Mercia Rocks
OUGS West Midlands Branch Newsletter
Issue No 2 (2014) June 2014
Examining the Upper Ludstone near Bridgnorth Shorpshire
Branch Officers Contents
Branch Organiser – Sandra Morgan Branch Organiser’s report p 2 Branch Secretary - Vacant Field trip adverts p 3 Branch Treasurer- Susan Jackson Field Trip programme 2014 p 4
Newsletter Editor – Susan Jackson Field trip report p 5 Branch Committee Random chippings from the p 8 Jo Barnett, Patrick Joyce, Ian Kelly internet Other OUGS news p 10 If you would like to join the Other items p 11 committee please do get in touch Other Society Events p 12 [email protected]
1 [email protected] Branch Organiser’s Report
Dear all,
The field trip season is now well underway, and there are plenty of interesting events to choose from!
The first of our West Midlands field trips this year took place on Sunday 23 March. This was a geological walk around Warwick University campus organised by Patrick Joyce, led by Martyn Bradley, and attended
by 8 participants. As in previous years, Martyn gave us a very knowledgeable and interesting tour. The
university campus has a variety of geological exposures dating from the Carboniferous and Permian, notably Tile Hill Mudstone, Kenilworth Sandstone, and Gibbet Hill Conglomerate. We were also able to observe drift deposits and erratic pebbles. Thank you to Patrick for organising this trip.
Our second trip, led by Alan Richardson, took place on Sunday 11 May to Quatford, Bridgnorth and Upper Ludstone, in Shropshire. This trip was attended by ten participants and used observations from the three
sites as evidence for relative chronology. This was an excellent opportunity for participants to carry out some practical geology supported by Alan’s helpful tutor ing. We developed our field recording techniques, and improved our skills in sketching, measurement, observation and analysis, while enjoying geological detective work! See the trip report in this newsletter.
The Society AGM was held in Edinburgh on 29 March. Alongside the AGM was a weekend of activities
which included the Geoff Brown memorial lecture, the Moyra Eldridge photography competition, the
Society dinner, and a choice of field trips! There is a report on the AGM in the May edition of the Society newsletter. Some main items at the AGM were the introduction of our new OUGS President, Tom Argles, Sue Vernon’s retirement as OUGS Secretary and the election of Don Cameron as incoming Secretary, and a motion, carried by the majority of delegates, to disaffiliate from OUSA. On Sunday morning I joined one
of the field trips and enjoyed a misty walk below the Forth Bridge to explore the varied geology of South Queensferry.
We have two more West Midlands branch field trips in the next few weeks. The first will take place on Wednesday 25 June, led by David Bate of BGS. This is a geological walk around Nottingham University campus, followed by a visit to the headquarters of the British Geological Survey at Keyworth. Then on
Saturday 12 July we have a visit to Earl Sterndale in Derbyshire, led by Joe Jennings. There are details of
both of these trips and an overview of our programme for the year in this newsletter.
Finally, a reminder about the Society Symposium which will be held this year at Canterbury on 15-17 August. This year’s symposium has the theme “Marine Geotales” and includes a variety of lectures and field trips. See the notice in this newsletter and detailed information on the website at http://ougs.org/society_events/details.php?id=14&&branchcode =ouc
Best wishes
Sandra
2 [email protected] Forthcoming Field Trips
Wednesday 25th June 2014
University of Nottingham ‘Rock around the Campus’ geological trail
and the
British Geological Survey, Keyworth, Nottinghamshire
Leader David Bate BGS
In the morning we will take a walk around the University of Nottingham’s ‘Rock around the Campus Geological Trail’ http://www.nottingham.ac.uk/estates/documents/groundsgeologocalwalk.pdf In the afternoon we will have a tour of the BGS site to include the Library, the National Geological Repository (core, fossil, petrology collections etc.) the National Geological records Centre and the new Geological time walk. There will also be time to visit the BGS shop. http://www.bgs.ac.uk/contacc.sites/keyworth/geological walk/home.html
Unfortunately the BGS is not open at weekends so this is a mid-week trip only. Places may be limited so please register your interest if you are thinking of attending.
Contact Sandra Morgan: [email protected]
th Saturday 12 July 2014
Earl Sterndale and Chrome Hill, Derbyshire
Leader Joe Jennings (OU tutor) Join us on a walk from the pretty upland Peak District village of Earl Sterndale via the Jericho Quarry to the famous carboniferous reef knoll at Chrome Hill.
This area gives an opportunity to look at carboniferous shelf limestone and some reef limestone, both containing associated fossil assemblages. Traces of mineralisation can also be observed. Includes some great scenery.
