 |
SO 446 916 to SO 458 927 |
Ragleth Wood - Church
Stretton |
Natural exposure |
Precambrian: Longmyndian: Stretton Shale Series: Helmeth Grit Member |
Scree and rock outcrops with at least one small patch of fluvio-glacial
debris |
The linear outcrop of Helmeth Grit lies between the slopes of the NE
flank of Ragleth Hill where it has a length of 1.75 km between SO446916
and SO458927 and maximum (horizontal) width of 100 metres. Its
geological boundaries are apparently conformable to the overlying
Stretton Shales but debatable to the underlying Uriconian Volcanic
Ragleth Tuffs. The outcrop is wholly covered by woodland - Ragleth Wood
- whose edges roughly correspond to the geological boundaries. However
these are more accurately placed by changes of slope there being a
general steepening of gradient in passing from the Ragleth Tuffs and a
lessening in passage to the Stretton Shale lithology. In the southern
part there is extensive scree clearly felt as lying just beneath the
very thin soil surface. Whilst the Helmeth Grit was recognised as having
a distinctive lithology by the Geological Survey (Greig et al.; 1968)
surprisingly no specific description of what this lithology is was
given; the memoir choosing to rely entirely on the descriptions given
earlier by Cobbold & Whittard (1935). From a now obscured section in
Hazler Road; Church Stretton; a natural outcrop in Ragleth Wood and an
excavation in ‘the triangular field abutting against the SW end of
Ragleth Wood’ these authors described the Helmeth Grits as an
interbedded sequence of four ‘Grit bands with somewhat variable shales
to a total thickness of 98 feet (30 m). From petrographic work they
concluded that ‘the rocks are .. lithic tuffs formed .. from already
consolidated Uriconian types .. and may be taken to represent the
decadent phases of the vulcanicity of the Uriconian’. The absence from
the memoir (Greig et al.; 1968) and from the paper of Pauley (1991) of
any mention of specific outcrops of the Helmeth Grit suggested that no
worthwhile outcrops remain. Nevertheless; difficult but persistent
exploration of Ragleth Wood has revealed at least four outcrops of a
nature to allow for construction of a large part of the sequence. Rock
samples recovered from these outcrops tend to confirm the findings of
Cobbold & Whittard but show; if anything; an even wider variety of
volcanigenic type. The position of four outcrops are indicated by
letters A to D on the attached map and each is given an identifying name
in the follow descriptions: (A) Original Quarry at SO4494 9224; closest
to the overlying Stretton Shales this shows a massively bedded arkose
like sandstone which has undergone deep weathering of its mafic (?)
minerals so that it now presents a quite porous texture. Unweathered
examples of apparently the same rock type have been recovered from other
exposures (including Ragleth Hill itself) and show an essentially
granitic composition of quartz; feldspar and mafics. Weathered pieces
are common throughout the whole outcrop (even on Helmeth Hill) and show
a pale brown/yellow gritty texture that seems to represent the so-called
‘distinctive lithology’ of Greig et al (1968). Note that it was this
quarry which was the subject of a LGS designation in 1997. (B)
Charcoal Ridge SO4489 9221; so-named as lying below a charcoal burner's
platform at SO4496 9218 (confirmed by presence of charcoal fragments in
the sub-soil). This is a steep narrow (5 m) outcrop some 25 m long;
forming a ridge of rock which is strongly jointed. There are also
further exposures on the left-hand (NE) flank. Overall the impression is
of a lithology similar to the Original Quarry but sampling (followed by
slabbing) shows a wide range of rock type including lithic tuffs with an
arkose matrix; pale grey brecciated rhyolite; dark gray basalt like
(lavas?); dark grey brecciated shales; mixed crystal (felspar and mafic)
and dark grey lithic tuffs etc. Whilst a sedimentary log would appear
feasible it seems likely that the outcrop is much broken by faulting and
hence presents a juxtaposition of various rock types. (C) Yew Tree Crag
SO4489 9206 (top) to SO4486 9206 (base). Whilst the ground hereabouts
is cut by deep gullies with seperating steep ridges this 30 m square
outcrop; overshadowed as it is by a large conspicuous yew tree; is of
great importance since it is the only location where dip direction and
magnitude can be unequivocally measured. This is because the outcrop is
of a large bedding plane of ‘grit’ overlain in its lower part by a thick
bed of apparently black ‘shale’. On slabbing the latter is seen to be
finely banded in shades of gray between pale and near black. There are
also interbedded thin 5 mm thick layers of arkose sandstone which
probably represent the ‘sandy shales’ of Cobbold & Whittard (1935). The
latter plus the grit bedding planes confirm a dip to the NW (65° to 310)
conformable with the regional dip of the Longmyndian from Stretton
Shales upward. (D) South-west Gully SO44829184. This is the locality of
Cobbold's excavation in the ‘triangular field’. The gulley marks a SW
boundary for the wood and was the line of the old walker's route up
Ragleth Hill starting from the A49 opposite the lane from Little
Stretton. It is steep boulder filled and awkward. At the top the angle
eases and there are outcrops on the right but a larger main outcrop just
in the woodland on the right. There is no obvious sign of what or where
Cobbold's excavation may have been. Both outcrops provide rock types
similar to what has already been mentioned but without giving clear
indications of dip and strike directions. Here would appear to be the
nearest exposures to the underlying Ragleth Tuffs - indeed Cobbold
stated; by a curious piece of circular reasoning; that his excavation
revealed the actual junction. This cannot be claimed now. Between SW
Gulley and Yew Tree Crag the ground is much covered by scree deriving
from a number of small outcrops that have not (yet) been investigated.
Ragleth Wood provides a relevant continuation of an itinerary which
begins by examining Ragleth Hill (q.v.). The route shown on sketch map
would reverse the sequence from SW Gully to the original quarry and then
follow a path around the lower edge of the wood to complete a circuit
back to a starting point in Poplar Drive. This lower path crosses at
least one on the traverse faults which overall affect the outcrop. |
Ragleth Wood seems open both from the slopes of Ragleth Hill
particularly by one or two very visible footpaths or from a path which
follows the lowermost boundary of the wood from vicinity of Snatchfields
at least to locality A. |
LGS Yes. Provides good in situ exposures of the Helmeth Grit which
support claims of vulcanicity continuing (although perhaps waning) into
the Longmyndian sedimentary regime. Good exercise in identification of
volcanigenic rock examples. Critical exposures in any consideration of
the Uriconian to Longmyndian transition. |
Mineralogy/Petrology |
| 1311 |
SO 2950 9785 to SO 2966 9805 |
Cwm Dingle (ridge) -
Priestweston |
Natural exposure |
Ordovician: Llanvirn Series: Weston Flags Formation: Upper Sandstone
Member. Upper Grit horizon within Weston Member of Middleton Formation (Whittard
& Dean; 1979) |
Although resembling an escarpment; the high angle of dip (c. 60°)
suggests the notation ‘reversed scarp’ (see attached diagram & note) |
The ridge is the outcrop of the upper ‘Sandstone’ within the Weston Beds
and forms the NW side of the hollow of Cwm Dingle (the lower sandstone;
100 m to the SE; forms the opposite side). The visible rock outcrop
extends for 300 m forming an ascending ‘edge’ running from SW to NE
along the regional strike direction. Dip is to the NW at about 60°. A
path climbs the edge from the SW and shows strong joint planes;
orthogonal to the bedding; overlooking the dingle to the right forming a
pronounced step or ‘scarp’. To the left the surface is relatively
horizontal so that bedding planes are not exposed except in the numerous
small quarried areas which have been worked on this side. It is this
seeming reversal of the role of bedding and joints which prompts the
appellation ‘reversed scarp’ for this topographic feature. BGS (1991)
describes the Weston Flags Formation as bioturbated sandstones and
siltstones. Whittard considers the Weston Member as being ill-sorted
shallow water deposits; possibly estuarine; varying from rough bedded
argillaceous strata to (smoothly bedded) massive units (Whittard &
Dean;1979; pp38-39). Along the ridge where the bedding can be seen it
shows an interbedding of thin rough flags and thicker smoother massive
beds. There is an abundance of talus derived from shallow quarry
workings to the left of the edge whereby both types may be examined. The
general grade is coarse siltstone to fine sandstone. Some beds occur
typically as 10 mm thick flags showing fine laminations and with
surfaces much roughened by two agencies. One is the effect of
bioturbation which in some pieces can be seen to have left vertical
burrows filled with light sediment which erupt onto and roughen the
surface and also locally destroy the lamination. Occasional bedding
planes can be found criss-crossed by the casts of ‘worm tubes’; termed
fucoid markings by Whittard. The second effect is that of sole markings
which also seem more organic than physical in origin. The massive beds
occur as smooth surfaced flags typically 30 to 50 mm thick. These can
vary from relatively soft olive and brown siltstone showing planar
laminations to hard; near black and rough fracturing units. Some
original calcareous content is suspected with much decalcification
present. A useful adjunct of this site is that; by choice of access
route; it may be better placed in the context of adjacent sediments of
the Weston Formation. Specific localities which can examined by a
recommended route are listed in an attachment. |
A
network of footpaths surround Cwm Dingle. Most direct access is by path
heading NE from Priestweston. A more convoluted route starts from a
layby at SO298977 near the summit of the White Grit road. This uses an
old road to Priestweston (now a green lane) and encompasses some half
dozen or so related localities. Details are in the attachment. |
LGS Yes. A wealth of sedimentary and bioturbation features combined
with a notable topographic feature demonstrably related to the
underlying strata. An excellent location for examination of bioturbation
and waning current sedimentary features combined with an impressive and
intriguing geomorphological feature. Has relevance to the deposition
conditions of the Weston Flags Formation. Some local use of the flags
for building stones. |
Sedimentology/Stratigraphy |
| 1313 |
SJ 754 034 |
Grindle Forge - Ryton |
Cliff |
Permo-Triassic: Sherwood Sandstone Formation: Kidderminster Conglomerate
and Bridgnorth Sandstone (Toghill). Sheet 153 has old nomenclature. |
Part of steep escarpment along Wesley Brook. |
An
excellent exposure of the transition between Bridgnorth Sandstone and
Kidderminster Conglomerate. 80 m of rock are exposed parallel to the
Wesley Brook reaching a height of 8 m. There seems to be an overall
easterly dip but the whole face shows impressive cross-stratification;
both small and large scale with overlapping units. A recess causes
overhang at the base which on closer inspection coincides with 200 mm of
red marl with sandstone below. Mottling is random but mostly seen
half-way up the face. About 8 m to the east swirling structures can be
seen and two thin 30 mm horizons of finely laminated shaly marl;
horizontally bedded some of which is grey-green. A great deal of small
sedimentary detail can be seen including alternating sandstone/marl
layers 2 mm thick. Approx. 30 m from the bridge another major face
shows a small fault which faults out the marl and where displacement is
discernible. Another interesting sedimentary feature is the slumping of
sandstone blocks into the underlying marl resulting in an irregular
sandstone base. It is difficult to identify a boundary between
Bridgnorth Sandstone and the overlying Pebble Beds but scattered small
pebbles make an appearance about two-thirds up the face. |
Open access by the road and beside the brook. |
LGS Yes. Designation because the sedimentary detail displayed here at
the junction between Bridgnorth Sandstone and Kidderminster Conglomerate
offers much opportunity for interpretation and reconstruction of palaeo-environments
during the Permo-Trias. Also it is an excellent site for groups for
teaching. |
Sedimentology/Stratigraphy |
| 1314 |
SJ 765 015 |
Old Rectory - Beckbury |
Track/roadside |
Triassic: Sherwood Sandstone Formation: Helsby Sandstone (new
nomenclature; Toghill). Old nomenclature on Sheet 153. |
The road cutting is part of the prominent escarpment formed by this
rock. |
The exposure on the east side of the road into Beckbury is about 50 m
long and shows up to 3 m of calcareous marl conglomerate with pebbly
sandstones similar to those at Badger Dingle. At the base of the
sequence are fairly massive sandstones with distinct cross-bedding.
These are finely laminated and display multi-directional
cross-stratification. Pebbles present in the sandstone are themselves
aligned to the cross-stratification; they are varied in size averaging
50 mm but the occasional pebble is 100 mm. They tend to form thin layers
and are generally dipping at about 20°. Pebble density is greater
towards the base of the sequence and the shape is mostly angular
although there is some rounding. Thin lenses of red/brown marl are
distributed throughout the rock and generally form cavities. However
approx. 400 mm from the base and 10 m from the old rectory gate is a
prominent recess of marl which can be easily examined. The whole
exposure is full of holes where pebbles have been weathered out. High up
at the old rectory end the sandstone appears to show evidence of
possible channelling. The rock has clearly been used for building in the
village and the stone walls contain interesting specimens. A collection
of varied loose rocks has been assembled beside the restored trough
outside the village hall and includes fine examples of Pentamerus
Limestone the source of which is a puzzle! |
Conveniently beside a public road. |
LGS Yes. Designation because it is a very good exposure of Helsby
Sandstone demonstrating a fluvial environment of deposition with varying
energy levels. It is one of few such exposures in the area. |
Sedimentology/Stratigraphy |
| 1315 |
SJ 7515 0575 |
Brimstree Hill - Shifnal |
Cutting (road/railway) |
Permo-Trias: Bridgnorth Sandstone and Kidderminster Conglomerate (Toghill);
from Sheet 153 which uses old nomenclature. |
The rocks here forms a hill. |
At
Brimstree Hill weak cross-bedded Bridgnorth Sandstone is capped by much
stronger conglomerate and is exposed effectively at the roadside. Up to
2 m of large-scale overlapping units are seen wedging out in different
directions. The rock is a uniform red millet seed-type sandstone typical
of wind-blown dune formation found in the Bridgnorth area. The units are
finely laminated and mottled in places. There is a very definite
boundary with the Kidderminster Conglomerate which appears to dip
towards the south-west at about 10°. Pebbles are small aligned in thin
layers reflecting the cross-bedding. Pebble beds reach ground level at
the southern end of the cutting which extends for about 40 m. This cap
of conglomerate is very hard and the pebbles are held in a strong
purple/brown sandy matrix. This can be compared with the outstanding
site at the Hermitage in Bridgnorth. |
Open access by the roadside. |
LGS Yes. Designation because the exposure clearly shows the boundary
between the two contrasting rock formations (Bridgnorth Sandstone and
Kidderminster Conglomerate) which in turn reflect contrasting former
environments of deposition. |
Sedimentology/Stratigraphy |
| 1318 |
SJ 549 268 |
Lee Brockhurst (rock
cutting) |
Track/roadside |
Triassic: Sherwood Sandstone Formation: Wildmoor Sandstone (Toghill).
Sheet 138 has old nomenclature. |
The f3 Formation; Wildmoor Sandstone; here forms a prominent hill; into
the edge of which an old lane was cut. |
Each side of the path are 4-5 m high vertical exposures of cross-bedded;
red soft sandstone. The exposure continues for at least 100 m and is
easy to examine and in good condition. Beige patches form the mottled
effect which gave this the former name of Upper Mottled Sandstone. The
cross stratification is impressive and multi-directional; with varied
angles of dip. The texture of the orange-red sandstone is fine and
well-sorted with no pebbles. However; there are horizons where the
quartz grains are coarser and apparently of the millet seed type. The
exposure shows much vertical jointing and several faults; there is one
excellent example of a fault plane with a trend of 120° which crosses
the lane; able to be linked up as it continues on the other side.
Slickensiding is visible and there is slight mineralisation. The strata
consist of blocks; often having slipped and giving a chaotic appearance;
but there is a tendency for the layers to become finer towards the top
of the exposure. |
Easy access via a public right of way. |
LGS Yes. Designation along with the sites referred to in LGS report SJ
547268. Together these sites provide opportunity to examine Triassic
exposures which display a range of textural; and structural features. |
Sedimentology/Stratigraphy |
| 1319 |
SJ 548 267 |
Lee Brockhurst (river
bridge) |
Cliff |
Triassic: Sherwood Sandstone Formation: Chester Pebble Beds (Toghill).
Sheet 138 with old nomenclature. |
Steep cliff by the R. Roden. |
An
exposure; up to 4 m high; extends for 25 m from the bridge. The whole
appearance is one of disturbed bedding produced by shifting currents.
