The Open University Geological Society Branch Newsletter

Website http://ougs.org/wessex

May 2016

Branch Organiser’s Letter CONTENTS Dear All Branch Organiser’s Letter Page 1 I hope you have all been enjoying your geology. Down Farm, , 13 March 2016 Pages 2-5 Local landslides are in the news at the moment Tedbury Camp & Vallis Vale, 28 Feb 2016 Pages 5-6 and you will find some photos of Bournemouth Bowleaze Cove, Dorset, 29 Nov 2015 Page 7 and Redcliff (above Bowleaze Cove) on pages 7 2016 AGM highlights Page 8 and 9 of this newsletter. As we point out at the A geological mystery Page 8 beginning of every field trip, we should all be Minerals guide no. 19 – Rhodochrosite Page 9 doing our own risk assessments wherever we are and highlight hazards to anyone around. Other organisations’ events Page 10

I’m certainly not going to walk along the beach Forthcoming Wessex Branch events Page 11 at or below Redcliff, and will OUGS events listing Page 12 be wary on Bournemouth prom! Wessex Branch committee Page 12 I attended Jeremy’s partner Jenny’s funeral recently. Jenny sadly lost her battle with cancer having been cared for and nursed for the and Seaton Hole on Tuesday 12th July and to past six months by Jeremy. She had a lovely see coastal defences on Wednesday tribute and farewell at a woodland burial site at 13th July. For the full list, go to http://ougs.org the edge of the New Forest. Jeremy was and click on “All events”. pleased that so many of us from OUGS as well We are fortunate to have been offered a trip to as many others were able to attend. Our Moons Hill in the Mendip Hills near Shepton thoughts are with you Jeremy. Mallet on Wednesday 17th August. Numbers are I apologise I was not able to attend the OUGS limited so contact Jeremy in good time. AGM at Scarborough in April. The main news is As well as other trips in between we also have a that Associate Members now have full voting fairly recently arranged visit to and rights. Also, a small increase in membership Wytch Farm in Dorset on Friday 7th October. fees was agreed, to take effect next year. The numbers are also limited for this. The There will be full details of these changes in the charge is more than usual as we have to hire a next OUGS Newsletter but in the meantime small coach to enter Wytch Farm, the cost of there’s a summary on page 8 of this newsletter. which will have to be divided amongst us so in Some of us are off to Mull in May on the the region of £15 to £20. We have been trying Wessex trip with Ian Williamson. The geology to gain access to Wytch Farm for a number of sounds fantastic. years and would like to thank our leader Giles Watts for this opportunity. Our next day trip is now confirmed for Saturday 11th June to a Ball Clay quarry in Purbeck, For all the Wessex trips contact Jeremy Cranmer Dorset. It is likely to be muddy so be prepared! on [email protected] The July Symposium on 8th to 10th July is now Good luck to those of you who are doing OU fully booked for residential places but day courses and are about to get into exam time. trippers are still very welcome – local You will soon have more time to join us on trips accommodation can be self-booked. There is a so you can consolidate your learning! full programme of field trips (open to all Best Wishes members) both before and after the Symposium weekend. South West Branch have Sheila Alderman, Branch Organiser Wessex organised five events in the Torbay GeoPark xxxxxxxxxxxxxxx from 3rd to 7th July. And there are two trips run Tel. xxxxxxxxxxxxxxxxx by Wessex after the Symposium: to Beer Head E-mail: [email protected]