Contact: Susan Jackson, [email protected]
3 [email protected] Field Trip Programme 2014
If you would like to attend any WMOUGS events please contact the Trip Organiser for full details. If you have difficulty in getting there please also let the Trip Organiser know as it may be possible to arrange a lift with another participant. There is a nominal fee of £2 on day trips (unless otherwise stated) to cover leader’s expenses. Always wear appropriate clothing and boots. Please note that it is a requirement that hard hats are now worn when examining rocks faces. Yellow jackets may be required in some quarries.
Please check the branch’s website (http://ougs.org/index.php?branchcode=wmi) for the most up to date information.
Dates for your diary.
25th June British Geological Survey, Keyworth, Nottinghamshire Leader: David Bate BGS See advert for full details Contact Sandra Morgan: [email protected]
12th July Earl Sterndale and Chrome hill, Derbyshire Leader: Joe Jennings (OU tutor) See advert for full details Contact: Susan Jackson, [email protected]
20th Sept Ragged Stone Hill, South Malverns, Worcestershire Leader: John Payne Following last year’s successful trip to the Malverns John has agreed to lead us on a trip to Ragged stone hill and the surrounding area in the south of the Malvern range. Contact: Susan Jackson, [email protected]
Oct Beginners day at the Ercall Quarry, Shropshire Leader: Ian Kelly This site is perfect for beginners and the more experienced with extrusive and intrusive continental and oceanic volcanics, a very visible strike/slip fault, igneous/sedimentary contact and a half billion year old beach. Contact: Ian Kelly [email protected]
Each person attending a field meeting does so on the understanding that he/she attends at his/her own risk. The OUGS has Public Liability Insurance Cover for field and indoor meetings, but Personal Accident Cover and Personal Liability Cover remain the responsibility and personal choice of the participant.
There may be an element of appropriate cover included in house insurance or in travel insurance: although OUGS
activities are not particularly dangerous, members are advised to check whether exclusions apply to activities in which they plan to participate in case they wish to arrange further cover. An annual travel insurance may be the best solution for any member who regularly attends field events: this again is a matter of personal choice.
4 [email protected] Field Trip Report
Field trip to Quatford, Upper Ludstone and Bridgnorth Sunday 11 May 2014 Sandra Morgan
On Sunday 11 May ten participants assembled at Quatford in Shropshire to meet our leader, Alan Richardson, for a day of practical fieldwork. The aim of the day was to “develop field investigation skills, focusing on the relative dating of sedimentary formations”, in other words, making observations, recording observations, and making interpretations grounded in the evidence we had found.
The field trip focused on three locations near Bridgnorth in Shropshire. The summary circulated beforehand by Alan informed us that “The activities will involve field sketching, dip and strike measurements, lithological description and basic aspects of sedimentological logging. It will then be possible to apply the principles of superposition, cross-cutting relationships, included fragments and lithological correlation to establish a relative chronology and environmental interpretation for the three sites.” This sounded quite ambitious, especially to those of us who were not at all confident about making field sketches or using compass clinometers! But we soon found that Alan would lead us through the basics of these techniques, so that before the end of the day we were making sketches and using compass clinometers with greater confidence and competence.
Alan was very keen that we should not start with what was known about the geology of the location, because this would be likely to influence what we expected to see. Rather than give us the “answers”, he encouraged close observation and helped us to develop the skills we needed.
Location 1: A442 Road Cutting, Quatford, SO738906-7
At this location, our first task was to observe and then draw a field sketch of the road cutting exposure. Alan gave us helpful guidance for starting our sketches, asking us to observe the big picture first, and demonstrating for us on his portable whiteboard how to determine the relative width and height, draw a frame for the sketch and then outline the main features. Alan had provided us each with a copy of his Pocket Guide to Geological Field Recording which included useful advice about what
information to include in our titles, labels and scales.
After this we walked back the short distance to the roadway which led to the car park. This was at 90o to the main road, and provided a view of the same rock exposure but at right angles to the previous view.
5 [email protected] Here we made a second field sketch and measured the dip and strike. Alan gave us a demonstration of how to use a compass clinometer and helped those of us who needed assistance with our first measurements. We then turned our attention to examining a small specimen from this bed, duly recording on our sketches the position of origin of our samples. The samples from this location were red clastic rock with well- rounded well-sorted quartz grains which had a pitted surface.