The sandstone is coarser than Wildmoor Sandstone and a browner red in
colour. This is near the top of the Chester Pebble Beds. Pebbles are
scattered throughout the rock; being mainly angular and small (20 mm)
but there are pockets of more densely packed pebbles within the
sandstone. The strata are distinctly cross-bedded; some small scale;
others larger and in places very disturbed. There is much to suggest a
relatively high energy environment. Circular patches of softer sandstone
occur with iron compounds forming rims which stand proud from the softer
rock. Elsewhere; swirling structures are seen in the sandstone. Evidence
of small scale faulting occurs and there is a much more distinctive
fault with trend of 200°; displaying slickensided surfaces and
mineralisation. Along the fault plane is a gap of 300 mm occupied by a
fallen block with a second fault a metre or so to the west; its trend
being 160°. This is a very interesting site when seen in the context of
the other sites at Lee Brockhurst. The face at this river cliff appears
to be the actual place where the major east/west fault crosses the road. |
Via a non-public but well-used path to the river under the road bridge. |
LGS Yes. Designation because it is an easily accessible large
informative exposure of Upper Chester Pebble Beds which provides
evidence for palaeo-environmental reconstruction situated where a
faulted junction of f2 f3 and f6a occur. The river cliff forms a major
E-W fault. |
Sedimentology/Stratigraphy |
| 1321 |
SJ 560 286 |
Wixhill Lane - Weston under
Redcastle |
Track/roadside |
Triassic: Sherwood Sandstone Formation: Wildmoor Sandstone (f3). Sheet
138 uses old nomenclature. |
North-west edge of the sandstone hilly area around Weston. |
Exposures here occur along a large part of the lane leading from the A49
to Wixhill village. Exposures consist of overall near horizontal bright
red sandstone within which is low angle fine cross stratification. The
partings are wavy between the thin; hard beds and there is an appearance
of rippling and a scalloped effect. The height of the exposure is about
3 m. One horizon; approx. 2 m up; and 30 mm thick; is noticeably
recessed. The rock is heavily jointed; some curved and parallel;
especially towards the village and under a garden wall on the south
side; some of these show slight displacement suggesting they may be
small faults. On the south side there is more massive bedding (up to 1.5
m thick) often with a definite boundary where the latter are overlain by
softer cross-bedded strata. |
Easy roadside access. |
LGS Yes. Designation suggested because it is an extensive exposure of
the Wildmoor Sandstone with interesting sedimentary and tectonic
structures close to a significant fault zone. |
Structure and Sedimentology/Stratigraphy |
| 1323 |
SJ 594 289 |
Marchamley - Hodnet |
Quarry (disused) |
Triassic: Sherwood Sandstone Formation: Helsby Sandstone; and Mercia
Mudstone Formation: Tarporley Siltstones. Sheet 138. |
Southern edge of sandstone escarpment which borders Hawkstone Park. |
This report covers two adjacent sites. The Quarry: This disused quarry
is easily seen by the roadside and the massive white sandstone is
striking. The rock is soft yet stands up as a near vertical face. There
is evidence of large-scale cross-bedding. The texture is mainly uniform;
the clean quartz grains giving the appearance of beach sand. However; a
few quartz pebbles (20 mm across) were present; as were scattered
harder nodules; possibly of barytes-rich sand. In the westerly corner of
the quarry; there is a fault line and the light colour of the rock
changes to red. Another interesting feature at this end is what appears
to be barytes cement which produces a ridged effect; outlining the
cross-beds. There are also diagonal cross joints at angles of 120° and
060°. At the easterly end; the boundary between f5 (Helsby Sandstone)
and f6 (Tarporley Siltstones) can clearly be seen. The red and grey
coloration contrasts with the white sandstone beneath. The Tarporley
Siltstones are dipping gently NNE and occupy the top 2 m or so. The
lowest 750 mm comprise an esk bed; i.e. grey shaly sand with specks of
manganese dioxide; and this is succeeded by red flaggy sandstones. A
noticeable infilled joint or even a fault; cuts through the strata here;
widening at the bottom. It is filled with light; soft sandstone and is
0.5 m across. At the top of the succession; the grey esk bed thickens
and has collapsed into the joint/fault to fill it. The lane south from
Marchamley: The Tarporley Sandstones and Siltstones continue up the
hill and it is possible to walk up through the sequence which is
described in detail by Pocock in the Wem Memoir. There is a section off
the road on the west side where the strata is weathering purple/brown
and is near horizontal. Red and grey sandy mudstones are very thinly
bedded; only millimetres thick and a distinct micaceous sheen can be
seen along the partings. The exposure here is 3 m high and 15 m long;
showing alternation of harder and softer beds and the resultant
differential erosion. The harder beds are more iron-rich. Fallen blocks
give good opportunity to examine fresh rock samples. In some sandstone
horizons pellets of mudstone are present. As one goes up the hill;
thicker sometimes mottled; mudstone layers are seen up to 750 mm thick
which are usually recessed below poriferous sandstone. Indeed the whole
of this road section consists of alternating harder and softer horizons
within the Tarporley Siltstones. There is clearly scope for detailed
stratigraphical study here. |
Both the quarry and roadside exposures are readily accessible. |
LGS Yes. Designation because the site demonstrates stratigraphical
detail at the boundary between Helsby Sandstone and Tarporley Siltstones
and allows close examination of sedimentary succession; structures and
facies change. |
Sedimentology/Stratigraphy |
| 1324 |
SJ 496 242 to SJ 496 247 |
Bilmarsh Lane - Middle and
Broughton |
Track/roadside |
Triassic: Mercia Mudstone Formation: Mercia Mudstone (Keuper Marl).
Sheet 138. |
Lane cut through Mercia Mudstone on N-facing slope. |
Mercia Mudstone is exposed for about 750 m on both sides of a lane; now
a bridle path. At the southern end; slightly micaceous red mudstone
occurs on each side. The rock is crumbly and there are thin broken
layers of harder; sandier mudsone alternating with more argillaceous
material. On the day visited; water washed over flat 'steps'; harder
sandstone bands; in the path. Very thin soft beds are overlain by a
metre of the harder; sandy mudstones; each bed about 40 mm thick; and
dipping at less than 5° NW. The exposures improve northwards with
mudstone broken into small; rectilinear blocks on an otherwise massive
face with more sandstone on top. The mudstone is partly fissile and the
harder bands are said by Pocock to be ‘poriferous’. Certainly small
holes were seen in these horizons as were carbon fragments. There are
many joints and several small faults with minor displacement. At the
northerly end; exposures are higher; being up to 4 m on both sides of
the path; showing at least one good flat joint plane and sandstone
layers up to 100 mm thick. The extent and condition of this exposure is
the result of the presence of the alternating sandier; more resistant
horizons. |
Public bridleway from Alderton. |
LGS Yes. Designation because exposures of Mercia Mudstone are few and
this demonstrates the characteristics of the Formation very well. |
Sedimentology/Stratigraphy |
| 1325 |
SJ 360 139 |
Old Quarries - Loton Park -
Alberbury |
Quarry (disused) |
Lower Permian: Alberbury Breccia ( see P. Toghill). Formerly classified
as Upper Carboniferous. |
Because of the relative hardness of this rock the … (entry incomplete) |
At
the north end of the quarries there is an impressive face up to 8 m
high. Seen from a distance of 3 m the face looks massive and is
vertical; having a red/brown sandy appearance. On closer examination;
there is evidence of thin bedding and there is an apparent dip of about
15° NE. Large; sub-angular and sub-rounded fragments; many of them grey
in colour occur at particular horizons. Many of the fragments are
limestone and the presence of Lower Carboniferous fossils; e.g.
Lithostrotion corals and crinoids; support the opinion that the source
of these is Llanymynech Hill which lies a short distance to the west.
There are also noticeable fragments of a more porcellaneous micritic
limestone found in the same vicinity. Textures vary a great deal; some
horizons being very fine; others much coarser. There is also evidence of
cross-bedding reflected in the fragment pattern in the rock. One
interesting structural feature is what appears to be a chimney-like
joint tapering towards the bottom; with infilling of unsorted material;
roughly aligned ranging from fine marl to coarser sand and breccia. Just
round the corner in the same quarry is soft; mottled red/yellow
crumbling material which has accumulated around the harder rock as if it
has slipped and filled in available spaces. Some of the strata are thick
and containing large fragments on the base of the beds. Good examples of
grading can be seen. Differential erosion brings out variation in
hardness between the beds. Further to the SW; above and beyond the lake;
are many other exposures. One of these lies below the Deer Park wall and
consists of a 3 m high; rather weathered face extending for about 10 m.
There are very large limestone fragments visible in the breccia; some
over 200 mm across; which in places demonstrate some alignment. One sees
a jumble of mixed fragments including sandstone; quartz; marly pellets
and crinoidal limestone. The matrix is calcareous and at times marly;
there are also cavities formed by the dissolving out of the limy matrix.
Close by there is an old limekiln; beautifully made and preserved;
consisting of the Alberbury Breccia. Small stalactites of limy deposits
occur on the roof. Throughout the Park the textures of the breccia are
fascinating and would repay serious study. |
Some of the exposures can be seen from public footpaths but for more
detailed study permission needs to be given by Sir Michael Leighton. |
LGS Yes. Designation because the Alberbury Breccia is unique and here
are excellent exposures which provide opportunity for textural studies
and palaeo-environmental reconstruction. |
Sedimentology/Stratigraphy |
| 1326 |
SJ 364 132 |
Loton Deer Park - Alberbury |
Cutting (road/railway) |
Lower Permian: Alberbury Breccia (Toghill). No geological map. Formerly
classified as Upper Carboniferous. |
The highest sandstone of the underlying Keele Beds forms a bold
escarpment in the west of the Deer Park and this exposure is cut into
the lower beds of the Alberbury Breccia east of the top of the ridge. |
A
good exposure on both sides of the track. The rock is up to 3 m high and
displays regular stratification. These beds are at a lower horizon
compared with those of the old quarries described in LGS report SJ
360139 and contain smaller fragments on the whole. The appearance of the
beds here is distinctly flaggy with even partings. Dip seems to be at
18° NE. The strata are only about 30 mm thick at the top of the exposure
but reach 150 mm nearer the base. The stratification is not consistently
regular; there being irregular blocks; even a rounded one on the north
side. The faces which are broken by jointing; are quite badly weathered
in places and textural detail is less good compared with the faces in
the old quarries. At the sides of the footpath north of this site; Army
activity dating from the Second World War has left many loose blocks of
breccia which can be examined and there is a series of small rectilinear
quarries along here which demonstrate a great variety of textures and
are of a convenient size for close up study. Here the dip is about 10°
roughly northerly in direction. Examination of true and apparent dip can
be carried out effectively in these small quarries. |
Easy access from footpaths but permission should first be sought from
Sir Michael Leighton; Loton Park Estate. |
LGS Yes. Designation because the horizons in the cutting lie beneath
the exposures in the old quarries and the two sites together give a more
complete picture of the Formation as a whole. |
Sedimentology/Stratigraphy |
| 1327 |
SJ 561 287 |
Wixhill Farm - Weston under
Redcastle |
Mine/adit |
Triassic: Sherwood Sandstone Formation: Wildmoor Sandstone (f3) (Toghill).
Sheet 138 uses old nomenclature |
Line of fault can be seen in separated exposures standing up abruptly in
a NNE/SSW direction. It forms the edge of the higher sandstone terrain. |
An
exposed fault plane along the line of the Brockhurst Fault at Wixhill
where copper ore was worked from 1865-67. No real evidence of the copper
ore was seen but the fault plane shows slickensiding and alteration of
the Wildmoor Sandstone which here is harder and shows no cross-bedding.
The exposure is 2 m high and a black mineral is present on the surface;
probably manganese oxide. A few metres to the NE behind some vegetation;
an exposure across the fault zone is present. On the right;
near-horizontal thinly bedded strata suddenly become a vertical fault
zone; broken and curving in places. Thin parallel veins of barytes;
10-20 mm wide occur within the fault structure. The altered sandstone is
grey/pink/purple in colour and the most heavily mineralised patch is at
the left-hand bottom corner of the exposure. Through the gate on the
public footpath; a small old quarry is seen; its rock surfaces very
badly weathered; but the face is vertical and it is clearly a
continuation of the fault plane. From the lane which leads to the main
road 'The Mount' is visible; marking the position of the fault line;
here the Mercia Mudstones are faulted against the Tarporley Siltstones. |
Very close to a public footpath which goes through a seemingly disused
farmyard. |
LGS Yes. Designation because this is an excellent exposure of part of
the Brockhurst Fault and associated features along which copper was
formerly mined |
Mineralogy/Petrology |
| 1328 |
SO 4415 9492 to SO 4434 9518 |
The Pike - Cardingmill -
Church Stretton |
Bank |
Precambrian: Longmyndian: Stretton Series: Synalds Group |
A
fine erosional feature of steeply dipping beds forming a hogs back ridge |
The ridges of ‘The Pike’ rise immediately from the NE side of the valley
road and seem precisely aligned to the local strike of N030E. The
longest extends for 430 m and the altitude of the crest increases from
225 m to 375 m AOD - an average gradient of about 1 in 3 so quite steep.
Dip is consistently to the NW but angle varies between 60° and vertical.
The ridges present an interesting case of development of a hogs back
feature when the dip significantly exceeds 45°. Retaining a hogs back
terminology then the scarp slopes face SE but its slope angle cuts
across the bedding and this is where most of the rock exposures occur.
The dip slope faces NW but little rock is exposed and the general
tendency is also for the slope to cut across the bedding. Above a
junction 175 m from the road the stream runs between the ridges and is
so deeply incised in parts as to be an object lesson in ‘gulley
erosion’. Above the stream junction it has cut through several metres
of drift into underlying bedrock. The Pike was selected as a GCR site
‘because it contains one the most informative and well exposed sections
through the Synalds Formation’. Three localities are identified for
description (Wilson 2001) and all are easily accessible via the stream
which delimits the SE boundary of the exposures (see sketch map). This
survey confirms that all the features of this description are present
and readily recognisable. In particular:alternations of sandstone; often
coarse; with siltstone & mudstone; a very conspicuous cleavage is
developed in the finer grained purple silt and mudstones; visible
lamination is planar or gently undulating; occasional thick massive beds
of sandstone occur; typically 0.5 metres thick; basal sandstone surfaces
can be weakly erosional cutting into underlying silt or mudstones.
Differential erosion as between sand and mudstone is strongly developed;
especially at locality 1 Samples collected for ‘slabbing’ show that
sedimentary textures are perhaps more strongly developed than the GCR
descriptions suggest. Coarse sandstone is only weakly graded but finer
sandstone is notably admixed with layers of purple siltstone/mudstone in
a variety of laminations and banding which can be markedly undulose;
e.g. ripple or ripple drift lamination. Apparently homogenous purple
mudstone can show quite strong convolute lamination. The alternations of
beds is suggestive of turbidites and; for example; bedding surfaces of
the purple mudstones are usually grooved and fluted and sometimes
scalloped; although the latter seems to be an effect of interaction
between minor slippage and bedding. It is on these surfaces that pit
markings are common and examples interpreted as ‘rain-pits’ - although
looking more like ‘drizzle pits’ - are frequently found. Finally the
exposures at localities 1 and 2 (and elsewhere) are crossed by incipient
faults which produce effects demonstrating bedding competence; mudstones
become sharply bent developing an angular fold very similar to kink
banding whilst adjacent sandstones bend into gentle curves. |
Public access as part of Longmynd National Trust |
LGS Yes. Designated both as an interesting and very explicit Geomorphological feature as well as providing extensive and detail rich
sedimentary exposures. Really good exposures for sedimentary features
plus cleavage and some minor faulting/folding. |
Structure and Sedimentology/Stratigraphy |
| 1329 |
SJ 699 303 to 697 307 |
Cheswardine
Road Bridge (Cheswardine canal cutting) - Sutton upon Tern |
Cutting (road/railway) |
Triassic: Bunter Pebble Beds (Chester Pebble Beds) and Upper
Carboniferous: Keele Beds |
Man-made excavation |
Best exposure of Keele Beds is just SE of the High Bridge where dull
red/purple sandstone layers alternate with soft red marls. There are
apparently (see Whitehead; p.17) five principal sandstone layers in this
section; the thickest bed is up to 3 m. Sandstone layers are variable in
thickness and can be seen wedging out among the marls. Recesses mark the
position of marl horizons below projecting sandstone. Unfortunately the
marls are very overgrown and disintegrate into mud although red and
greenish horizons are apparent. They are noticeably fissile. Fallen
blocks of sandstone and marl are found on the towpath and allow
examination of fresh surfaces so that sedimentary structures e.g. ripple
bedding is evident. The dip is mostly gentle and there seems to be a
shallow anticlinal structure between High Bridge and a fault which
brings up the Chester Pebble Beds. Visibility was poor on the day of the
survey as fog shrouded the canal so the strata on the east side was not
easy to see! Between Cheswardine road bridge and a fault which crosses
the canal 100 m to the north; Chester Pebble Beds are exposed. It is not
easy to locate the exact position of the fault but the approximate
junction of Pebble Beds and Keele Formation can be found. The best
exposures of Pebble Beds occur closest to the fault where 5 m high
massive sandstone with pockets and layers of mostly quartzite pebbles
can be seen. The brown-red sandstone beds (with large scale
cross-bedding) are up to a metre thick and contain variable densities of
pebbles (some aligned with the cross-beds; others scattered randomly).