Wessex Footnotes May 2016 Page 1 WESSEX OUGS FIELD TRIP TO DOWN FARM, DORSET, 13 MARCH 2016 Leader: Martin Green Report by Mike Bowler and Anna Pinguey Down Farm is situated in a broad downland valley at the head of the river Allen. It forms part of , rising from Wimborne to the North Dorset escarpment. The group was led on a fascinating tour of the farm by the land owner, Martin Green, a renowned archaeologist and conservationist, on a chilly but sunny day in mid-March. Having been introduced to the group, Martin summarised the history of Down Farm and its unique position in the landscape. A relatively small farm, conventional arable farming became virtually non- viable in the late 20th century. Much of the land is now used for sheep grazing, the remainder used for conservation and educational purposes. Martin is restoring the flora and associated fauna once typical of chalk downland. The whole farm is organic but nitrate levels are still significantly above the natural state due to earlier fertiliser application, and it will take many decades before the vegetation returns to its previous state. The farm contains a rich diversity of archaeological evidence resulting from human occupation after the last Ice Age, with Mesolithic, Neolithic, Bronze Age, Roman and modern features and artefacts in abundance. Martin explained how periglacial conditions 10-20,000 years ago influenced the local geomorphology. Drainage from the north Dorset escarpment led to rivers cutting through the chalk to form an undulating landscape. Clay with flints gradually washed out. Streams (locally known as winterbournes) still appear as the water table rises in wet periods. The land to the north is peppered with springs and, for seven years out of ten, large ponds form in the lower lying areas. Martin invited the group to his museum, which features many of the artefacts found during excavations on the farm and from other locations, to provide context for the various stages of human activity over 10,000 years, including an exhibit of human remains excavated from a Bronze Age barrow in Fir Tree Field. There is also an interesting geological section with rock and fossils collected by Martin and donated by contacts. Martin then led the group on a circuit of Fir Tree Field, a rectangular field close to the farmstead. Meltwater from the last Ice Age resulted in a number of collapse features Martin Green in his museum at Down Farm caused by dissolution through fissures in the Photo by Mike Bowler underlying rock. Subsequently these features have been infilled by natural and human activity creating a unique chronological stratification. One such feature was excavated by Martin in the 1980s; the stratification and radio carbon dating techniques have established the sequence of various natural and archaeological artefacts, giving a rich and unique record of evidence. One theory is that such natural features attracted humans to deposit artefacts as offerings, perhaps seeing the pit as an entrance to the "underworld". The excavation was abandoned when the water table made further digging impossible at a Fir Tree Field shaft Photo by Mike Bowler depth of 13m, but subsequent auguring allowed an estimate of a total depth of 25m. The excavated shaft (10m in diameter) is fenced off but access was granted and viewing enhanced by a pier allowing us to gaze into the shaft from above.

Wessex Footnotes May 2016 Page 2 The group paused to observe some mad March hares in an adjacent field. They seemed unperturbed by the group, possibly even curious. It felt like a privilege to witness such behaviour, as most such farmland is normally inaccessible to the public. Martin then showed us an excavated Bronze Age pond barrow where human remains had been cremated and buried in inverted pots, along with a cow burial. Three post holes were found from the entrance to the barrow aligned with nearby Pembury Knoll, which may have had some significance, and following the excavation Martin had erected new posts in situ to demonstrate the alignment. Smaller post holes within the barrow enclosure were also marked by new poles. Part of the pond barrow was covered by sheet flint, a natural flint layer which at the time of excavation was thought to be a man-made floor. Fir Tree Field pond barrow Across one corner of the field runs the Dorset , a Photo by Mike Bowler Neolithic monument which was constructed in two phases, running for almost 10km from Thickthorn Down in the south west to Martin Down in the north east. The Cursus consisted of two parallel chalk banks approximately 90m apart. This is the largest English Neolithic construction currently known. There are several theories about the purpose of the Cursus, and further reading is recommended. Most of the Cursus has been ploughed out, but a small ridge of the bank is still visible in this field, which a trench excavation in 1982 confirmed. At the top of a natural undulation in the same field, earlier excavations had discovered a Bronze Age barrow with a group of three crouch burials, two adults and a child. The burial sites have been marked and the remains retained in the museum. Before taking a break for lunch Martin showed the group a training dig site in an adjacent field, used annually by Southampton University. He also summarised some of the other activity hosted at Down Farm, including smelting and pottery workshops. In the afternoon, Martin entertained us with a very interesting demonstration of flint-knapping. He explained how black flint is more workable than 'chert' with its grey inclusions. Upper Greensand or