We were now able to draw some tentative conclusions from the evidence we had collected so far. The red colour of the rock indicated haematite cement formed in dry conditions, and the appearance of the grains suggested deposition by wind. The structure that we had sketched showed large scale cross bedding and was likely to be a dune front. Since the dune front was dipping towards the west, it would have been produced by an easterly wind. This in turn provided a piece of evidence for the location of Britain at the time of the rock formation: our present day winds are predominantly from the west. Towards the equator the Trade winds blow from the north east. Therefore it is likely that Britain was nearer the equator when the rock was formed.
We spent a little longer at this location, walking further along the road to observe more of the cutting. We made another sketch of the exposure, measured the dip and strike again, and tried to determine the “true” dip of the formation.
Location 2: B4176 Road Cutting, Upper Ludstone, SO802951
Once again we began by observing the main features of the exposure. There was more variation here. Of particular interest were the fine grained layers with overlying coarser layers. In places the coarser layers formed small overhangs which we examined. Again, we drew field sketches and measured the dip and strike. We examined the texture of the rock, observing a repeating pattern of coarse layers grading to finer layers, perhaps suggesting seasonal variation, and coarser layers with clasts of varying sizes, some rounded and some angular.
The colour of the rock varied, red in the fine grained rocks, grey in the coarser rocks, with narrow beds of greenish rock found in places between the fine and coarse beds. We speculated that the green colour could have arisen as a result of reduction by organic matter, and some samples contained mica, suggesting formation in an aqueous environment.
The evidence suggested fluvial deposits made by a river which underwent strong seasonal variation. The fine layers suggested deposition in a low energy environment, i.e. standing water. The red colour suggested drying out, the coarse grained rock with clasts suggested a high energy environment such as a river in flood, carrying some (rounded) rocks from a distance, with other (angular) rocks ripped from local rock. There was even evidence of evaporation: a sample was tested with acid and fizzed gently, suggesting that calcite was formed at the surface before burial.
We found a few rounded aeolian grains in our samples, and postulated that these were either grains of sand which had been blown into the water, or grains which had been eroded and washed in – evidence for this second interpretation would be an unconformity.
Location 3: The Hermitage Caves, Bridgnorth, SO727934
After observing an exposure from the main road, we turned onto a footpath through a wooded area, and came to some caves. Here we could clearly see a junction between two different types of rock. The lower rock was red and of a fairly uniform texture. The upper rock was lighter and included many clasts. The boundary between the two appeared to be uneven – was this an unconformity? The evidence here was not conclusive.
We were now given a choice of paths: while the less intrepid (or more sensible?) ascended a gentle path through the woods to the triangulation point, the more intrepid followed a path past a further outcrop and then ascended a very steep climb to the triangulation point. This further outcrop provided two additional pieces of evidence. The first was a vertical-sided channel in the sandstone which had been filled by the conglomerate. However, the angle of repose of loose sand is 32-34o. This indicates that the sand was lithified and then eroded before the clast-laden sediment was laid down. The second piece of evidence was a clast of the red aeolian sandstone incorporated into the conglomerate, again providing evidence of lithification prior to erosion.
From the triangulation point, with its excellent views and very strong winds, the group descended to our final location: more caves where the junction between the two rock types was again clearly visible. This time however, we could see that some of the upper layers of the lower rock ended abruptly in a step-like appearance. This was a strong indication that the lower rock had been eroded before the upper rock had been
7 [email protected] deposited, and this, together with the previous pieces of evidence, convinced us that we had found an unconformity!
Of course, we had not been able to trace the path of each bed of rock from the three locations visited today, but the lower rock formation at the Bridgnorth caves was very similar to the formation at Quatford, while the upper clast-laden formation at the Bridgnorth caves was very similar to the clast-laden formation at Upper Ludstone. We could observe the clast-laden bed overlying the red sandstone bed at the unconformity in Location 3, and this suggested that the Quatford formation had been deposited earlier than the formation at Upper Ludstone.
There we ended our detective work for the day, and thanked Alan for leading us on an excellent field trip. We had developed our field recording techniques, improved our skills in sketching, measurement, observation and analysis, and had discovered the rewards of making interpretations based on the evidence of our detailed observations.
Random chippings from the Internet - Alan Bates
SGAP, SSSI, LGS and RIGS – A Bowl of Alphabet Soup
Sunday May 11th saw members of the Branch in search of observations (you know, EVIDENCE, data) about the red rocks around Bridgnorth in Shropshire. In addition to getting to grips with the mechanics of a compass clinometer we faced:
High speed traffic passing within a metre or two of us
A near miss with a heavy downpour (seen over the Clee Hills, not far away)
High winds, threatening to blow us off the Hermitage ridge
Attacks from dozens of individual miner bees defending their nests deep in small holes in the red sandstone. (Oh, yes. They were there. We didn’t see them but they were there. If we had just gone round the corner we would have come into contact, simple eye to compound eye, with them. Maybe they were a bit too cold to care.)