The pebbles show a range of sizes from a few millimetres to 150 mm
across mostly showing evidence of rounding. At the southern end the
beds are thinner (200-300 mm) and contain more pebbles. |
By
public towpath on the west side of canal. East side not easily reached. |
LGS Yes. Designation because this is considered the best available site
in the area for the Keele Formation and particularly well demonstrates
details of channel form enabling interpretation of Late Carboniferous
and early Permian geological history. |
Sedimentology/Stratigraphy |
| 1330 |
SJ 656 193 |
Shray Hill - Cherrington |
Quarry (disused) |
Permo-Trias: Chester Pebble Beds (close to f1/f2 boundary on Sheet 138) |
Pebble Beds form a hill. |
The front of the site is seen from the Newport/Shrewsbury road. The
exposure at the front has been used as a tip by the farmer and access to
the faces is not easy. However; a 5-6 m high exposure can be seen
showing red; cross-bedded sandstone with chaotic slumping on the right.
The dip is approx. NW. The beds vary in thickness and a scattering of
mostly sub-rounded quartz pebbles; max. length 50 mm; is visible. The
cross-bedded units are clearly seen and overlap. The best exposures are
found on the west side; and are reached from a lane and by crossing a
field. Here up to 8 m of massive red sandstone is present with thin
yellowish horizons. The top 1.5 m are thinner and display distinct cross
stratification. There is a very interesting infilled vertical structure
which seems to show slight displacement on the right; suggesting a fault
rather than a joint; and along the face are excellent examples of cross
stratification with opportunity to study 3-D deposition. The exposures
are close to base of the Pebble Beds and pebbles can be seen in the
sandstone at ground level. These are sub-rounded to sub-angular. The
site is very good for the study of sedimentary structures and there are
swirling; pseudo-folds and sweeping cross-beds mostly orientated from
right to left (south to north approx.). The site seems to suggest
deposition from fluvial processes. |
Not public but permission can be obtained. |
LGS Yes. Designation because this is an excellent example of fluvial
deposition in early 'Bunter' times with opportunity to study a range of
sedimentary structures and to reconstruct palaeo-environments. Important
for local building stone. |
Sedimentology/Stratigraphy |
| 1331 |
SJ 689 327 |
Tyrley Locks |
Cutting (road/railway) |
Permo-Trias: Lower Mottled (Bridgnorth) Sandstone and Bunter (Chester)
Pebble Beds. Sheet 139. |
Man-made excavation |
Clear strata can be seen in the canal cutting just north of the Tyrley
road bridge extending for a distance of at least 300 m. At the southern
end where the locks begin a bright red soft sandstone is exposed with no
discernible pebbles but displaying excellent cross-bedding with units
dipping at angles varying from 20° to 30°. There is one particularly
good saucer-shaped dune type unit 9 m across. These beds appear to be
wind-blown deposits consistent with the Permian desert facies of
Bridgnorth Sandstone. In places there is distinct yellowish mottling
including a thin 40 mm yellow horizon. There is a gradual change to
Chester Pebble Beds as thin layers of pebbles begin to appear above the
cross-bedded sandstone. Within the more massive sandstone beds is what
could be evidence of channelling suggesting a change to fluviatile
conditions. The pebble layers appear at the top of the exposure and dip
approx. N before reaching ground level. These layers are up to 250 mm
thick with scattered random pebbles of mixed sizes throughout the
sandstone at the northern end of the cutting. Sometimes the pebbles form
densely packed lenses. On the east side of the cutting similar strata
are also displayed but it is interesting to note that 0.5 m thick
sandstone beds; here nearly horizontal; occur opposite cross-bedded
pebbly layers and lenses. Max. height of the exposed strata is 4-5 m. |
Public canal towpath. |
LGS Yes. Designation because there are extensive easily accessible
exposures of Permo-Triassic strata useful for interpreting variation in
facies and providing a complementary sequence to that at Cheswardine
cutting. |
Sedimentology/Stratigraphy |
| 1332 |
SJ 714 194 |
The Rockhole - Edgmond |
Quarry (disused) |
Permo-Trias: Chester Pebble Beds. Sheet 139. |
Pebble Beds form higher ground in Edgmond (and in the area around).
Quarry is cut into the hill. |
This is a first rate large site which has many interesting features. The
rock is essentially a coarse red sandstone; distinctly bright where the
faces are fresh. Within it are scattered pebbles; mainly vein quartz and
quartzite. At the base of the main north face are thick beds a metre or
so in thickness. Above 2 m there is a marked change to cross-bedded
units; very well displayed. These are mostly low-angle; 10°-15° and
multi-directional; indicating shifting currents. Within the cross beds
the sandstone is finely laminated and contains more pebbles showing some
alignment. The boundary at 2 m is very definite. The pebbles are
sub-rounded to angular; maximum length being 70 mm. Because of recesses;
it is possible to see the cross-beds in 3-D which is useful for working
out palaeo-currents. At a height of about 5 m; at the top of the quarry
face; the strata become more thinly bedded with horizontal partings.
Both vertical and oblique joints are evident as are at least 3 faults
with displacement of 40-50 mm. On the south side is an interesting
irregular collapsed fault or joint where cross-beds have steeper dip. No
evidence of mineralisation or slickensided surfaces were found. Slump
structures and graded lamination can be identified in the sandstone. At
the east end of the quarry are two major recesses at two levels. These
appear to correspond with the presence of a dark red/brown fissile;
shaly marl containing mica flakes and finely bedded with horizontal
partings. At the higher horizon; the marl was up to 0.5 m thick. |
A
public footpath goes through and access to faces is excellent. |
LGS Yes. Designation because it is an impressive site in the Chester
Pebble Beds; large accessible and demonstrates a variety of sedimentary
structures besides providing opportunities for interpretation so that palaeo-environments can be reconstructed. |
Sedimentology/Stratigraphy |
| 1333 |
SO 767 994 |
Badger Dingle -
Badger |
Cliff |
Triassic: Sherwood Sandstone: Helsby Sandstone (Toghill) |
Deeply cut dingle in the Worfe valley. The Helsby Sandstone forms a
prominent escarpment in this area. |
There is a 5 m high cliff of coarse red sandstone with pebbles roughly
aligned within the massive horizon and finely bedded
cross-stratification at its base. Under this and recessed is a 300 mm
thick bed of red-brown calcareous marl which displays an arching
structure. In places the sand deposition has caused distortion of the
marl and swirls can be seen (see photo). The pebbles 40 mm max. length
are mixed with fragments of marl and are mostly angular in shape. This
is described as calcareous marl conglomerate. There are also thin
laminations of micaceous sandstone within the thicker beds. A little
further along the exposure to the west irregular pebbly bands alternate
with bright red purer weak sandstone with visible light quartz grains.
Several vertical joints (recessed and infilled) divide up the face and
there is possible faulting because the sandstone appears to have moved
and slumping is evident. Rock falls occur and loose blocks can be
examined at the foot of the cliff; these display interesting textures.
There are more exposures and interesting ornamental features e.g.
grottoes and caves in the rest of the dingle. |
Although the dingle is private a public footpath crosses it very close
to the exposure described. |
LGS Yes. Designation because it is a clear exposure of the calcareous
marl pebbly sandstone and various structural features representative of
the Helsby Sandstone Formation. |
Sedimentology/Stratigraphy |
| 1336 |
SJ 6710 3325 |
Walkmill Nature
Reserve |
Cliff |
Permo-Trias: Chester Pebble Beds. |
Part of a river cliff along the Tern. |
There is an exposure of massive cross-bedded sandstone about 4 m high
and 80 m long. The cross-bedding consists of large scale units with
sporadic pebbles. The first cliff section reached from the entrance is
rather disappointing because of the deterioration of faces obscured by
moss and vegetation; and detail is hard to see; although a pebbly layer
is seen at the base of the cliff. The section improves further along and
the bottom 1.5 m consists of a bed of randomly distributed pebbles
recessed below a thick sandstone unit. Pebbles can be seen along the
layers of the cross-beds. The sandstone is orange/red; showing fine
laminations and some graded bedding. The sedimentary structures are
interesting; particularly some 'folds' in the stratification which may
be a form of slump structure. The texture of the sandstone varies from
being coarse to much finer. |
By
public footpath in the nature reserve. |
LGS Yes. Designation because of its potential as an example of Chester
Pebble Beds within a SWT Reserve and is included on the Nature Trail
here. (A badger sett has been excavated in the sandstone) |
Sedimentology/Stratigraphy |
| 1337 |
SJ 472 068 and SJ 473 067 |
Lyth Hill |
Natural exposure |
Precambrian: Longmyndian: Wentnor Group: Bayston-Oakswood Formation.
Sheet 152. |
At
the top and bottom of the south-facing fault scarp of Lyth Hill. |
The conglomerate is exposed in a band down the hill; the best exposure
being at the top; near to the footpath. This is at SJ472068. Along the
footpath; parallel to the road; coarse conglomerate begins to appear 45
m before the main exposure. By the stile a large exposure is seen;
height 5 m. It has a smooth surface but is traversed by parallel pebble
bands projecting from the matrix in a N-S direction. These bands are
packed with pebbles; size ranging from a few mm to over 80 mm. Pebbles
are sub-rounded to sub angular and are of mixed composition but mainly
of quartzite and vein quartz with a few igneous ones. A few metres
further along; there is a sort of grotto with excellent conglomerate;
the distinct bands are not so obvious here but there is a possible fault
at this site with evidence of disturbance and some fragmentation of the
rock. This is the Stanbatch Conglomerate; displaced eastward by the Lyth
Hill Fault. Below this very good exposure; the conglomerate can be
traced down the hillside and at SJ 473067 another good but smaller
exposure can be examined. Here many rhyolitic pebbles were identified. |
Along public footpaths. |
LGS Yes. Designation because this is an excellent; accessible;
impressive example of the Stanbatch Conglomerate within the Wentnor
grits and sandstones. |
Sedimentology/Stratigraphy |
| 1338 |
SJ 315 139 |
Bulthy Car Park - Wollaston |
Natural exposure |
Ordovician: Caradoc Series: Breidden Volcanic Group: Bulthy Formation:
Bomb Rock. |
At
the foot of the northern-most end of Bulthy Hill; one of the volcanic
hills of the Breidden group (but in England!). |
Amazing large rounded boulders set in a massive face - one of those
'wow' sites! The boulders or 'bombs' are between 300 and 600 mm across
projecting from the matrix of tuff. The height of the face is about 3 m
and width of this particular face 7 m or so. At the top the 'bombs' are
densely packed while lower down; they are less so but moulds of the ones
that fell out are a distinct feature of the exposure. The 'bombs'
themselves are of andesitic tuff. To the right of this face there is a
fault showing slickensiding; brecciation and infilling. The matrix rock
is a grey; purple and granular; with small tuffaceous fragments and
shows clear stratification especially where the number of 'bombs' is
fewer. Near the west end of the quarry are major bedding planes up to 5
m high dipping at approx. 60°. Here; the rock is mainly tuff and there
appears to be a N-S trending fault; the plane dipping inwards at approx.
70°. The whole quarry is worth looking at and has great potential. |
The lane goes through and the quarry is used for parking. Easy public
access makes the site a very useful one. |
LGS Yes. Designation because there is nothing like this elsewhere in
Shropshire. The site admirably demonstrates an environment of explosive vulcanicity and deposition of a water-lain conglomerate in submarine
fans. Can be studied along with the related rocks of the Breiddens over
the border. Fairly recent work on this formation was done in 1986 by
Dixon. |
Mineralogy/Petrology |
| 1339 |
SJ 309 133 |
Bulthy Mine - Wollaston |
Mine/adit |
Ordovician: Caradoc Series: Breidden Volcanics: Bulthy Formation. No
geological map; refer to Toghill |
Off the path between Bulthy and Middletown Hills; SE side. |
There are several old mine shafts in the area and this one is clearly
along a fault. It is an excellent example of a fault with associated
features. Firstly; brecciated fragments form an encrusting layer on both
sides of the tunnel entrance; these vary in size from 150 mm across to
very small angular fragments. The rock type is an andesitic tuff.
Secondly there are slickensided surfaces and thirdly; much barytes
mineralisation. This forms an irregular vein 300-550 mm across. Going
into the mine entrance the mineralisation is seen to form the roof in
which barytes crystals are clearly visible. It was then realised that
the miners had been extracting barytes which had formed along the fault
as a substantial mineral vein. There were no signs of other minerals.
The tunnel rises at a steep gradient and can be entered to obtain better
views of the barytes crystallisation. This seems to be a significant
fault crossing between Middletown and Bulthy Hills. Along the footpath
are other overgrown tunnels and spoil with loose pieces of barytes
scattered around. |
Public footpath just on the Shropshire/Powys boundary so access is open
and easy. |
LGS Yes. Designation because this really is a magnificent fault in the Bulthy Formation with excellent associated features and a good example
of former mining on the border. |
Mineralogy/Petrology |
| 1340 |
SJ 415 055 and SJ 414 052 and SJ 416 054 |
Habberley Brook -
Pontesbury |
Stream/brook |
Precambrian: Longmyndian: Wentnor Formation: Bayston and Oakswood
Group. Sheet 152. |
Deeply cut narrow valley on east of Earl's Hill. |
The Lyd Hole is a spectacular site where a series of waterfalls; a chute
of water; and vertical sides of a gorge occur with a varied suite of
Uriconian volcanic rocks and Longmyndian sediments. Parts of the site
are too dangerous to allow close examination by many field workers;
indeed it was the present surveyer's 'assistant' who actually reached
the heart of the site! Even then; the rock surfaces are weathered;
obscured by algae and fresh rock samples not easily found. A pinkish
rock; probably rhyolite was seen and some rotten basalt; but the key
boundary remained elusive in view of the conditions. Above the
waterfalls there is; apparently; one of the few places in the Welsh
Borderland where a contact between Western Uriconian and Longmyndian
rocks is exposed. The presence of Uriconian fragments in the Longmyndian
sediments here is strong evidence that the Western Uriconian rocks
pre-date the Longmyndian. The junction is of considerable historical
interest; having been the subject of an intense controversy between a
number of researchers. Near to the Lyd Hole along the Habberley Brook
are three more exposures of interest. At the 'entrance' to the gorge the
rock is a distinct conglomerate; the Radlith Conglomerate; earliest of
the three bands of conglomerate in the Wentnor Series in this area; it
dips at about 60° ESE. Then back along the brook at SJ 416054; a very
good exposure of the Oakswood Conglomerate can be examined on the east
bank of the brook. Four metres are exposed and large; up to 120 mm;
densely packed pebbles occur with very little purple/red matrix. This is
the middle band of the three conglomerates; it dips steeply; again in an
approximate easterly direction. At SJ 414052 steeply dipping pebbly
grits (75°) with pebbles up to 10 mm are exposed along the footpath.
This is the fairly typical purple sandstone of the Longmyndian. Harder
bands alternate with softer; crumbling ones within which are 3 mm layers
of grey sediments. Calcite veining is evident in places. This is a good
exposure easily examined. |
The latter couple of sites are readily accessible as they are by the
footpath; but the Lyd Hole is difficult to reach especially when the
brook is high. Not to be recommended except for seriously fit
geologists! |
LGS Yes. Designation because of the SSSI designation and the importance
of the Uriconian/Longmyndian boundary and the use of this for
unravelling the Precambrian sequence. The assessment rating is very high
because of this despite the limitations of the Lyd Hole for general
educational use (only suitable for fit adults). |
Structure and Sedimentology/Stratigraphy |
| 1341 |
SJ 409 048 |
Earls Hill - Pontesbury |
Cliff |
Precambrian: Uriconian Volcanics. Sheet 152. |
Steep-sided hill rising to 320 m. |
The description takes the form of a traverse up and over the hill. At
the N end of Pontesford Hill is a disused quarry; now a scrap yard. It
is rather insalubrious but rhyolite is exposed. This has some potential
but at the moment is of limited value. A better exposure by the footpath
near the car-park shows brecciated rhyolite; with flow banding and
spherulitic structures dipping at about 40°. The best rhyolite is found
near the top of the hill fort where a NW-facing exposure up to 4 m high
and 10 m across displays fine; flinty rhyolite with good examples of
spherulites. On the steep climb through the plantation small exposures
of rhyolitic tuff can be seen but the path soon goes through
dolerite/basalt. There is evidence of vesicles and texture is fine so
although dolerite is indicated on the geological map; the rock mainly
resembles basalt. Out in the open; at the top of Pontesford Hill; are
sporadic exposures of dolerite while at the summit of Earl's Hill there
are broken fragments of basalt. From the top; extensive panoramic views
allow excellent geological interpretation of the landscape. Purple tuffs
with suggestion of haematite and showing some flow-banding; are exposed
on the steep descent. Following the footpath NE along the bottom of the
hill a loose block of barytes; 0.5 m across; was seen as well as
vesicular rhyolite; the latter indicating explosive episodes of
vulcanicity. The best site on the hill is the impressive scree slope
where fragments of basalt have reached a state of near equilibrium below
the towering crags (SJ 410048). Blocks of scree material are up to 0.5 m
across and presumably owe their origin to freeze-thaw conditions towards
the end of the last Ice Age. It is interesting to note that above the
path the scree looks relatively fresh and has little vegetation whereas
below it has the appearance of a fossil scree; now colonised by mosses
and other ground cover. |
All the exposures mentioned are on or close to public footpaths and are
readily accessible. |
LGS Yes. Designation for the whole hill as it is a significant faulted inlier of Uriconian Volcanics with fair exposures illustrating the
variety of igneous rocks present. The scree slope is surely one of the
few such periglacial features in Shropshire. |
Mineralogy/Petrology |
| 1342 |
SJ 467 066 - extends from SJ 467 066 to 469 066 |
Lyth Hill |
Natural exposure |
Precambrian: Longmyndian: Wentnor Series. |
Exposures on fault scarp of Lyth Hill. |
There are many exposures on Lyth Hill (large and small); this
description only deals with the area between the given grid references.