Portland cherts work well, however. The best flint (microcrystalline SiO2) is found in clay-rich over-soils, over chalk, where the water retention preserves it much better. Flint scraper tool Photo by Anna Pinguey Martin explained how flint-knapping is all about angles. The most interesting physical property of flint is the way it splits. Flint has a conchoidal fracture, like rock crystal or glass, but its fracture surfaces are not as uneven and curved. It's easier to control the direction of the splitting, and the edges are straighter. This depends a little bit on the amount of impurities, "purer" flint behaves more like glass. Chips coming off a flint can have razor sharp edges, making it suitable as a cutting tool - so it's a good idea to wear safety goggles if you work on flint! Blade with finely serrated edge Flint is worked on by percussion from a hammer stone such as a Photo by Anna Pinguey quartzite pebble, then softer tools such as antler or box-wood refine the fine edges. A human-worked piece of flint can be recognised by the conchoidal features and ripples. Edges can be re-worked to make them either sharper (for a blade) or blunter (so that the hand tool can be held). This secondary re-touch tells us that this flint piece was once used as a tool. We were reminded of a quote from the artist Grayson Perry - that the hand axe was 'the tool that begat all tools'. Martin then fashioned a rudimentary hand axe for us, as well as semi-circular scrapers and flint blades, the most skilled blade being very finely Ripple patterns typical of worked flint Photo by Anna Pinguey toothed.

Wessex Footnotes May 2016 Page 3 After the flint knapping demonstration, Martin led the group across the valley. This featured a series of periglacial undulations, known as naleds. The only other example of naleds in is in East Anglia. Naleds were formed by raging torrents of meltwater washing ice, chalk and flints into the valley where they settled and melted at differential rates in what was then a climate similar to the Arctic tundra of today. The deposits are known as coombe rock. As the permafrost melted, the water drained and dissolved the chalk below, resulting in the undulations. Martin walked across the ungrazed scrub among the naleds in the hope of disturbing a short-eared owl he had observed previously, apparently to no avail. However as Martin disappeared into the distance, the bird rewarded the group by taking flight, the landowner being the only member of the party to miss the spectacle. Nearby is a Pleistocene river cliff, formed by the same forces One member of the group mentioned that led to the naled deposits. From the top of the cliff, which that they had attended the solstice two years earlier, and having observed was traversed at either end by the cursus, one can get a someone wearing antlers, wondered if spectacular view of the sunset at the winter solstice over a they were in a "Wicker man" type long barrow on Gussage Down, which is also aligned within the scenario. Martin confessed that he banks of the original cursus, adding further evidence of the was the person with the antlers. recognition of natural and man-made features by those who built the Cursus. After a walk to the Ackling Dyke, a raised Roman Road connecting Badbury Rings near Wimborne to Old Sarum (Salisbury), which cuts diagonally across the boundary of Down Farm and the cursus, Martin led the group to two adjacent Neolithic henge enclosures on Wyke Down, a few metres above the seasonal ponds at the head of the River Allen catchment on the South East bank of the valley. One of the henges has a central pit where the excavators were expecting to find a burial, but nothing was recovered. Instead of a circular ditch, excavations revealed the henge was surrounded by 20-30 pits forming a circle, with a single causeway to allow access. There is evidence that the pits were re-cut long after the original construction. Some cremated remains excavated were believed to be from a secondary phase of human activity and not part of the original purpose of the enclosure. Martin pointed out that the henges were overlooked by two Bronze Age barrows on a "false horizon" - meaning that in the overall landscape, the barrow was in an apparently insignificant location, except when observed from the perspective of the Neolithic henges. Wyke Down Henge Photo by Mike Bowler A few metres away from the Wyke Down henges, excavations have exposed evidence of a substantial Neolithic building evidenced by a pattern of post holes. The building had been inhabited for some time as there was evidence of phased repair. The arrangement of post holes indicated a circular outer perimeter with a rectangular "room" within, marked by a concrete marker inscribed with an H to depict a hearth. Subsequent research suggests this would have been an oven, rather than a hearth. Grooved ware pottery fragments and burnt daub-like plaster have helped archaeologists to date the building to the Neolithic and the proximity of another building indicates this grouping may form the periphery of a significant settlement. This area is fenced off to protect the archaeology from grazing damage, affording botanists an opportunity to monitor the floral recovery of the site. Despite being several metres above the marshy area, Marsh Orchids are establishing themselves on the fenced off site on Wyke Down; the single specimen a decade ago increased to around 20 in 2015. The annual variation in the abundance of a marker plant, Autumn Gentian, is huge; whilst a biennial, short term weather conditions have proven to show a variation of between none at all and over a hundred plants per square metre. The group returned to the farmstead where Jeremy Cranmer gave a vote of thanks to Martin Green for his exceptional work and his generosity in giving up his time for the group. Mike Bowler and Anna Pinguey