Of course, no students were harmed in the making of this field trip although the compass clinos are known to cause severe frustration!
Our noble leader, Alan Richardson, concentrated the whole day on practical field techniques and refused to be drawn on the conclusions reached by other geologists. Quite right too. He was teaching us the basic observational techniques and he kept to his brief.
It got me thinking (now becoming a rare feature of a fading mind). Where on the Internet could I find more information on the sites we visited? Surely, these sites were listed somewhere if they were such valuable locations for geological study?
They are, of course, (not much point in writing this article otherwise …) and this is where the alphabet soup in the title comes in.
8 [email protected] Over the years the need to conserve important geological sites has become more and more pressing and County Councils have a Statutory Obligation to maintain a list of important sites that need to be protected. Taking Shropshire as an example, there is a Shropshire Geodiversity Action Plan (SGAP). Those sites of National and International importance are listed as Sites of Special Scientific Interest (hence SSSI) while those of local importance are listed as Locally Important Geological and Geomorphological Sites (LGS), formerly known as RIGS (“Regionally” ditto).
In Shropshire the Shropshire Geological Society has been particularly active in identifying important sites and the information is available by: going to the Society website at http://www.shropshiregeology.org.uk/ clicking on the large map and then on the picture showing why geoconservation is needed (!), alongside “Geodiversity and Geoconservation” drop down to “Where are LGS in Shropshire?” and almost at the bottom the “searchable list of sites” gives you a large table (which can be searched using your browser to find what you want) and “Click here for a map” which takes you to a map of Shropshire where the individual LGS sites are marked in red.
I didn’t find the map user friendly. For example enter Quatford and it says “No Results. There are no matches for your query.” Thanks guys. However, if you know roughly where the site is located then as you increase the map magnification in the standard way you eventually get an Ordnance Survey style map with the sites marked in red “ink”. Clicking on the highlighted area gives a pop-up window with the name of the site and a link to the Table.
For each of the over 300 sites the Table has columns for:
RIGS Number: Grid reference: Locality name: Feature that makes the site “Important”: Stratigraphy: Geomorphology: Description: Notes on Access (including parking).
This gives an overview of the site. Further information can often be obtained from Google and if it is adjacent to a road (like Quatford and Upper Ludstone) then views of the site can often be found using the Street View feature of Google Maps.
If you know you are going to a RIGS/LGS site in Shropshire then this gives an overview of the location and what to look for. In addition, I use it to find new sites to visit. For example, anyone who has been on one of Ian’s field trips to the Ercall Quarries (RIGS 1022) will know about the pre-Cambrian (Uriconian) rhyolite. There are other RIGS/LGS sites where it can be found …
Of course, other counties have similar RIGS/LGS information available on the Internet. For example, the counties of Herefordshire and Worcestershire can be found on the EHT site. I found the Staffordshire site in seconds by Googling RIGS in Staffordshire.
Happy hunting!
9 [email protected] Other OUGS news For full details go to the main OUGS website
nd The 42 Annual OUGS Symposium is to be held at The University of Kent at Canterbury
over the weekend of the 15th to 17th August 2014
Geomarine Theme to include lectures and field trips
Lectures, field meetings, displays & social events. Based in Rutherford College’s modern accommodation with lectures in the nearby Woolf Lecture theatre. Disabled access throughout. Residential or Day Visitor. Non-members are welcome.
Provisional Lecture Programme
Dr. Angela Coe (OU Senior Lecturer) Introductory Lecture. Tales from the Deep Blue Sea: Detecting Earth processes from Marine sedimentary deposits.
Dr. Haydon Bailey (Network Stratigraphic Consulting Ltd) Controls on Late Cretaceous Chalk deposition in the North Sea.
Dr. Peter Balson (OU tutor) Holocene evolution of the southern North Sea.
Dr Jon Copley (National Oceanographic Centre, Southampton) Recent exploration of hydrothermal vents: what does it tell us about evolutionary history in the deep ocean? Prof. Mike Elliott (Institute of Estuarine and Coastal Studies, University of Hull) A typology for hazards & risks as vectors of change & the implications for integrated management. Prof. Alastair Fraser (Imperial College, London) Petroleum exploration of extensional basins. Prof. Phil Gibbard (Cambridge Quaternary Department of Geography) & Dr Kim Cohen (University of Utrecht) Quaternary evolution of the North Sea andEnglish Channel. Miss Heather Stewart (BGS) Shallow seafloor glacial features reveal ice streaming and re-advance of the last British Ice Sheet, offshore eastern Scotland and north-eastern England, UK.