Here the Wentnor Grit does not seem to be typical and appears to have
been affected by the fault. Because the grits apparently contain grains
of various igneous rocks the colour varies from greenish purple to
blackish. Also the fault appears to have changed the texture to one
where the grains appear fused and resemble an igneous rock. There is a
series of good exposures at the foot of the slope (up to 6 m high) but
there are distinct signs of fragmentation resulting from faulting.
Bedding can be discerned and is steeply dipping towards the east.
Patches of purple and pink occur and there are several quartz veins. The
rock is essentially a coarse grit with a few scattered pebbles. Joints
and fractures give a shattered appearance; there being several small
faults. About 30 m from the west end are slickensided surfaces
associated with quartz mineralisation and brecciation; these are oblique
to the main Lyth Hill fault and have a trend of 120°. As the footpath
climbs round the fence at the west end loose fragments of more typical
purple grit occur and behind the fence small exposures of this are found
in the trees. A quartz vein up to 30 mm thick was seen in the
purple/pink gritty sandstone in which were scattered pebbles up to 3 mm
in size. |
Public footpaths in the country park. |
LGS Yes. Designation because this site while not being the clearest and
easiest to use is important for interpretation of the geology of Lyth
Hill and the effect of faulting in this vicinity. It is recommended that
the whole of Lyth Hill should be a LGS. |
Structure |
| 1343 |
SJ 615 062 to 611 070 |
Chermes Dingle - Leighton |
Stream/brook |
Lower Cambrian: Comley Series; Lower Ordovician: Tremadoc Series:
Sheinton Shales. Sheet SJ 60. |
A
deeply cut stream on the south slopes of the Wrekin. |
Along the Dingle there are many exposures; mainly of Sheinton Shale but
also some exposure of the Lower Comley sandstone and limestone. A strike
fault separates the two formations and although the fault itself cannot
be seen; the approximate position can be inferred by finding the spot
where Sheinton Shales overlie the Comley Limestone. The contact is not
visible but shales are seen dipping north then becoming contorted and
then dipping the opposite way; a few metres upstream; limestone appears
in the stream bed and rather poor exposures are seen in the banks. Hard
bands of dark grey limestone cross the stream bed; weathering along
joints resulting in a broken appearance. Bank exposures are badly
weathered and although greenish sandy siltstones are there; they have
been weathered brownish and are hard to distinguish. There is no regular
bedding; the faces being somewhat chaotic in appearance. The limestone
seen was probably the Lapworthella Limestone; but the Upper Comley
Series; reputedly present here in the Dingle was not seen by the present
surveyor. Downstream of the fault already mentioned; there are small;
discontinuous sections through the Sheinton Shales exposed in the banks.
The three lowest divisions can be examined; Dictyonema flabelliforme
zone; the Transition Beds; and the Clonograptus tenellus zone.
Graptolite specimens were obtained from the two named zones. The
Sheinton Shales are blue/grey or olive in colour; are very finely
laminated; show a high degree of fissility and often weather brown; even
orange. A few large disc-like concretions were seen within the beds;
showing cone-in-cone structure and having a diameter of over 350 mm.
There is much variation in angle of dip; from 80° to less than 20°;
direction of dip is mainly between south and south-east but there are
exceptions where northerly dips are found near the fault with the Comley
Series and in places there are contortions and even 'anticlinal'
structures which give the appearance of folding. |
Not suitable for large groups as the Dingle is private and viewing the
sites requires scrambling along the stream bed and negotiating various
obstacles and steep slopes at times. |
LGS Yes. Designation because Cherme's Dingle provides the most complete
and best exposed section through the L. Sheinton Shales in their type
area (see SSSI reference) including the only exposure of the Transition
Beds in the area. From this locality many species of trilobites and
graptolites were first described. The evolution through time of the
Sheinton Shale fossil fauna can be seen here and this helps in relative
dating of this Formation. |
Fossils and Sedimentology/Stratigraphy |
| 1344 |
SJ 357 137 and SJ 355 136 |
Loton Park - Alberbury |
Quarry (disused) |
Upper Carboniferous/ Permian: Keele Beds/Basal Alberbury Breccia. No
geological map; reference in P. Toghill: 'Geology in Shropshire'. |
West facing slope of NW/SE trending ridge. |
An
extensive linear exposure 60 m across and 4-5 m high; so is an
impressive face. According to R.W. Pocock there is a marked boundary
between the Keele Beds and overlying Alberbury Breccia; but the present
surveyor did not find a convincing one. There is a distinct change near
the top of the exposure from more massive beds to less regular; thinner
strata which at first was thought to be the boundary. However; the lower
beds; which show clear cross stratification; are as full of fragments as
the ones above and do not seem to fit the description of the Keele
sandstones. In particular; there is grading of fragments with some over
80 mm down to a few millimetres - see photo. These beds appear to be
near the base of the Alberbury Breccia rather than belonging to the
Keele Beds. This site would benefit from closer examination. Two metres
to the right of this example of grading is a vertical discontinuity;
probably a fault with infilling and limy precipitation; now occupied by
badgers. Two hundred metres or so SW of the above site at SJ355136; is
an exposure of red-brown medium textured sandstone 3-4 m high. It
contains scattered pebbles rather than fragments; some sub-rounded. The
size of these varies but is up to 40 mm and a crinoid ossicle was
identified. Strata dips at about 20° NNE and the overall appearance is
of irregular; blocky beds with thin horizons in between. Below the main
exposure a more flaggy sandstone is seen. At this site the strata can
more readily be identified with the Keele Beds but the absence of a
geological map makes confirmation impossible. |
Easily accessible from a non-public footpath in the deer park but
permission is necessary. |
LGS Yes. Designation on the grounds of its being near to the
Carboniferous/Permian boundary and complements the other sites at Alberbury giving a full picture of the nature of the distinctive breccia.
Whether this is to be a LGS on its own or combined with others in the
deer park is a matter for discussion. |
Sedimentology/Stratigraphy |
| 1345 |
SJ 583 293 |
Hawkstone
Obelisk |
Cutting (road/railway) |
Triassic: Mercia Mudstone Formation: Tarporley Siltstones. Sheet 138.
New nomenclature from Toghill. |
South scarp slope of sandstone ridge. |
Here there is a distinct boundary between the massively bedded f4 Helsby
Sandstones found in much of Hawkstone Park and the overlying thinly
bedded; mottled Tarporley Siltstones; formerly Waterstones. The boundary
is marked by a recess. The siltstones dip north-north-west at 7° and a
detailed section through the various horizons can be studied from south
to north. Height of the exposure is about 4 m. Above the Helsby
Sandstone is the Esk Bed; loose sand with barytes crystals; according to
Pocock; although the present surveyor was not able to identify it;
mainly through lack of time. However; flaggy; reddish sandstone;
sometimes rubbly and calcareous was clear to see with red siltstone
showing evidence of mica flakes. A hard sandy horizon about 2 m from the
ground was distinctive. Regular parallel jointing; also parallel to the
dip produces a 'bay/promontory' effect here. Besides the red beds are
alternating bands of grey. This description fits Pocock's 6 ft sandstone
layer immediately above the Esk Bed. Given more time; a more detailed
description of the overlying beds could have been done. |
Follow a path east from the Obelisk for about 300 m. The main part of
the cutting is in Hawkstone Park. Avoid the land beyond the 'private'
notice. |
LGS Yes. Designation because here is a clear; significant boundary
between Helsby Sandstone and Tarporley Siltstones and an excellent
section through the latter. |
Sedimentology/Stratigraphy |
| 1346 |
SJ 575 294 |
Hawkstone
Terrace |
Cliff |
Triassic: Sherwood Sandstone Formation: Helsby Sandstone (Grinshill
Sandstone); overlying Wildmoor Sandstone (Upper Mottled Sandstone).
Sheet 138 (older nomenclature f4 over f3). |
Cliffs of the scarp slope of Hawkstone escarpment. |
The footpath along the Terrace runs parallel to impressive cliffs of
pale Grinshill Sandstone; the upper part of which shows excellent
cross-bedding. Traces of copper show up green; and near the Swiss Bridge
discrepancies in dip direction and angle indicate a fault which can be
seen a little further on beside the path. Here the sandstone looks
rubbly and has weathered to produce a pseudo-spheroidal effect. At the
Retreat; soft barytes-rich pale sandstone forms the back face of this
feature; the sand reminiscent of beach sand and the barytes nodules
making an interesting texture. At this point along the terrace are
impressive parallel fault planes with green and orange mineralisation;
trending NNW/SSE. Slickensiding suggests lateral movement; possibly
right to left. A series of faults can be studied between the Retreat and
Indian Rock. Fox's Nob is a pinnacle of Grinshill Sandstone with a flat
slab at the top; consisting of irregular; massive blocks. Barytes forms
discontinuous layers; 20 mm thick standing proud from the surface.
Beautiful cross-bedding occurs here; the dark minerals (iron oxide?)
emphasising the structure. From this point onwards a red sandstone makes
its appearance beneath the pale rock. There is no clear break between
the two but the red sandstone seems to belong to the underlying Wildmoor
Formation; seen at the base of the Red Castle and outcropping over a
larger area in the east of Hawkstone Park. Along Reynard's Walk 10 m of
the latter sandstone is exposed. High angle; large-scale cross-bedding
with barytes following the partings occurs here. About 1.5 m from the
base is a horizontal plane below which the soft; well-sorted; medium
sandstone with no pebbles; is recessed. There are barytes 'flows' up to
a metre long looking like mini frozen waterfalls. The faces described in
this report are but a few and there is much scope in Hawkstone to make
further studies. |
By
footpaths within Hawkstone Park (entrance charge applies). |
LGS Yes. Designation because the sedimentary and tectonic structures
are of excellent quality and the cliff formations are very impressive.
Also; the change from Wildmoor to Grinshill Sandstone can be observed in
several locations. |
Structure and Sedimentology/Stratigraphy |
| 1347 |
SJ 573 298 and SJ 571 295 |
Hawkstone;
Grotto Hill and Red Castle |
Cliff |
Triassic: Sherwood Sandstone Formation: Helsby Sandstone (Ryton and
Grinshill Sandstones) overlying Wildmoor Sandstone (Upper Mottled
Sandstone). Sheet 138 (older nomenclature f4 over f3) |
'residual cliffs' at west end of Hawkstone escarpment. |
At
the top of Grotto Hill; white/buff sandstone (Grinshill) is exposed as
spectacular cliffs. The top 3-4 m consist of irregular cross-bedded
blocks; the inclination being uni-directional towards the SW. Just below
the cross-stratified blocks is a smoothed; concave; copper-stained
surface. Below the copper staining the sandstone bulges out before
over-hanging softer more crumbly material. Height must be about 50 m
with a sheer drop. Underfoot at the view-point on Grotto Hill; fine
'flowing' laminations in the sandstone can be seen and there are
irregular white crystals of barytes which also fills small joints. This
makes an interesting texture. The beds underfoot are seen to dip WNW at
about 20°. Near the entrance to the Grotto itself; formerly a series of
caves and passages associated with copper mining; a fault plane is
evident and the sandstone; fairly fine-grained here; has some iron-rich
horizons. From the view-point; the Red Castle; a small outlier can be
seen clearly; of particular note is the colour change in the rock which
reflects the red Wildmoor Sandstone at its base passing up into the
light Grinshill Formation. Because the remains of the castle are unsafe
it is not permitted for the public to climb up to it at present. Inside
the grotto; old copper mine tunnels have been made into a 'feature' and
green staining and surface encrustation of copper compounds are still
apparent on walls and ceiling. A torch is recommended! One exit leads
down the cliff via 'the cleft' where more thinly bedded sandstone forms
7 m high walls either side of a steep; narrow path which follows a fault
plane. Despite moss; some rough stratification is visible;
cross-bedding; infilled diagonal joints and the whole face has a rubbly
appearance. |
By
public footpaths in Hawkstone Park (entrance charge applies). |
LGS Yes. Designation because this is a spectacular; accessible site
which demonstrates textural and structural features of Grinshill
Sandstone and provides a good view of the transition to red Wildmoor
Sandstone beneath. Link with copper mining is an added feature of
interest. |
Mineralogy/Petrology |
| 1348 |
SJ 2690 2205 and various others mentioned in the text |
Llanymynech and
Blodwell Rocks |
Quarry (disused) |
Lower Carboniferous: Carboniferous Limestone: Lower Limestone. Sheet
137. |
South-east flank of Llanymynech Hill and crest of Blodwel Escarpment. |
Although the best exposures in this area are in Powys and so are not
reported on; the sites described here are good and show impressive
vertical faces in the disused quarry within the Nature Reserve at the
grid reference indicated. The quarry face rises to over 30 m and the
strata look horizontal but this is apparent dip; the true dip being
mostly NE but varies. At the base of the cliff; the beds are thick (0.75
m) with clear stratification; texture is fine and flinty; the rock being
dove grey in colour. There are thin shaly horizons which tend to
disintegrate and sometimes harder; more slaty partings. Near vertical
joints divide the beds into blocks. Apparently there is evidence of
dolomitisation along some of the joints. In these lower beds there is a
saucer-shaped structure thinning out at the edges and about 5 m across;
whether this is a small synclinal structure or a sedimentary one was not
clear. Above 5-6 m the rock looks pink and the beds are more variable in
thickness; some being flaggy. Coarsely crstalline limestone was noticed
but the height of the cliff did not allow close examination of the
higher beds. It is possible to walk from here into Wales and examine the
better known sites at SJ 265 217. 2. From here walk along the Blodwel
Escarpment. The path takes the crest but various small faults cross the
escarpment and are interesting to examine. At SJ 2655 2270; exposures of
limestone with close parallel dip joints are seen; here the dip is about
40° ENE but on the other side of the path; it is 10° SE. This seems to
be the result of faulting; evidenced by a cleft a few metres along the
path; where slickensiding and brecciated rock occur. A central wedge
appears to have dropped and movement is greater on the south side. Trend
of fault is E-W. This seems to be related to the copper mining in this
area. There are other faults cutting across the escarpment; notably one
at SJ 268 233 where the fault leads to two adits at different levels.
Here are big cliff faces with dark-weathering; thick (300 mm to over a
metre); strongly jointed limestone beds with clay-shale partings. The
dip appears to be south-easterly.Views here are magnificent towards the
Welsh mountains. There is plenty of scope to explore this area in more
detail! 3. Just off the footpath at approx. SJ 274 234 there is an
interesting exposure 4-5 m high and extending for 50 m or so comprising
limestone beds of varying thickness (0.10-0.75 m) succeeded by rubbly
limestone which looks like a breccio-conglomerate; roughly stratified
and dipping SE at 10°-20°. It is the latter that is unusual; the
fragments are held in very little chemically precipitated cement and the
rock has a nodular appearance and is poriferous. Large; discoid;
colonial; rugose corals 300 mm across; are found within these beds;
although some are upside down suggesting they have drifted there after
death. The fossils have recrystallised and so much of the detail has
been lost but they are mostly Lonsdaleia floriformis with a few single
corals; probably Dibunophyllum. |
All these sites lie on or near to public footpaths so access is open. |
LGS Yes. Designation for the sites as a whole because they provide a
good range of exposures in the Lower Limestone showing a range of
sedimentary and structural features as well as evidence of the former
copper mining history of the area and are all on the English side of the
border. |
Fossils and Sedimentology/Stratigraphy |
| 1349 |
SJ 432 143 |
Preston
Montford |
Cliff |
Quaternary: Pleistocene. Sheet 152; Drift. |
Severn river cliff |
A
spectacular example of varved clay resting on fluvio-glacial sands and
gravels. The exposure is approx. 3 m high and 5 m across and magnificent
varves are immediately apparent. 1. The lowest metre consists of till
containing unsorted blocks and fragments ranging in diameter from a few
millimetres to over 300 mm. The fragments are angular to sub-angular
with a few more rounded ones. The erratics in the till are variable in
composition; including red sandstone; grey sand/siltstone; tuff;
quartzite; basalt; shale and tiny fragments of amethyst and vein quartz.