Wessex Footnotes May 2016 Page 4 MORE PHOTOS FROM DOWN FARM Displays in Martin Green’s museum at Down Farm Left: Ammonites Right: Echinoids and other fossils Below: Hand axe from Algeria Photos by Anna Pinguey

WESSEX OUGS FIELD TRIP TO TEDBURY CAMP & VALLIS VALE, FROME, SOMERSET ON 28 FEBRUARY 2016 Leader: Alan Holiday Report by: Tony Loftus The Mendips display fascinating geology. Evidence of volcanism, deserts, tectonic events, sea level changes and pleasant scenery make the area ideal for an annual pilgrimage by Wessex OUGS. The basic geological story is shown in the table below: Quaternary Uplift. Landscape exhumed. Incision by streams reveals rock faces. Jurassic Marine transgression produces planar erosion surface. Mendips form an archipelago. Further sea level rise floods islands. Inferior Oolite limestone then deposited in shallow seas. Triassic Uplift, coal measures eroded away. Hot, dry environment. Flash floods, wadis. Erosion leads to breccia/ conglomerate in dolomitic matrix on lower slopes/valleys. Permian No rocks from this period. Carboniferous Marine transgression. Shallow tropical seas. Shales, limestones. Later, deltaic environment- quarzitic sandstones, coals. End Carboniferous Variscan Orogeny leads to uplift from the south and thrust faulting. Formation of Mendip periclines. Devonian Desert conditions. Rivers from north form Old Red Sandstone (ORS) deposits (not seen in Vallis Vale). Silurian Volcanism - tuffs, agglomerates, lavas (not visible in Vallis Vale).

Basic cross section N/S in the area of Tedbury Camp and Vallis Vale

Wessex Footnotes May 2016 Page 5 Tedbury Camp Parking at Great Elm, we walked towards the first destination, Tedbury Camp. On the way, samples of the Triassic Dolomitic Conglomerate (the BGS call it a conglomerate though clasts seem pretty angular!) attested to arid desert conditions – a red-coloured matrix with angular clasts typical of flash Triassic Dolomitic Conglomerate flood deposits. The Carboniferous Lithostrotion Photo by Tony Loftus limestone clasts contained fossils Photo by Tony Loftus such as Lithostrotion, a rugose coral. Further along, access to the dipping limestone beds allowed us to practise using compass clinometers and showed the beds dipping about 50 degrees to the north. A corrugated fault plane with calcite slickensides, chert beds and gastropod fossils also provided interest. Then it was uphill to the impressive Tedbury Camp location. Here the quarry company has removed the upper (Inferior Oolite) beds to gain access to the Carboniferous limestone but then stopped. This has left an excellent exposure of a rockground formed in the early Jurassic. Examination of the sides reveals the dipping nature of the Carboniferous limestone, though worm borings supposedly present could not be found. The wave cut platform would have been colonised by bivalves and worms with successive marine progradation and retrogradation leading to erosion and sediment deposition. When “high and dry” these bivalves and worms would die, with recolonization occurring with sea level rise. Evidence from worm borings (when seen!) allegedly demonstrates up to 7 such cycles. The overlying Inferior Oolite revealed fossils of gastropods, brachiopods and bivalves. Limestone blocks provided seats for lunch. Vallis Vale Driving a few kilometres east we proceeded towards the second leg at Vallis Vale. To the south we found an example of the Penarth Group rocks. These were laid down at the end of the Triassic and represent shallow marine facies as sea level started to rise, progressively flooding the Carboniferous limestone archipelago. A matrix of muddy limestone contained angular (ie locally derived) clasts of Carboniferous limestone and well-rounded clasts of chert - assumed to be derived from well-travelled Old Red Sandstone. Further along a thin paleosol provoked much prodding. Penarth Group conglomerate Photo by Tony Loftus De La Beche Unconformity And finally … the De La Beche Unconformity. The passage of time and events that have led to this impressive sight never fails to arouse wonder. Dipping beds of Carboniferous Vallis Vale limestone displayed fossil corals. Above this a layer of conglomerate was in turn surmounted by horizontal beds of the Jurassic Inferior Oolite. After a spell examining the exposure, we thanked our esteemed leader, Alan Holiday. His thorough preparation and comprehensive notes were typical of him and much appreciated by all.