Prof. Dave Tappin (BGS) Tsunami hazards – learning from recent events.
The Weekend package include lectures, field meetings, all meals from Friday evening to Sunday lunch, Saturday night dinner and Ceilidh. Day rates include lectures/field trips, lunch & refreshments.
Sunday night package includes Dinner, Bed & Breakfast and Quiz.
Sunday morning Field meetings
1. Bishopstone Glen to Reculver. 6. Three Microscope workshops 2. Samphire Hoe, near Dover. a) Thin-section workshop. 3. Chalk Cliffs up close, near Dover. b) Zeolites under the microscope. 4. East Wear Bay, Folkestone. c) Chalk microfossil slides & fossiliferous sands 5. Canterbury Building Stones. from Bracklesham Bay, Hants & Abbey Wood.
Follow ougs.org for updates and to download the booking form.
10 [email protected] Other items For those of you that do not subscribe to the Lapworth redevelopment project newsletter here is an extract and picture from the latest edition:-
Lapworth Museum of Geology Redevelopment Project
Project Update The final application to the Heritage Lottery Fund to support the redevelopment project has been submitted and they will know the outcome towards the end of June 2014. The Museum has been working with two design teams (Real Studios -exhibition design and Associated Architects -building design) to develop some exciting plans for the Lapworth. Below is a design image for the main hall of the redeveloped museum.
The designs also incorporate a much needed museum Education Room which will enable them to accommodate a much wider, and more diverse, range of educational and community group visits. The room will include display cases with objects to support the learning sessions but when not booked, the room will be open for other visitors to enjoy.
Themes Four key themes will be incorporated within the new galleries: 1. Evolution of life - Told in chronological order based on a geological timeline. A major sub-theme will be Environment change documenting the Midlands region through the past 500 million years. 2. Earth processes - Looking at how the Earth is dynamic and actively changing. 3. Mineral wealth - Demonstrating the beauty and aesthetic appeal of minerals and crystals, how they were formed and illustrating the central role of natural resources in the establishment and growth of the Midlands area. 4. Learning and discovery - Links to important discoveries and advances made by people from the Midlands.
A new leaflet outlining the redevelopment plans and display themes is now available. To view or download a copy please visit www.birmingham.ac.uk/lapworth and click on ‘Latest news’.
The latest issue of the free Earth Heritage magazine is now available (issue 41)
‘Earth Heritage is a magazine produced twice yearly to stimulate interest in geodiversity and a broad range of geological and landscape conservation issues within the UK and further afield. It is free to download in pdf format from the Downloads section of their site and should interest geological conservation specialists, and those involved in studying Earth and environmental sciences in universities, colleges and secondary education’. Go to www.earthheritage.org.uk
11 [email protected] Other Geological Societies in the West Midlands Please see the individual websites for events
Black Country Geological Society For further details go to www.bcgs.info Lecture meetings are held at Dudley Museum & Art Gallery, St James’s Road, Dudley, DY1 1HU, 7.30 for 8 o’clock start unless stated otherwise. Those wishing to attend field meetings please contact the Field Secretary, Andy Harrison email: [email protected])
Shropshire Geological Society Further details and to book a place go to:- www.shropshiregeology.org.uk/SGS/SGSintro.html Lectures are held at Shire Hall, Shrewsbury, commencing at 7.15pm for 7.30pm A nominal charge is levied for attendance by non-Members.
Warwickshire Geological Conservation Group Further details go to www.wgcg.co.uk/ Lectures are held monthly from September to April, Starting at 7.00pm free to WGCG members with non-members £2.00 per lecture.
North Staffordshire Group of the Geologists’ Association For further details go to www.esci.keele.ac.uk/nsgga NSGGA is the regional group of the Geologist Association North Staffordshire. The winter lecture programme takes place on the second Thursday of the month from October to March at 7.30pm. All talks are held in the William Smith Building, Keele University. Field meetings are held at approximately monthly intervals over the spring and summer.
Woolhope Naturalists Field Club For further details go to www.woolhopeclub.org.uk The geology section of the club is an affiliated member of the Geologist Association. Lectures are held in the Woolhope room, Hereford Library Broad Street. Field trip programme also available. For further information on all events email Sue Hay [email protected]
Contributions to the Newsletter are very welcome. The subject matter can be anything geological that you think other members would
like to read.
Items for inclusion in the next Newsletter, by email to:
[email protected] k by 31st August 2014