In the middle of the till is a convex lens of closely-packed stratified
fragments in a red/brown sandy matrix; apparently dipping towards the
south at 20°-25°. The stratification suggests fluvio-glacial origin for
these deposits. 2. The boundary is definite but uneven with some large
loose blocks marking the change to clays and fine sands. 3. The thin
layers of clay; sand and small fragments are lain on the uneven surface
forming an arched structure on the right. The colours are striking;
being orange; khaki and various shades of brown with a greater thickness
of sand just above the boundary on the left. 4. Above this boundary
zone fragments become isolated and sporadic but the arched structure
continues at the southern end of the exposure becoming more horizontal
upwards and northwards. The varves are excellent examples; varying in
thickness and colour but there seems to be a correlation between the
darker and more clayey horizons. Close up it is possible to distinguish
the alternating fine clays and lighter; slightly coarser; sandier
horizons. 5. At about 2.5 m there is a harder; sandier; coarser; orange
band about 250 mm thick; above which the varved effect seems to fade
out. |
Only through the grounds of Preston Montford Field Centre from whom
permission MUST first be sought. |
LGS Yes. Designation because this is an outstanding and rare example of
clearly exposed varve clays associated with pro-glacial lakes during the
retreat of ice sheets in this area and their interpretation. |
Sedimentology/Stratigraphy |
| 1350 |
SJ 495 073 and see location map |
Condover Pit;
Bomere; Shomere and Betton Pool |
Quarry (disused) |
Quaternary: fluvio-glacial sands and gravels |
Hummocky landscape with depressions and pools. |
The landscape is one of hummocks; depressions (often marshy or
water-filled) and sandy ridges. The sand shows through grass-covered low
hills. Bomere Pool and the others occupy natural depressions in the
glacial drift left by ice-sheets some 15 000 years ago; they are steep
sided and can probably be classed as kettle hole lakes. Groundwater
levels indicate that Bomere Pool and probably the others are perched
features and isolated from groundwater in the underlying sands and
gravels. There is a close correlation between the landscape features and
the contour lines of the 1:25 000 OS map. The Trout Pool (SJ 501 076)
seems to be a kettle hole deepened and restored artificially for fishing
and recreation and there is a seepage channel at its low point flowing
SE intermittently. Above this pool is a small damp depression. At the
Condover Sand Pit; Norton Farm; the site is in a continuous state of
change and as such it is not possible to identify a LGS. There are many
features of geological interest; however; from deep steep-sided kettle
holes; including the place where the Shropshire Mammoth was discovered;
now a clean water lagoon; to unstable banks of pure sand inter-bedded
with gravels. The characteristically hummocky topography is a
reflection of the complex sequence of underlying glacial sands; gravels
and clays which lies below the surface. The thickness of superficial
deposits is dependant upon the surface elevation and variable elevation
of the Keele Beds below the drift and varies from 10 m to over 38.5 m. |
A
lane and public footpath crosses the hummocky terrain and goes along the
north side of Bomere Pool and Betton Pool. Bomere Wood and Shomere Pool
are on private land. Access to the sand and gravel workings need prior
permission from Hansons. |
LGS Yes. Designation because this is a classic landscape of glacial
deposition with kettle hole lakes next to a working quarry where more
detailed sections of sands and gravels can; with permission; be clearly
seen. It is also the place of discovery of the Shropshire Mammoth. |
Geomorphology/Landscape |
| 1355 |
SO 200 814 |
Rhyd-y-Groes |
Quarry (disused) |
Silurian; Clun Forest Formation (ref 1) |
The quarry is excavated in a low ridge which defines the outcrop of an
east to west trending band of sandstone |
In
following the outcrop of a band of sandstone the quarry is orientated
east to west with all the remaining faces on the northern side. The
quarry is overall some 50 m long and is excavated at three levels. The
highest level is at the western end where sandstones are exposed in a 2
m high face. Below this (to the east) is the main intermediate level
where there is a wide face some 5 m high. This displays some three 1 m
thick posts of massive grey/green arkose separated by 100 mm layers of
soft reddish claystone (marl) partings. All units (sandstone and marl)
are cross-bedded with a uniform apparent inclination of about 20° to the
east. Finally there is a lower level at the eastern end where sandstone
is exposed to a height of 8 m. This probably represents the full
thickness of the sandstone band since dip (as measured by inclination of
marl layers) is near horizontal. Unfortunately this lowest level
contains too much rubbish and organic refuse to be approachable. |
From the cross-roads at Bettws-y-Crwyn take the lane heading west. In
600 m a gate gives access to a field at the top of which is seen
‘gruffy’ ground forming a low ridge. The quarry lies immediately on the
far side of this ridge and may be best approached at the left hand (W)
end. |
LGS Yes. Good sizeable exposures of sandstones in the Clun Forest
Formation are rare. Pending any better exposure this locality is
justified for LGS status for its clear presentation of the nature of
those sandstones. |
Sedimentology/Stratigraphy |
| 1356 |
SO 212 784 |
Coed-yr-Hendre |
Quarry (disused) |
Silurian; Dalamanella lunata beds acc. Earp (1940); equivalent to Cefn
Einion Formation of BGS |
|
This roadside quarry presents a joint plane trending north with a
uniform dip of 15° towards 355 (N). The exposure is clearly separated
into a lower and upper part by a disconformity. In the lower part the
grey siltstones are hard and flaggy with much sedimentary detail (e.g.
pinch & swell) suggesting deposition in an energetic environment perhaps
even within the wave base. There are calcareous bands. Most
significantly the rock surface carries a distinctive sheen (or polish)
only seen once before by this surveyor (n the upper Cefn Einion
Formation at Bury Ditches immediately below the Platyschisma Shales).
This is consistent with Earp (1940) who maps this quarry close to the
same Platyschisma Helicites beds. Further confirmation is found in the
abundance of fossils (wholly as casts and dominated by Salopina lunata
and pentagonal columnals associated with borings of Salopina shells).
Above the plane of disconformity the rock is quite different; seemingly
a brown (decalcified?) fine sandstone up to 2 m thick and most
remarkably compacted by slumps so that there is development of
‘spherical jointing’. However surface textures confirm the latter origin
is as a consequence of slumps. |
From Llanfair Waterdine take the road heading NW along the valley of the
River Teme. After 4 km this turns north and the quarry is to be found
just beyond the end of a small plantation on the RHS |
LGS Yes. LGS designation proposed since this as a possibly unique and
certainly significant exposure. Good sedimentary structures fossils and
slumping phenomena near or at the Ludlow/Pridoli boundary |
Sedimentology/Stratigraphy |
| 1361 |
SO 228 881 |
Black Bank (Maesggwyn) |
Quarry (disused) |
Silurian; Knucklas Castle Formation (ref 1) |
The Kerry Ridgeway offers a steep north facing slope down into the Kerry
valley and a gentler undulating slope to the south. Here a minor stream
has developed a distinct gorge which (although small scale) is
sufficiently eroded to have formed near vertical rock walls both in the
main channel and a subordinate tributary. |
The quarry is situated on a south facing slope above the gorge adjacent
to the disused quarry. Dip direction is also due south (ca 220°); rock
type is a very thin flag and quite suitable for use as roof tiles.
Indeed this seems the purpose of the quarry for it is excavated only to
a depth of about 2 m. Ref. 1 shows the locality so close to the
overlying Cefn Einion beds that it could be considered to lie in a
transition zone between the usual thin shales of the Knucklas Castle
Formation and the more massive siltstones of Cefn Einion Formation. The
approach path also passes two other quarries (referenced) and it is a
notable feature that dip direction swings from SW at these to due south
at the current locality |
From Mainstone take the road heading due west which after 3.5 km arrives
at a cross-roads. A paved forest track marked as a ‘no through road’
heads WNW and in 2 km there is a large lay-by on the left hand side.
Just south of this a usually muddy track heads off south-east passing
the two quarries mentioned above on left and right passing through a
gate to arrive after a distance of about 700 m. The 1:25000 OS map marks
a further quarry at SO 232 881 which could be worth investigating |
LGS Yes. LGS designation because the quarry is likely to have been a
source of stone tiles and the development of the gorge section over such
a short distance well reveals the Quaternary (?glacial) processes that
have been active |
Sedimentology/Stratigraphy |
| 1362 |
SO 231 881 |
Unk Gorge (Maesgwyn) |
Natural exposure |
Silurian; Cefn Einion Formation (ref 1) |
Headwaters of River Usk have cut through the underlying rock succession
forming a gorge with rock walls. Since the present stream is far too
small to have eroded this gorge it is likely that it has a glacial
origin. The area south of the Kerry Ridgeway is rich in glacial
meltwater channels (marked on the map; Ref. 1) although the gorge itself
is not so marked. |
With a catchment area of about 4 sq.km on the highest part of the Kerry
Ridgway (altitude ca. 475 m) the headwaters of the River Unk (which
joins the River Clun in Clun itself) have apparently excavated a gorge
in a remarkably short distance within 200 to 300 m of the present day
stream. The gorge section runs downstream (west to east) from SO 226 881
to SO 232 881 over a distance of 600 m. In shape it has a near vertical
south wall typically presented as embayments up to 4 or 5 m high whereas
the north side comprises an undulating slope inclined at an angle of
about 20° to the south. Adjacent to it on the north side are a number of
quarries (4) and rock exposures (all of which show a consistent dip of
20 to 35° between SSW and SW). At its lowest point a 30 by 5 m area of
rock slabs (at SO 2314 8811) shows thin bedded and slightly bioturbated
beds dipping 35° SSW (220° azimuth) providing a suitable starting point
and an explanation for the asymmetric gorge section. It can be seen that
bedding planes are resistant to vertical excavation and the eroding
stream slides down these planes in a southerly direction. It can far
more easily penetrate and remove rock from vertically exposed bedding
planes which form the south wall of the gorge. A similar situation
exists in the channel of the River Camlad where it traverses Marrington
Dingle along the strike of a dipping rock sequence. Moving upstream
from the above point are good views down into the gorge. A rock-walled
tributary from the north enters the gorge at SO 231 815 beyond which
there is a small quarry and then a second tributary at SO 230 814.
Opposite the ‘tile’ quarry (see SO 228 881) a tributary enters from the
south. All three tributaries enter the gorge aligned north-south which
is the direction of a local major joint system. |
From the lay-by on the forest road at SO 223 880 take the path heading
SE and follow it to a gated compound; pass the ‘tile’ quarry at SO 228
881 then on the right of a fence to arrive at the now visible slabby
area opposite the lowest point of the gorge section. It seems reasonable
to assume the area of the gorge has open access. |
LGS Yes. LGS designation as a geomorphological (Quaternary glacial)
site which also includes some significant (Silurian) stratigraphy |
Geomorphology/Landscape |
| 1364 |
SO 233 820 |
Garn Wood |
Quarry (disused) |
Silurian; Cefn Einion Formation |
|
Quarry lies on north side of B-road (B4368) and its floor forms a small
lay-by. Rock is a clearly bedded siltstone/sandstone sequence variously
flaggy and massive. It is slightly calcareous with occasional patches of
brownstone suggesting fossil coquina. Size of the main face is some 12 m
wide and up to 5 m high. However the principal interest is the dip and
evident folding. From right to left there is a steep 45° dip to the
right (west) punctuated by a 3 m wide sigmoidal fold in which dip is
locally vertical. Ref 1 shows a dip arrow at this locality of only 24°
to the WNW. Further (at the extreme left) the dip is seen to ease
(becoming only 10° W) suggesting that the quarry lies on the easterly
limb of a syncline. Some 150 m west along the B-road is a small cottage
behind which are steep vertical quarried faces showing a persistent dip
45° west and a distinctly turbiditic texture. This could imply that
between quarry and cottage is a now eroded anticline. Irrespective of
such speculation the quarry and cottage exposures are considered
illustrative of the nature and scale of folding within the zone of the
Clun Forest Disturbance |
Quarry affords a lay-by on the north side of the B4368 going west from
the village of Newcastle and is found in the first large area of trees
some 1.6 km (1 mile) west of Newcastle. |
LGS Yes. LGS designation for its demonstration of folding and
inference of a syncline/anticline relation. |
Structure and Sedimentology/Stratigraphy |
| 1365 |
SO 235 801 |
Hill House
(SSW) |
Quarry (disused) |
Silurian; Cefn Einion Formation |
Locality lies on the SE flank of a N-S ridge called Hurgin on the base
map of Ref 1. A complementary exposure (somewhat higher in the sequence)
lies on the NW flank at SO 233 808 |
Quarry presents faces up to 4 m high in a number of sections totalling
some 50 m. Bedding is near horizontal and is variously thin bedded and
massive; siltstones and fine grey sandstones. Some sedimentary detail is
evident. The floor of the quarry undulates but is in the main
grass-covered so there is little talus. Most significant is that this
exposure is mapped (Ref 1) as lying just above the Knucklas Castle
Formation which implies some degree of transitional character. The
finding of a cephalopod cast would seem to confirm lower Cefn Einion
Formation. It is also noted that the site with its tectonically
undisturbed bedding lies just to the SE of the Clun Forest Disturbance
zone; nearest exposures of which are at Garn Wood and possibly on Dowke
Hill. |
Nearest sizeable village is Newcastle from where one would take lanes
heading south to Llanfair Waterdine. Hill House is 500 m south of
cross-roads at Stoney Pound; the quarry site is a further 400 m on a
bend trending SW. A short path on the north side of the road at this
point leads immediately to the quarry |
LGS Yes. LGS designation for its demonstration of stratigraphy and
tectonic disturbance |
Structure and Sedimentology/Stratigraphy |
| 1366 |
SO 240 778 |
Bwlch to Cwm-cold |
Quarry (disused) |
Silurian; ?Bailey Hill Formation |
|
This locality comprises a 300 m long E-W section in which observations
of dip reveal strong folding into a synclinal and anticlinal form. This
description starts at the most eastern of the cottages at Cwm-cold (SO
243 778) where a quarry is visible to the north beyond some
outbuildings. Apparent dip is some 50° west; real dip is probably to NW
at a value exceeding 50°. Proceeding west along the access lane to these
cottages: (a) after 70 m two exposures on the left (one near the lane
the other a higher quarry) where dip is now 30° but to the east; (b)
after a further 40 m a second quarry shows apparent dip 45 to 55° also
to the east; (c) at the top of the lane (ca. 250 m from the cottages)
and behind old buildings on the right is exposed highly distorted strata
associated with a fault; (d) just beyond is a small knoll showing
horizontally bedded rock; (e) finally (at Bwlch) as the lane begins to
descend there is a quarried area on the right in which general dip is
now 10° NW although there are sigmoidal distortions containing segments
of higher dip. Rock here is finely bedded blocky siltstone with some
lamination. Excellent kink bands are developed in these thinly laminated
mudstones. The occurrence here of such folding is consistent with the
main expression of the Clun Forest Disturbance described by Woodcock
(1984) for this local area to the north-west of Knighton. |
Bwlch lies about 1 mile north of Llanfair Waterdine on the road heading
north to Newcastle. The lane to the cottages at Cwm-cold branches off to
the right or can be reached via a footpath through trees on the right
hand side |
LGS Yes. LGS designation for its demonstration of tectonic disturbance
(syncline/anticline) in relation to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1367 |
SO 252 842 |
Rhespass |
Temporary excavation |
Silurian; Bailey Hill Formation (Ref.1) |
A
confined valley with stream giving a view NW; very suggestive of a long
approach to a col or pass |
This locality comprises a 300 m long E-W section in which the
excavation on the north side of a bridleway just short of some farm
buildings is a fantastic section through what can only be described as a
‘crumple zone’. The exposure comprises a single 8 m high face extending
without interruption for 50 m. At the right hand end is a sequence of
strong folds (anticline and syncline) with near vertical limbs and sharp
fold hinges on a 3 to 5 m scale. This pattern of distortion continues
all the way to the left with the central part partly hidden by
vegetation. At the extreme left hand end is a structure strongly
suggestive of a thrust where a low angled plane of disturbance appears
to ride over and drag the top of a relatively undisturbed low buttress.