De La Beche unconformity Photo by Tony Loftus

Tony Loftus

Wessex Footnotes May 2016 Page 6 WESSEX OUGS FIELD TRIP TO BOWLEAZE COVE, DORSET, 29 NOVEMBER 2015 Leader: Alan Holiday Report by: Michaela Feslova This trip explored Dorset rocks of the Upper Jurassic just outside of Weymouth. There was a number of trace fossils to be seen on the beach, the most abundant were the Diplocraterion parallelum trace fossils of the Corallian succession (fig. 1). It was also possible to see some feeding burrow trace fossils such as the Gyrophyllites (fig. 2). Trace fossils suggest a soft substrate for some time after the sediment was deposited and some rocks were burrowed so extensively that the original bedding was completely lost. Apart from the trace fossils there were also ammonites, bivalves and lignite (fossil wood) to be seen; the lignite tended to be associated with pyrite minerals, the presence of which suggests local anaerobic Fig. 1 Diplocraterion parallelum U shape burrow conditions occurred in the vicinity of the wood. trace fossil Photo by Michaela Feslova In addition to this, evidence of mass movement due to gravity (enhanced by the moisturizing effect of water) on the cliff was also examined. Further to this Osmington Oolite limestone was also analysed on the upper cliff. The oolitic texture could easily be seen as small spherical particles of sediments. These form as sand grains or shell fragments, are moved by currents in the shallow water and are coated at the same time by micrite (lime mud). There were also some examples of cross bedding, ripple marks, liesegang rings, slickensides, sandstone concretions etc. This was a highly enjoyable trip, suitable especially for those beginning geology and was accompanied by extremely high winds reaching up to 50 mph, Fig. 2 Gyrophyllites Feeding burrow trace fossil especially high up on the cliff! We were immensely Photo by Michaela Feslova lucky that the predicted rain did not arrive. Michaela Feslova BOWLEAZE COVE UPDATE – THE CRACK WIDENS! The photos below were taken by Alan Holiday on 8 and 12 April 2016, who noted that: “I have not been aware of such a rate of change on this site before.” On 13 April 2016 this section of the coast path was closed, for obvious reasons! More photos are available via the OUGS Facebook group - if you’re not already a member, e-mail [email protected] and ask to join. See also page 9 of this newsletter for a photo of the big landslide in Bournemouth on 24 April 2016.

8 April 2016 12 April 2016

Wessex Footnotes May 2016 Page 7

HIGHLIGHTS FROM THE OUGS 2016 AGM ASSOCIATE MEMBERSHIP MEMBERSHIP FEES The constitution has been changed to give associate Membership rates haven’t been increased since 2005 members the same voting rights as full members. and there is now no choice financially but to do so. From next year the rate for full and associate members Associate members may fill any post on branch will increase from £18 to £22, and that for joint committees except those of Branch Organiser and members from £26 to £32. (The £2 rate for family Branch Treasurer; they cannot serve on the OUGS members stays the same.) Executive committee. But, of course, having a vote means that associate members can now influence There will be full details of these changes in the next future policy on this! OUGS Newsletter.

NEW PRESIDENT NEW MEMBERSHIP SECRETARY Our new President is Dr Stephen Blake, a After six years of sterling service, Phyllis Turkington has volcanologist at the OU. handed over to Janet Hiscott. Janet would much appreciate it if you would amend your standing order to 2017 AGM reflect the new membership fees in good time for the renewal date of 1 January 2017. Her e-mail address is: This will be on 13 May 2017 at the Hilton Hotel in Milton Keynes. [email protected]

WHAT IS IT? A GEOLOGICAL MYSTERY The other day a friend asked me to identify a rock that he had found. I asked to see it and he produced a roundish rock that was quite a dark grey. In some lights it looked almost black to me but some said it was a dark brown. It was quite heavy for its size, but it was the surface that was really interesting. It was covered in a rectangular 'pattern' that looked like desiccation cracks. In some, well most, of the rectangles were much smaller versions but they looked like 'spider web' pattern. OK, maybe it was a crazy spider. I had never seen anything like it, so I asked him where he found it. Well, he had got it from the widow of an old rock collector who had collected rocks from all over the United States but mostly in Arizona. She had no idea where or when he had collected it. Time to do a few tests, but before that I asked everyone I could if they had seen anything like it before. The answer was unanimous; no-one had any ideas. First test - is it man made? It didn't seem so. I looked closely all over and was convinced that it was natural. If it had the pattern only on the one side, I would have thought it was weathering patterns. I have seen many 'honeycomb' type patterns in the past. But this was all around it and the 'pattern' did vary. There is no indication of "way-upness". I tried to scratch it with a coin no effect on the object. I put a few drops of dilute hydrochloric acid and it did not fizz. I tried to scratch it with a knife and it did scratch it, so I dripped a little acid into the fresh scratch - no fizz. I scrubbed it with a hard brush and washing up liquid and studied it again. The only difference is that now it has some light grey to white soap residue in the texture, so don't be fooled by that. Any ideas? Colin Morley