That the excavation presents the response to extreme compression is the
obvious explanation. The locality lies some 1 km NW of the vertical dips
of Graig Hill but nevertheless would seem to lie within the zone of the
Clun Forest Disturbance. |
From Bridge Farm at SO 259 840 an initially straight bridleway leads
just north of west to reach the excavation after 650 m. This bridleway
continues along the valley outlined under Geomorphology |
LGS Yes. LGS designation for its demonstration of tectonic disturbance
in relation to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1369 |
SO 255 872 |
Churchtown Hill
Mainstone |
Quarry (disused) |
Silurian; Bailey Hill Formation |
Steep hillside with outstanding ridge exposing rock and adjacent hollow |
This locality embraces a quarry section and at least 3 large natural
exposures. Of most interest are tectonic features with large dip angles
and strong faulting possibly demonstrating fault drag. A detailed ground
survey was carried out on a second visit - copy attached. This confirmed
that locally there is a consistent dip direction to the SW with value of
45-55°. Such values are common in nearby exposures (e.g. quarries in
Mainstone) and are assumed to be due to large scale folds within the
zone of the Mainstone fault and/or the Clun Forest Disturbance. The
natural exposures and the quarry show mainly planar laminated dark grey
siltstones and fine sandstones typical of Bailey Hill Formation. Within
the quarry the apparent dip in the east-west aligned face changes
swiftly from 45° to 80° near the fault which is exposed at the western
end of the face. There are major bedding contortions within this fault
(see sketch) which are here interpreted as due to fault drag effects on
the assumption that the fault downthrows on its western side |
From Mainstone take road heading due west. A quarry with lay-by occurs
in a re-entrant after 2 km |
LGS Yes. LGS designation for its demonstration of fault drag; but
expert second opinion is sought to compare with other possibly similar
exposures in the vicinty |
Structure and Sedimentology/Stratigraphy |
| 1374 |
SJ 653 418 |
Coxbank |
Quarry (disused) |
Jurassic; Lower Lias |
A
small stream is running over bedrock which lies some 15 m below till
cover within which there has been a small quarry trial. |
Exposure show 3 m height of grey to dark grey blocky and shaly silty
claystone. A large clam was found and there is clear scope for more
fossils. Many stream-bed and stream-bank repetitions found in River
Duckow for 3 km southwards. Note added by MA: The BGS Nantwich Memoir
(Poole E.G. & Whiteman (1966)) records several exposures of soft
blue-grey mudstone containing a sufficiency of fossils to confirm a
detailed zonation of the Lower Lias. Grid References of these exposures
indicate localities close to this one. |
Near road and tracks; below farm on hill plateau above. |
LGS Yes. Designation because this is the only known Lias exposure
within the Shropshire-Cheshire basin. |
Sedimentology/Stratigraphy |
| 1375 |
SJ 626 167 |
Longswood Farm
- Crudgington |
Quarry (disused) |
The Hillock is Triassic; Sherwood Sandstone Group; Kidderminster
Formation (pebble beds); The surrounding ‘plain’ is Permian; Bridgnorth
(Lower Mottled) Sandstone ref. 1 (Solid Edition); This unconformity is
regionally taken as the Permian/Triassic boundary |
The hillock of height 25 m above the surrounding plain would seem to
represent a relic of Kidderminster Formation Pebble Beds overlying an
alluvium covered plain of Bridgnorth Dune Sandstone. |
The quarry face is 80 m long east to west and up to 10 m high. Dip is
7° west. It looks over a small bend in the course of the River Tern the
opposite bank of which is vegetated. Exposed rock is a ‘big river’
cross-bedded sandstone; only locally pebbly in lower half. There are
some darker siltier lenses and greenish bed parallel streaks (these
could be interfingered aeolian dune sandstone from underlying beds).
There is a splendid set of about 10 swell faulted joints dipping 65° to
east giving an antipathetic joint set (see sketch). |
The site is adjacent to a public footpath which runs between the Weald
Moors on the A442 and Longdon on Tern on the B5063. Both roads run
north from Shawbirch. Note that the site is used for motor-cycle
scrambling. |
LGS Yes. Designation because shows both tectonic & sedimentary
features. |
Structure and Sedimentology/Stratigraphy |
| 1376 |
SJ 365 087 |
Quarry Woods |
Quarry (disused) |
Carboniferous; Upper Coal Measures; Westphalian C; Coed yr Allt Beds (by
extrapolation from Shrewsbury Sheet; ref 1) |
Sandstones form a wooded ridge orientated NW to SE |
The quarry presents an 8 m high section extending along 60 m long
faces. This is divided by an apparent erosion surface. The lower half
is of massive mega-rippled sandstone showing conspicuous ‘onion skin’
weathering. The upper half is cross-bedded and conglomerate channelled
sandstone and includes coal flecks and pyrite clasts. |
The woods lie on the NE side of the B4387 road from Minsterly to
Westbury some 1 km short of the latter place. Possible to walk in from
the road. |
LGS Yes. Designation because this is an exemplary exposure of Coed yr
Allt Beds |
Sedimentology/Stratigraphy |
| 1377 |
SO 802 951 |
Upper Ludstone |
Cutting (road/railway) |
Triassic; Keuper Series; Lower Keuper sandstone (ref. 1); Sherwood
Sandstone |
Road Cut in new by-pass on B4176 road to Dudley ascends a west facing
scarp in which rocks dip moderately (10 degrees) to east. |
On
north side of cut exposure is long and clean and access is safe but
somewhat noisy from passing traffic. Because of the easterly dip the
strata forms terraces up the bank and a total thickness of about 25
metres is exposed. It comprises all grades from siltstone up to pebbly
sandstones (generally strong) of a purple colour and clearly indicative
of deposition in a range of energetic environments. There are small
faults lithic calcareous intraclasts and exotic pebbles with varied
diagenetic colours and cements. |
There is parking in a gateway at the foot of the bank on the north side;
it is only a short distance to a large and prominent road house. |
LGS Yes. Designation because this is as an exemplary exposure in the
Sherwood Sandstone |
Sedimentology/Stratigraphy |
| 1378 |
SJ 551 138 |
The Criftin |
Quarry (disused) |
Precambrian; Longmyndian; Stretton Group undivided of Haughmond Hill |
Lies on shoulder or flank of the horst-like feature of Haughmond Hill |
Exposures show steeply folded slaty (cleaved) wackes in 5 mm graded
couplets of graded claystone on fine sandstone. These are generally
‘right way up’. Presumed bentonite layers are common. There is one
reverse-graded volcaniclastic bed. Similar exposures occur around the
Criftin 100 m to the south. |
From Upton Magna take road heading north towards Haughmond Hill. There
is easy access to the quarry on the left hand side after 1 km. However
the quarry is private with some connection to the Criftin passed en
route. Here the owner is friendly and knowledgeable so to also seek
access permission here beforehand is advised. |
LGS Yes. Designation because this is a very relevant exposure of the
Precambrian Stretton Group |
Sedimentology/Stratigraphy |
| 1379 |
SJ 596 275 |
Hopley Farm |
Quarry (disused) |
Triassic; Scythian; Sherwood Sandstone Group; Wilmslow Sandstone
Formation (ref. 1) |
Quarry excavated in slope of hill-plateau capped by Grinshill Sandstone |
A
9 m face is still preserved in this large old quarry and almost all the
strata are accessible. This is mostly a red silty thin bed or a thicker
bedded claystone with also some pale greenish siltstone visible. No
pebbles are to be seen. Possible minor faults to the east emphasise the
jointing - a north to south fault lies immediately adjacent according to
ref. 1. The quarry is said to have been used as a source for brick
making. |
On
the A53 2 km SW of Hodnet a track leads NW past Hopton Farm into the
Hodnet Estate and leads into open woodland towards Hopley Farm |
LGS Yes. Designation because the Wilmslow Sandstone Formation is a
rarely exposed unit |
Sedimentology/Stratigraphy |
| 1380 |
SJ 644 211 |
Great Bolas (W) |
Natural exposure |
Triassic: Bunter Series; Lower Mottled Sandstone (ref. 1); Kidderminster
(or Chester) Pebble Beds lying on Bridgnorth (Dune) Sandstones (alt.Helsby
Sst.) |
in
valley edge; an extremely convoluted erosive contact.in quarried bluff
edge of River Tern alluvium |
Exposure is 300 m long scar up to 5 m high (strike section near
horizontal) showing pebbly sandstones with conglomerate channel basal
scours on dune-bedded sandstones. |
Bank of River Tern has public footpath which can be reached by path from
Cold Hatton to west on A442 or to east from bridge over River Meece
south of Great Bolas. |
LGS Yes. Designation because shows channel basal scours. |
Sedimentology/Stratigraphy |
| 1381 |
SO 234 931 |
West Penyllan |
Quarry (disused) |
Silurian; Wenlock Series; Nantglyn Mudstones Formation; Gyfenni Wood
Shales Member (ref 1) |
Quarry excavated in south facing hillside which is perhaps steepened by
a palaeovalley cut. |
Quarry exposes some 8 metres of thin bedded shaly siltstones with some
100 mm thick shale partings. Dip is 5° SW according to ref 1. There
are a few calcareous septarian nodules. The Gyfenni Wood Shales are
described as hemipelagite (a dark grey silty laminate) (Cave Hains &
White in ref. 2 page 87) forming a background deposit during Wenlock and
early Ludlow times; fossils are pelagic notably graptolites & orthocones.
Monograptids are plentiful at this locality. |
Quarry lies on the north side of the A489 Churchstoke to Kerry road some
4 km from Churchstoke. |
LGS Yes. Designation because this is as a good example of the Silurian Gyfenni Member and the only Shropshire locality for this unit |
Sedimentology/Stratigraphy |
| 1382 |
SJ 391 023 |
Lower Vesson |
Track/roadside |
Ordovician; Tremadoc Series; Habberley Shale Formation (refs. 1 & 2);
note that no intrusions are marked on ref. 1 at this locality |
|
Exposures (extending for about 30 m) show steeply cleaved micaceous
silty claystones; a dark diorite showing pyrite is intruded; this
weathers to a brown sandstone like texture. The shale at the contact is
altered to a pale hornfels and is spotted to resemble a pellet
grainstone. More hornfels variety could be revealed by clearing and
excavating. A quartz vein is also present. Overall the outcrop probably
extends for about 100 m along the track which is part of a mountain bike
circuit. |
From Snailbeach Mine a road leads east up the valley to Upper Vessons
farm & church from whence good public tracks and Forestry biking trails
continue eastwards to Lower Vessons. The site is approx. 300 m NNW of
Lower Vessons. |
LGS Yes. Designation proposed as a site showing thermal metamorphism of
fine grained sediments |
Mineralogy/Petrology |
| 1383 |
SJ 520 124 |
River Severn (Monkmoor) |
Stream/brook |
Carboniferous; Upper Coal Measures (Westphalian C); Ruabon Marl (ref.
1) |
Natural crags and river bed shoals best seen at low water |
About a 20 m length of section is exposed where the river runs north to
south. This lies on the outside of a river bend and lies mainly in the
river bed extending about one half river width. It is therefore best
examined at times of low water levels. Upstream is a modest dip to the
north. At south end of section are some 7 m of clays; variously purple
to blotchy green. Scarce pieces of conglomerate; intraclasts; calcareous
or dolomitic; and ‘stirred’ sandy lenses are occasionally exposed by
landslips off the bank. The middle 10 m show fine sandstones with
ripples and erosive bases and sub-equal redder siltstones. The top 3 m
comprise siltstone sandstone and breccia lenses. There may be sandstones
under the bridge piers. |
From the suburb of Monkmoor there are various ways to reach the west
bank of the River Severn and walk downstream along public footpath to
the railway bridge. The river bed rocks are below the Railway Bridge.
This locality should not require any particular permissions to visit. |
LGS Yes. Designation proposed as a rare example of a locality showing
detailed lithology of the Ruabon Marl |
Sedimentology/Stratigraphy |
| 1384 |
SO 538 734 |
Poughnhill
(Tinker’s Hill/Caynham Camp) |
Quarry (disused) |
Silurian; Ludlow Series; Whitcliffe Formation (Ref. 1) |
Pronounced ridge due to faults bringing harder rock to the surface |
Near Bradnor Hill (Kington) the Leinthall Earles Fault branches east
from the Church Stretton Fault System and runs east of north-east to
Titterstone Clee and beyond. Its downthrow to the north-west is
consistent with the throw of the Church Stretton fault but at Overton a
second branch is formed which downthrows to the south-east (BGS 2000).
As a result a horst-like feature is developed in the sense of Park
(1997; fig. 2.8). This throws up a long narrow outcrop of Ludlovian and
early Pridoli rocks through the cover of Raglan Mudstone so forming a 4
km ridge south-west to north-east from Tinker’s Hill to Caynham Camp.
Beyond Caynham the outcrop is abruptly terminated by a cross fault
downthrowing to the north-east. The Ledwyche Brook cuts through this
ridge and appears to be a misfit stream within the current valley and
probably hosted the River Corve prior to capture by the Teme in the late
stages of the Devensian. The quarry at this site (opened on the western
side of the gap) was for building stone. It exploited the outcrop of
Whitcliffe Formation and was of considerable size; the main face is some
200 m long. All of this is now degraded and vegetated save for one
pillar like section 6 m high and 8 m wide which reveals clean rock. This
section offers an alternating sequence of smooth faced decalcified
siltstone up to 100 mm thick and rough surfaced finer grained siltstones
up to 300 mm thick; there are occasional partings less than 10 mm thick.
There is much sedimentary detail including laminations and minor erosion
surfaces. The sequence resembles the Upper Whitcliffe Beds in the dingle
above the Whitcliffe type section (SO 509 741). Fossils are assessed as
being common; one obvious bedding plane showed
Salopina lunata and
Protochonetes ludloviensis
inside the smooth faced facies. The walk (east) up to Caynham Camp is
instructive for the views and appreciation of the context of the Ridge
in relation to the anticline beneath Mortimer Forest. |
Exit Ludlow via the Sheet Road; continue straight over the A49 bypass
and through the village of Sheet. The road next enters a short defile
where parking is most convenient (opposite a waterfall over a weir in
the Ledwyche Brook on the left-hand side). On the opposite side a
footpath sign indicates a direction over the ivy-covered quarry floor
towards the quarry section. The quarried area is crossed by a public
footpath which gives adequate access. The walk (east) up to Caynham Camp
is instructive for the views and appreciation of the context of the
Ridge in relation to the anticline beneath Mortimer Forest. |
LGS Yes. Designation proposed primarily for its illustration of the
geomorphology of a ridge developed as a consequence of a splay fault
(part of the Church Stretton fault system). The Ledwyche Brook appears
to be a misfit stream within the current valley and probably hosted the
River Corve prior to its capture by the Teme in the late stages of the
Devensian. The similarity of the visible exposure to the Whitcliffe at
Ludlow is also of interest. |
Geomorphology/Landscape |
| 1396 |
SO 468 955 |
Hough's Coppice |
Track/roadside |
Silurian; Wenlock Limestone Formation; Tickwood Beds (as a member)
(Ref. 1) |
Hillside below westerly flank of Caer Caradoc and showing slope angle
determined by underlying lithology |
From the A49 lay-by the public footpath ascends an open grassland field
underlain by Wenlock Shales. The map of Ref. 1 is in error here since
it shows Lower Ludlow Shales. Above is a steeper slope carrying a heavy
tree cover and known as Hough’s Coppice. As the footpath enters this
woodland a drainage ditch contains examples of well rounded cobbles of
fluvioglacial material which occurs on the sides of the Church Stretton
Valley at this elevation. The footpath climbs through the coppice at a
slant; in a vertical direction the woodland is 55 m wide but the
footpath takes 135 m to reach the gate at the uppermost edge. From the
lower entrance at the change of slope there is a rock exposure on the
right-hand side but it is 40 m to the first clear exposure. Here a
section one m high shows a compact sequence of poorly bedded grey
calcareous shales up to 100 mm thick with harder irregular flaggy muddy
grey limestone bands from 50 to 80 mm thick. This lithology is
characteristic of Tickwood Beds (which occur as a horizon immediately
below the Wenlock Limestone itself). Dip here was measured as 30
degrees to a 120 azimuth (SE). The strike direction cuts across the
flanks of the hillside only a little steeper than the line of the
footpath. As a result only a relatively thin section of beds is thereby
exposed. In a further 20 m a second exposure shows the harder beds much
thicker (up to 60 mm) and of a more massive nature. Thin shales are
exposed under the roots of an adjacent tree. It is a further 70 m to
the upper gate and the limestone is now slightly more nodular but very
short of the usual nodular character found in the Wenlock Limestone
proper. Beyond the gate are again open fields with slope angles
reverting to those of the lower field but underlain by Lower Ludlow
Shales (Eltonian). A stream defines the left-hand side of these fields
but has provided no useful exposure; it is dominated by Uriconian
rhyolites etc. derived from Caer Caradoc. The BGS sheet (Ref 1) shows
an outcrop width of 200 m and places the upper boundary of the Wenlock
Limestone outcrop well up these fields where it is succeeded again by
Wenlock Shales. There is nothing to suggest the presence of the actual
Wenlock Limestone here. |
2
km north of the traffic lights on the A49 at Church Stretton is a lay-by
on the right-hand (east) side. From here a signed footpath crosses the
field towards woodland with Caer Caradoc clearly visible above. |
LGS Yes. Designation proposed as the largest and most accessible
outcrop of Wenlock Limestone “shelf” facies in close proximity to and
immediately west of the F1 component of the Church Stretton Fault |
Structure and Sedimentology/Stratigraphy |
| 1397 |
SO 354 952 |
Ridge (SW) |
Quarry (active) |
Precambrian; Wentnor Group; Bayston-Oakswood Formation (Ref. 1) |
Shallow re-entrant on western flank of elevated Precambrian landscape of
Norbury and Linley hills. Overlooks to the NW the deep valley of the
Pontesford-Linley fault separating the Precambrian from the Ordovician
Stiperstones. |
This new quarry in the purple sandstones of the Bayston-Oakswood
Formation would appear to offer the best evidence for strata inversion
(see survey report for Nurton SO 353 936). The quarry section is
semicircular in section with a diameter of some 15 m. It lies on the
crest of a low ridge and the height of the face varies from about 4 m in
the centre to zero at the extremities. Dips are constant and consistent
at around 20 degrees to the west. The quarry presents some 5 to 6 beds
of massive flat jointed purple sandstone up to one metre thick. These
are separated by beds of dark purple friable material which varies from
sandstone with same grain size as the massive beds through finer
sandstone to distinct mudstone (at the right hand end). Such a
lithology offers a number of indicators for inversion. Specifically
these include: (1) a detectable grading in the thinner sandstones but a
grading in both senses (up and down); (2) possible incipient load casts
on the upper surface of the massive sandstones but unconvincing since
this may be associated with the jointing - the “casts” form as shallow
convex surfaces on the top surface between the orthogonal joint planes;
(3) pick-up clasts of purple mudstone are seen near the base of some
sandstones but equally such clasts can occur near the top; (4)
cross-bedding would seem likely in these coarse grain sediments but no
evidence was found by the surveyor. |
Easiest approach is from the hamlet of Cold Harbour (signposted from the
B4383 1.5 km south of Bridges). Take the minor road south towards
Linley and the quarry will be seen on the hillside above the first
cattle grid (where parking can be had); distance about 2 km.
Alternatively take this same minor road north from Linley where it is
signposted to Cold Harbour. The cattle grid is the second one (distance
about 3 km). |
LGS Yes. Designation proposed as a somewhat unusual
sandstone/siltstone/mudstone sequence and the best candidate for
demonstrating inversion of the B-O Formation. |
Sedimentology/Stratigraphy |
| 1398 |
SO 331 971 |
Mucklewick Hill
Summit |
Natural exposure |
Ordovician; Llandeilo; Hope Shale Formation; Hyssington Volcanic Member
(Ref. 1) |
Highest point among ridges of hard volcanic rocks |
The local rocks are those of the Hyssington Volcanics which are
interbedded within the Hope Shales and have a strong sedimentary
character. This can be seen on the east flank of the hill where a
steeply dipping bedding surface is exposed comprising grey
volcaniclastics that also comprise the abundant talus that surrounds the
summit (372 m AOD). However these are better examined elsewhere and it
is the view that is the principal feature and can be summarized in three
parts: (1) The most immediate feature is the ridge from Grit Hill to the
NE some 3 km to the SW. Like other examples within the Shelve Inlier
such hard rock ridges often show the offsets caused by transverse (SE to
NE) normal faults. (2) At the next level is the local topography which
is dominated by the two zones of lower ground of Hope Shales. To the SE
is the axis of the Llan Syncline between here and the tree covered high
ground of Brooks Hill (itself essentially the same Hyssington Volcanics
as Mucklewick). To the west is the complementary Shelve Anticline with
an axis between here and the dominant Corndon Hill. To the right (NW)
can be seen the ridge of Stapeley Hill (itself a second volcanic
sequence with the Hope Shales higher up the sequence than the Hyssington
Volcanics and of a much more basic character). (3) Finally on a wider
360 degree panorama is the consequence of hard and soft rock sequence
within the regional geology. To the NNE is the high point of Myton
Dingle and the quartzite tors of the Stiperstones ridge extending south
to a termination on Black Rhadley Hill. Again to the south and going
behind Corndon Hill are 5 hills in a line shaped in terms of scarp and
dip by their underlying sediments and volcanics. North of Corndon is
the Stapeley Ridge continuing round to high ground occupied by the
Silurian of Venus Bank and then finally the distinct marker of the tree
cluster of Bromlow Callow. |
Mucklewick Hill can be approached by numerous walking routes using the
network of local paths. These intersect the road network at places such
as: Shelve; The Bog; Nind; and the Grit mines on the A488. |
LGS Yes. Designation proposed a splendid panorama of the local
geological structure and stratigraphy |
Structure and Sedimentology/Stratigraphy |
| 1399 |
SO 328 966 |
Mucklewick Hill
(SW) |
Quarry (active) |
Ordovician; Llandeilo; Hope Shale Formation; Hyssington Volcanic Member
(Ref. 1) |
Quarry is situated on the SE facing flank of a NE trending ridge of
volcanic rocks |
To
quote from the BGS Memoir for the Montgomery Sheet “the Hyssington
Volcanics are made up of principally acid vitroclastic crystal and
lithic tuffs laminated tuffites and associated volcaniclastic
sedimentary rocks interbedded with the mudstones of the Hope Shales”
(Ref. 2 page 19). The single main face of the quarry is some 40 m long
and up to 6 m high and presents bedding planes which dip 45 degrees to
the SE. These planes are mainly of the Hope Shales of dark grey
mudstone variously blocky or fissile. The shales are interbedded with a
variety of volcanics the extraction of which is the purpose of the
quarry. At either end of the main face are dip sections which show the
interbedding in terms of the thickness of the individual units. There
is a marked difference between these two sections which suggests that
the quarry face is not exactly cut along the strike. The quarry
contains abundant talus examination of which quickly confirms the wide
range of rock types represented in the Hyssington Volcanics. The Hope
Shales show some variations. Some examples show a hardening of the
original mudstone giving a more fissile character that suggests some
localized heating. There are also some good examples of the concentric
diffusion patterns (Leisegang rings (?)) implying processes whereby
components of the volcanics have interpenetrated the shales. There is a
host of different volcanic rock types ranging in terms of particle size
from finely laminated to heterogeneous grits with differences of
hardness colour and so on. The dip section at the right hand end of the
quarry (NE) is roughly 8 m wide and shows within that distance at least
8 bands of shale (none thicker than 200 mm). The interbedded volcanics
vary in thickness by a factor of 100 (from 50 mm to 5 m). Contacts with
underlying shales are sharp with slight load casting and shale
distortion evident. This section provides an excellent opportunity for
a very detailed examination; stratigraphic logging would be
appropriate. The section at the left hand end is in sharp contrast.
Some 10 m wide it is of massive grey crystallinity with some fining
upwards but impressing mainly with the perfectly flat orthogonal joint
faces. Its sedimentary nature is deduced from the base which rests on
the bedding plane of underlying shales with an additional thin (<10 mm)
shale horizon some 100 mm above the base. The crest of the ridge above
the quarry shows numerous natural outcrops aligned in a NE direction but
then is abruptly terminated. From the BGS map of Ref. 1 it appears that
a transverse fault down-throwing to the north has offset the outcrop to
the left (NW) where it continues as a less conspicuous feature. A
strong ridge now appears to the right (SW) representing a different
“unit” within the Hyssington Volcanics. |
The area of Mucklewick Hill is well endowed with footpaths. By vehicle
from the A488 take the turn east signposted to Nind. After 1 km turn
left at the T-junction signed as a no through road. A lay-by will be
encountered on the right-hand side opposite the second of two sets of
farm buildings. Continue by walking further along the lane and take the
first track branching to the left. This leads directly to the quarry
which shortly becomes visible. Note the numerous examples of volcanics
which occur in the track surface. Alternatives are directly by footpath
from the point at SO 324 961 on the A488 distance 0.5 km or by footpaths
from Shelve via Grit Hill and Shelve Pool; distance about 2 km. |
LGS Yes. Designation proposed as a splendid demonstration of the Hyssington Volcanics - acid vitroclastic crystal and lithic tuffs;
laminated tuffites and associated volcaniclastic sedimentary rocks
interbedded with the mudstones of the Hope Shales |
Sedimentology/Stratigraphy |
| 1400 |
SO 449 943 |
Cardingmill
Valley (Church Stretton) |
Quarry (disused) |
Precambrian; Longmyndian; Burway Formation |
Situated near exit from Cardingmill Valley; one of a number of steep
sided non-glaciated “batches” which drain the SE flank of the Longmynd |
It
was Susan Beale (previously Secretary of the SGS) who first observed a
number of thin orange seams lying along the bedding planes of this
quarry. She considered them to be the result of contemporaneous ash
falls but (whilst they may be of volcanic origin) an ash fall has not
been confirmed by subsequent observations. The quarry on the NE side of
the valley was excavated in the turbidite sequence of the Burway
Formation – previously known as the Burway Flags. It presents a face of
about 5 m height aligned roughly in the dip plane and at right angles to
the strike. Younging direction is from right to left. Some six orange
seams are clearly visible each one lying upon the planar shale component
of the turbidite units and overlain by the similar planar basal fine
sandstone or siltstone unit. The seams were therefore deposited in the
intervals between turbidite flows. The seams are typically of thickness
between 10 and 30 mm. Spacing between the seams is irregular. From
right to left in the younging direction: Thickness/Spacing: 20-30 mm /
1.16 m; 15 mm / 0.28 m; 10 mm / 4.17 m; 10 mm / 0.52 m; 2 of ca. 10 mm /
0.61 m; 10 mm / 1.22 m; ca. 10 mm. The discovery of around 5 similar
seams in the Batch Valley at approximately the same horizon (some 100 m
above the base of the Burway Formation turbidites) prompted a search to
establish their lateral extent. Going south they have been found also
in similar numbers: in Cwmdale on Novers Hill; in Townbrook Hollow as
two seams; and in Ashes Hollow as one seam. They have not been found
north or south of these two limits. Separation distances between the
individual bands differ so much at each of the above places as to
prevent any correlation. What all the seams have in common are
sedimentological effects. The seams have a lamination which resembles
that in certain mudstones such as that of the Stretton Shales. A thin
section indicates a clay mineral composition with some amounts of
secondary quartz mineralisation. Bases of the seams can be perfectly
flat but more usually show undulations which vary from fine to
unequivocal load casts simply indicating the degree of diagenetic
hardening of the underlying turbidite shale when the seam was emplaced.
Traced upwards the seams show a gradational texture involving an often
present purple band 1 to 2 mm thick succeeded by fine laminations
showing that the full thickness of the seam is greater than that of the
orange colouration In at least two cases it has been noticed that this
full seam can suffer slumping producing short wavelength folds of up to
10 mm amplitude. |
Cardingmill Valley is signposted from Church Stretton and the quarry is
on the right-hand side 50 m past the first cattle grid |
LGS Yes. Designation proposed as the type section of ?volcanic seams
deposited in the intervals between turbidite flows |
Sedimentology/Stratigraphy |
| 1401 |
SO 257 888 |
Dolfawr (Lower
& Middle) |
Quarry (disused) |
Silurian; Ludlow Series; Bailey Hill Formation (Ref. 1) |
Exposures lie mainly on valley sides of the River Unk immediately
downstream of a river capture which changes its course from SE to NW and
from along strike to across strike. |
The identifying grid reference SOI251887 is placed adjacent to Lower
Dolfawr Farm. Exposures are alongside public footpaths and show some
degree of disturbance as folding and thrusting which are presumed to
arise from compressive forces (stress) associated with the Clun Forest
Disturbance – see Woodcock (1984). It is the view of the surveyor that
the exposures (1401-1407) are illustrative of this effect and all link
together as a single unit – albeit of appreciable scale; the most
separated exposures are 1.25 km apart. As such they warrant some
particular examination going well beyond what can be presented in this
report; here the concern is only with the location and outline
description of each exposure. SO 257 888 extends westwards from a
gateway down the slope of a track. At the start is a continuous section
2 m high of undisturbed Bailey Hill Beds showing shallow dip and the
characteristic fine sandstone and siltstone couplets. The
distinguishing graptolite Saetograptus was found here. After 20 m of
exposure these beds suddenly abut against highly disturbed strata of the
same Bailey Hill Formation with near vertical dip at 80 degrees west.
The zone of demarcation appears to be a fault although it has produced
very little in the way of drag effects. The near vertical strata then
continue westwards for 20 m. The main variations are dip angles
sometimes down to 60 degrees and some bending of the strata.
Observation of grading and slight load casting of the sandstone units
suggests the whole width of this outcrop youngs to the west. |
Access to Dolfawr is by public footpaths of which there are various
options. The most dramatic is that following the River Unk from the
near the plantation as point 475 near which there is abundant parking.
Other routes are: south from Pantglas (some parking); NW from Edenhope
(verge parking only); and east from Upper Edenhope. |
LGS Yes. Designation proposed as these are textbook quality exposures
of folding and thrusts belonging to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1402 |
SO 247 887 |
Dolfawr (Lower
& Middle) |
Quarry (disused) |
Silurian; Ludlow Series; Bailey Hill Formation (Ref. 1) |
Exposures lie mainly on valley sides of the River Unk immediately
downstream of a river capture which changes its course from SE to NW and
from along strike to across strike. |
The identifying grid reference SOI251887 is placed adjacent to Lower
Dolfawr Farm. Exposures are alongside public footpaths and show some
degree of disturbance as folding and thrusting which are presumed to
arise from compressive forces (stress) associated with the Clun Forest
Disturbance – see Woodcock (1984). It is the view of the surveyor that
the exposures (1401-1407) are illustrative of this effect and all link
together as a single unit – albeit of appreciable scale; the most
separated exposures are 1.25 km apart. As such they warrant some
particular examination going well beyond what can be presented in this
report; here the concern is only with the location and outline
description of each exposure. SO 247 887 shows a section of length 100 m
which extends from a gate south-eastwards down the track. It is
dominated by near vertical strata with some local curvature suggesting
involvement of folding. The section also includes an old quarry which
(like all the trackside exposures) has come about as a result of the
local farmer(s) excavating the side bank for hardcore. |
Access to Dolfawr is by public footpaths of which there are various
options. The most dramatic is that following the River Unk from the
near the plantation as point 475 near which there is abundant parking.
Other routes are: south from Pantglas (some parking); NW from Edenhope
(verge parking only); and east from Upper Edenhope. |
LGS Yes. Designation proposed as these are textbook quality exposures
of folding and thrusts belonging to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1403 |
SO 250 886 |
Dolfawr (Lower
& Middle) |
Quarry (disused) |
Silurian; Ludlow Series; Bailey Hill Formation (Ref. 1) |
Exposures lie mainly on valley sides of the River Unk immediately
downstream of a river capture which changes its course from SE to NW and
from along strike to across strike. |
The identifying grid reference SOI251887 is placed adjacent to Lower
Dolfawr Farm. Exposures are alongside public footpaths and show some
degree of disturbance as folding and thrusting which are presumed to
arise from compressive forces (stress) associated with the Clun Forest
Disturbance – see Woodcock (1984). It is the view of the surveyor that
the exposures (1401-1407) are illustrative of this effect and all link
together as a single unit – albeit of appreciable scale; the most
separated exposures are 1.25 km apart. As such they warrant some
particular examination going well beyond what can be presented in this
report; here the concern is only with the location and outline
description of each exposure. SO 250 886 is another long exposure which
mixes elements of verticality folding and thrusting in quite a dramatic
manner. The strata retain a recognizable Bailey Hill beds texture of
sandstone/siltstone couplets. |
Access to Dolfawr is by public footpaths of which there are various
options. The most dramatic is that following the River Unk from the
near the plantation as point 475 near which there is abundant parking.
Other routes are: south from Pantglas (some parking); NW from Edenhope
(verge parking only); and east from Upper Edenhope. |
LGS Yes. Designation proposed as these are textbook quality exposures
of folding and thrusts belonging to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1404 |
SO 245 885 |
Dolfawr (Lower
& Middle) |
Quarry (disused) |
Silurian; Ludlow Series; Bailey Hill Formation (Ref. 1) |
Exposures lie mainly on valley sides of the River Unk immediately
downstream of a river capture which changes its course from SE to NW and
from along strike to across strike. |
The identifying grid reference SOI251887 is placed adjacent to Lower
Dolfawr Farm. Exposures are alongside public footpaths and show some
degree of disturbance as folding and thrusting which are presumed to
arise from compressive forces (stress) associated with the Clun Forest
Disturbance – see Woodcock (1984). It is the view of the surveyor that
the exposures (1401-1407) are illustrative of this effect and all link
together as a single unit – albeit of appreciable scale; the most
separated exposures are 1.25 km apart. As such they warrant some
particular examination going well beyond what can be presented in this
report; here the concern is only with the location and outline
description of each exposure. SO 245 885 is the exemplar of the set. It
is an unusual excavation of the two outer sides of a small hillock or
ridge giving two outward faces at 90 degrees to each other and each some
20 to 25 m long and up to 4 m high. The westward face shows a range of
exquisite folds which can be seen to develop from fairly low dip ground
to the left. At the right these folds merge into unequivocal thrusting
and around the corner on the south face are the edges of the thrusted
beds all dipping inward at about 30 degrees. |
Access to Dolfawr is by public footpaths of which there are various
options. The most dramatic is that following the River Unk from the
near the plantation as point 475 near which there is abundant parking.
Other routes are: south from Pantglas (some parking); NW from Edenhope
(verge parking only); and east from Upper Edenhope. |
LGS Yes. Designation proposed as these are textbook quality exposures
of folding and thrusts belonging to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1405 |
SO 243 881 |
Dolfawr (Lower
& Middle) |
Quarry (disused) |
Silurian; Ludlow Series; Bailey Hill Formation (Ref. 1) |
Exposures lie mainly on valley sides of the River Unk immediately
downstream of a river capture which changes its course from SE to NW and
from along strike to across strike. |
The identifying grid reference SOI251887 is placed adjacent to Lower
Dolfawr Farm. Exposures are alongside public footpaths and show some
degree of disturbance as folding and thrusting which are presumed to
arise from compressive forces (stress) associated with the Clun Forest
Disturbance – see Woodcock (1984). It is the view of the surveyor that
the exposures (1401-1407) are illustrative of this effect and all link
together as a single unit – albeit of appreciable scale; the most
separated exposures are 1.25 km apart. As such they warrant some
particular examination going well beyond what can be presented in this
report; here the concern is only with the location and outline
description of each exposure. At SO 243 881 the river meanders have cut
into the steep south bank causing slippage of soil and revealing bedrock
as a slightly curved steeply dipping face with an indeterminate
discontinuity higher up. It is considered here that this locality lies
at the edge of the general disturbance since no other aberrant exposure
have been found upstream of here. |
Access to Dolfawr is by public footpaths of which there are various
options. The most dramatic is that following the River Unk from the
near the plantation as point 475 near which there is abundant parking.
Other routes are: south from Pantglas (some parking); NW from Edenhope
(verge parking only); and east from Upper Edenhope. |
LGS Yes. Designation proposed as these are textbook quality exposures
of folding and thrusts belonging to the Clun Forest Disturbance |
Structure and Sedimentology/Stratigraphy |
| 1406 |
SO 513 755 |
Ludlow (Fishmore
Road Quarry) |
Quarry (disused) |
Silurian; Pridoli Series; Downtonian Stage (Ref. 1) |
On
western edge of locally high ground overlooking flood plains of rivers
Corve and Teme |
Quarry presents a 36 m long face orientated SE to NW and of a uniform
height of 6 m. The upper 4 m slope at about 40 degrees and comprise a
red silty mudstone; the bottom 2 m consist of the granular weathered
products of this mudstone forming an apron which lies at an angle of
about 30 degrees. This weathered material (angular and of a 1 to 2 mm
size) appears to derive from a process of small scale spheroidal
weathering since samples extracted from the in situ rock show rounded
surfaces. Bedding can be discerned in the upper part. This seems to be
horizontal but shows an apparent dip of about 2 degrees to the NW. In
the top 2 m are some five or so beds of a pale green-grey colour mostly
10 to 20 mm thick although the uppermost bed is nearer 50 mm. These
represent a local chemical reduction of the red ferric oxide which is
the cementing agent of the Raglan Mudstone (Ref. 2). Close examination
of the red beds reveals numbers of similar grey irregularly shaped
“reduction spots” of diameter 20 to 30 mm. It should be noted that this
exposure does not contain any sandstone or calcrete horizons so does not
demonstrate the fining upwards cyclothems which are such an important
feature of the Raglan Mudstone or its equivalent Ledbury Group in the
Church Stretton District to the north. |
Fishmore Road branches off to the north from its junction with the foot
of New Lane under the railway bridge. The quarry face will be seen on
the right some 50 m short of the bus depot. How to access to the actual
quarry face cannot be described at the time of this survey since the
large floor of the old quarry is currently subject to applications for
planning permission for major a housing complex. |
LGS Yes. Designation proposed as an exemplary exposure of the
argillaceous component of the Raglan Mudstone Formation |
Sedimentology/Stratigraphy |
| 1407 |
SO 665 743 |
Barnsland Farm
nr Cleobury Mortimer |
Quarry (active) |
Silurian; Pridoli Series; Downtonian Stage |
|
Borrow pit with spectacular calcrete fabrics colours
clay-marl-silt-sand-grit-calcareous conglmerate and possibly fish. 4 m
exposure. Also deep gully-head erosion near lustre mottled sandstone |
|
LGS Yes. Borrow pit with spectacular calcrete fabrics |
Sedimentology/Stratigraphy |
| 1408 |
SJ 489 125 |
The
"Bell-stone" in the precincts of the Morris Hall Bellstone Shrewsbury
SY1 1JB |
Erratic |
Quaternary; Devensian |
Glacial erratic of irregular shape 3 feet long and 2 feet wide and about
1 foot thick weighing probably not less than one-third of a ton; has
been moved several times within central Shrewsbury. |
A
notable boulder said in Darwin's autobiography to have probably marked a
boundary and known as the "Bell-stone". Darwin tells us that while he
was at Shrewsbury School at the age of 13 or 14 "an old Mr Cotton
[this was the Shropshire naturalist Richard Cotton
who died in 1839] in Shropshire who knew a
good deal about rocks" pointed out to me "...the 'bell-stone'; he told
me that there was no rock of the same kind nearer than Cumberland or
Scotland and he solemnly assured me that the world would come to an end
before anyone would be able to explain how this stone came where it now
lay"! Darwin adds "This produced a deep impression on me and I meditated
over this wonderful stone.". Astonishingly high powered discussion and
examination of the Bell-stone on Darwin's centenary (1909) by Bonney
Watts Harker and Fearnsides in Judd's account of the volume edited by
Seward; all six were FGS and were or became Professors and FRS!
Concluded that this was a glacial erratic (as realised by Darwin in
later life); the rock itself is a much altered andesite and was probably
derived from the Arenig district in North Wales or possibly from a point
nearer the Welsh Border by glacial action - it is NOT a 'granite' as
stated by the plaque (2008)! |
Permitted access through courtyard of the Morris Hall. |
LGS Yes. Historically important site in connection with early
influences on Charles Darwin. |
Mineralogy/Petrology |
| 1409 |
SJ 715 417 |
Dorrington Lane nr Woore |
View |
Quaternary; Devensian |
Hummocky moraine thought to coincide with limit of glacial re-advance in
Late Devensian. |
No
permanent exposures of glacial sediments but clear manifestation of
hummocky terrain including superimposed hummocks; detailed web panorama
of temporary exposure at Woore Hall Farm [SJ 721 423] at www.gigapan.org/viewGigapan.php?id=4458.
Pronounced proximal slope terrain to north and east with relief up to 15
m [SJ 715 417]; gentler distal slope terrain to south and west [SJ 723
415]. Part of the "Wrexham-Ellesmere-Wem-Whitchurch-Woore" moraine of
Clark's Glacial Map of Britain (2004). |
Public bridleway at end of Dorrington Lane. |
LGS Yes. A prominent and characteristic landscape for the extreme
northeast of Shropshire. |
Geomorphology/Landscape |
| 1410 |
SJ 603 086 |
Rushton |
Track/roadside |
Precambrian: Rushton Schists. Special Sheet 60 - Telford. |
Exposed in track bed at top of rise on to low hill (possibly downstream
edge of glacial roche moutonée)
400 m NW of Rushton village. |
Exposures of the Rushton Schists are rare and this one is revealed by
vehicle erosion across a trackway. Exposed are thinly laminated
fine-grained dark grey foliated schists with visible quartz plagioclase
and mica; possibly garnet too. Distinct lenses of coarsely crystalline
pink quartz feldspar gneissose rock giving a migmatitic expression.
Foliation very steep inclined; striking approx N-S. Thought to have
originally been subducted mudstones subsequently regionally
metamorphosed to a medium/high grade ca. 670Ma. |
Public bridleway between Rushton and Uppington. |
LGS Yes. Although a 2D exposure (in trackbed) it is one of very few
easily accessible Rushton Schists exposures. The site is easily
accessible and exposes the oldest rocks of Shropshire. |
Mineralogy/Petrology |
| 1411 |
SO 306 920 |
Owlbury |
Bank |
Quaternary; Devensian |
Series of seven low circular banks between SO 306 920 and 314 919. |
Well preserved relict periglacial cryogenic mounds ("mineral palsas")
produced by frost growth during retreat of Glacial Lake Camlad-Caebitra
accompanied by solifluction of the cores yielding circular ramparts
around depressions subsequently infilled by peat. Some of the peat has
been worked and the depressions flooded. Beware of soft spots in the
host laminated lacustrine silts and clays along the Camlad river to the
east of the road and south of Snead Church; these erupt as "mud lumps"
which can fluidise. |
On
private meadows to west of minor road; the easternmost palsas can be
seen from the roadside. |
LGS Yes. These are the best cryogenic mounds ("mineral palsas") in
Shropshire. |
Geomorphology/Landscape |
| 1412 |
SO 325 903 |
Upper Heblands |
Quarry (disused) |
Silurian intrusion |
Disused quarry immediately north of farm house; there is a second small
disused quarry and field exposures along the low ridge to the northeast. |
Microgranites intruding Wenlock mudstones. Contact is uneven hornfelsed
and brecciated. |
On
private farmland but the Shropshire Way passes 200 m to the southeast |
LGS Yes. The only acid igneous Silurian intrusion in Shropshire to
reveal the nature of its contact with the country rock. |
Mineralogy/Petrology |
| 1413 |
SJ 616 112 |
Leaton Quarry |
Quarry (active) |
Uriconian volcanogenic greywacke |
Buried sub-glacial channel |
Working aggregate and tarmac quarry in Precambrian Uriconian. Mostly
volcanogenic greywacke (andesitic) but also shatters; alterations;
rhyolites. Vestiges of pre-glacial channel in fluvioglacials. Relocated
tills in overburden (some still probably available in situ). |
Working quarry therefore permission required at all times from the
Quarry Manager; all visitors must have hard hats and high-vis jackets |
LGS Yes. Good exposure of all types of Uriconian (both stronger and
weaker); arguably the best place to see the Uriconian. |
Mineralogy/Petrology |
| 1414 |
SJ 495 095 |
Bayston Hill
Quarry |
Quarry (active) |
Precambrian; Bayston-Oakswood Group plus some Carboniferous |
Quarry excavated into a ridge underlain by the resistant Longmyndian
sediments |
A
huge quarry following the almost vertical beds and strike of the
Bayston-Oakswood Group of the Longmyndian greywackes shales and
conglomerates. The most valuable for roadstone is the greywacke which
has high skid resistance (polished surface value). To the east a quarry
extension is being made in order to allow the main quarry to go deeper.
This has revealed overlying Coal Measures in part and also glacial drift
of sand and gravels.The quarry offers a very long continuous section of
the strata which can be viewed in strike section to the north west and
across the dip at the north east end. |
Strictly only by permission of the owners. High-vis safety wear and hard
hats required. Visits must be accompanied by quarry staff. |
LGS Yes. Because it provides an awe-inspiring view in three dimensions
of the structure of the Longmyndian strata - a clear indication of their
folding and jointing visibly heading NE along strike to Haughmond Hill
and SW through Lyth Hill to the Long Mynd. To the east the
Precambrian/Carboniferous unconformity can be deduced. The track around
the SW side offers splendid views down the valley to the Stretton Hills
and Longmynd. |
Structure and Sedimentology/Stratigraphy |
| 1415 |
SJ 543 147 |
Haughmond
Quarry |
Quarry (active) |
Precambrian; Bayston-Oakswood of the Western Longmyndian |
Quarried into the flat-topped Haughmond Hill formed on a ridge of NE
trending almost vertical resistant sediments |
Haughmond is a long (800 m) deep quarry following the strike of the
coarser Western Longmyndian sediments amongst which the greywackes have
a particularly high skid resistance (polished surface value - PSV). The
quarry is now provided with an overview platform from which it is
possible to see the workings and appreciate the relationship of the
rocks along both the dip and strike faces as well as the more distant
views that show the relationship of the site to other Shropshire
landmarks. At the south west end there are interesting ice age
structures although these will be lost when quarrying extends along the
strike in that direction. |
Access into the main quarry is subject to the usual Health & Safety
regulations required for working quarries. However the provision of the
viewing platform adjacent to the south eastern boundary and accessed
from the popular Forestry Commission footpath makes this an ideal site
for displaying and explaing the geology and working of the quarry to the
general public and to school groups. |
LGS Yes. Recommended because there is such a clear relationship between
the quarry and the structure of the strata that are being quarried.
There are samples of the rock available for closer examination alongside
the adjacent public footpath. |
Structure and Sedimentology/Stratigraphy |
| 1416 |
SJ 272 246 |
Llynclys Quarry |
Quarry (active) |
Carboniferous Limestone; Brigantian |
|
Brigantian limestones and intervening lenses of dark clay (possibly
volcanic dust trapped in lagoons behind tsunami beaches - DCS; pers.
comm.). Regional dip to south east. A good variety of fossiliferous
limestones from coarse grained off-shore (with large corals) to fine
grained inter-tidal and storm beach rubble mixtures. Most ecent workings
and thickest sections to east side. West side mostly restored. Ice
wedges from periglacial conditions in Ice Age. |
With permission from owners but working quarry Health & Safety applies. |
LGS Yes. Recommended because of the exemplary exposure of Carboniferous
Limestone |
Sedimentology/Stratigraphy |
| 1417 |
SO 602 993 |
Lea Quarry |
Quarry (disused) |
Silurian; Much Wenlock Limestone Formation |
Upper part of dip-slope of Wenlock Edge |
This huge (2 km long) quarry (comprising Lea Quarry North; Lea Quarry
South and Coates Quarry) runs along the strike of the Wenlock Limestone
coming to within 10 m in parts of the crest of the Wenlock Edge
escarpment. It displays cross-sections of the Reef Knoll formations
within clearly bedded limestone including the uppermost strata of
crinoidal limestone. The sections at the south west and north east ends
clearly show the dip of the limestone. Interbedded with the limestone
are beds of bentonite ( just a centimetre or so thick - the result of
volcanic dust falls from contemporary volcanoes to the west). These also
make the rock susceptible to slippage during wet weather. Fossils are
abundant but difficult to extract from the strong limestone. Best
preservation is seen where a surface has been overlain by bentonite. |
De-registered as a working quarry but at time of designation ownership
is in negotiation between Bardon Aggregates and the National Trust. |
LGS Yes. Recommended because it provides a superb illustration
effectively in three dimensions of the highly fossiliferous Wenlock
Limestone internationally famous for its fossils and close to the
stratotype locality for the Much Wenlock Limestone Formation. |
Fossils and Sedimentology/Stratigraphy |
| 1418 |
SJ 425 325 |
Wood Lane
Quarry |
Quarry (active) |
Quaternary; Devensian superficial deposits |
Hummocky glaciofluvial landscape |
A
working sand and gravel quarry in Quaternary sediments displaying a wide
variety of periglacial and glaciofluvial material. As a working site the
detail changes with area of excavation. Restoration in part by
backfilling with waste and reseeding. Some remaining as restored pools.
Many large boulders giving examples of igneous rocks from Scotland Lake
District & North Wales. Pebbly Permo-Trias from more local Cheshire
sources. Reflects mixture of both Welsh and Irish Sea ice. |
Working quarry is area of main geological interst and subject to usual
Health & Safety regulations. Some restored parts have more free access
by arrangement with SWT and fishing interests. |
LGS Yes. Recommended because this is one of very few sites that give a
good 3D view of the drift topography of North Shropshire |
Sedimentology/Stratigraphy |
| 1419 |
SO 483 774 |
Bromfield Sand
and Gravel Quarry |
Quarry (active) |
Quaternary |
River valley with alluvial flood plain and glaciofluvial terrace |
The now extensive gravel pits operating both sides of the River Onny
display numerous sections depending on the state of current working in
the Bromfield Terrace sands and gravels (Rosenbaum; 2007). Sections
clearly illustrate the variety of conditions involved in deposition from
a braided river system in front of glaciers from the north and west.
Patches of clearly current-lain sand are often cross bedded and are
interleaved with thicker beds of very coarse gravel and conglomerate
with an imbricated texture. The pebbles and boulders of these coarse
beds clearly reflect the route of the glaciers involved. The largest
boulders are mostly of stronger rock from a greater distance - North
Wales or Lake District volcanic and igneous rocks; but a significant
number are of large well rounded or elliptical boulders which have
survived the short distance from the Llandovery (Pentamerus sandstone /
"Government Rock") outcrops in the Plowden Gorge at the southern end of
the Long Mynd or of Horderley Sandstone from the same area. The
pre-quarrying state of the River Onny is preserved between the eastern
and western areas of working. The geomorphology of the river with its
meanders flood plain and terrace can be clearly seen. |
There is no general public access since this is a registered working
quarry. However the company readily gives permission for geological
group visits subject to the usual considerations of appropriate dress
and Health & Safety. |
LGS Yes. Recommended because this is an excellent site for basic rock
type identification as well as the more detailed lessons on terrace
structure. |
Sedimentology/Stratigraphy |