Wessex Footnotes May 2016 Page 8 SIMPLE GUIDE TO MINERALS 19 - by Colin Morley

RHODOCHOSITE (MnC03) As you can see from the formula, rhodochrosite is a manganese carbonate mineral. It is just that - simple MnCO3 in its pure form. It is typically a rose-red colour, but impure specimens can be shades of pink to pale brown. That's all a bit too tidy really, because sometimes other things can substitute for some manganese. This is what causes the colour to vary. If some calcium, magnesium or zinc has slipped in then the sample will be a lighter shade of the red or pink colour. This is why the most common colour is pink. Rhodochrosite occurs as a hydrothermal vein mineral along with other manganese minerals in low temperature ore deposits, as in silver mines. However, the name is derived from the Greek word meaning rose-coloured. It streaks white, and its hardness varies between 3.5 and 4. Its s.g. is between 3.5 and 3.7. It crystallizes in the trigonal system, and cleaves with rhombohedral carbonate cleavage in three directions. If I started to lose you there, just look at the picture of Crystal in the Sun City Rockhounds the crystal - it's easier; that one came from Colorado. Club Mineral Museum, Arizona, USA Photo, with permission, by Colin Morley Its main use is as an ore of manganese which is a key component of low-cost stainless steel formulations and certain aluminium alloys. Due to its relative softness and its cleavage it can be very difficult to facet, and is therefore rarely found faceted in jewellery. However the massive (occurring as a mass instead of a crystal) version is very much in demand for lapidary. Manganese carbonate messes up the amalgamation process used in the concentration of silver ores and so, until quality mineral specimens became highly sought after by collectors, they were often discarded on the mine dump. So if you are around the tailings from old silver mines - look out for anything that looks a bit Slab in the Morley Collection pink and streaks white! Photo by Colin Morley [Readers of the printed edition can see the beautiful colours of this mineral on the website. Ed.] Colin Morley

EAST CLIFF LANDSLIP HOW THE WEST WAS MADE There was a major landslip in Bournemouth on 24 April

Open University Geological Society 2016 and more expected. A lot of damage but it SYMPOSIUM 2016 happened overnight and no-one was hurt. Friday 8th to Sunday 10th July 2016

Exeter University – Streatham Campus

The Spade marks the spot

Residential places at the University are now fully booked so waiting list only. But day visitors are very welcome and there is other local accommodation still available for self-booking.

More details, including the lecture programme, field trips and other activities, are on the website, where you will also find booking forms. http://ougs.org/symposium Photo by Paul Godier (taken from a safe vantage point!)

Wessex Footnotes May 2016 Page 9 OTHER LOCAL EVENTS – PLEASE CONTACT THE ORGANISERS DIRECT

DORSET GEOLOGISTS’ ASSOCIATION GROUP (DGAG) www.dorsetgeologistsassociation.com LULWORTH RANGE WALKS 17 June 2016 Sherborne geology (Robert Chandler) & VILLAGE 23 July 2016 Chairman’s field trip and picnic, Portesham For information on opening times OUGS members welcome but check beforehand that sphaces are tel. 01929 404819 available. Contact: Doreen Smith tel. 01300 320811 or e-mail OPEN EVERY DAY OVER HOLIDAYS xxxxxxxxxxxxxxxxxxxxxx 30 April – 2 May 2016 28 May – 5 June 2016 30 July – 4 September 2016 18 December 2016 – 7 January 2017 DIGS: Dorset’s Important Geological Sites Group OPEN EVERY WEEKEND EXCEPT: More details from Alan Holiday: xxxxxxxxxxxxxxxxxxxxx 8-9 October 2016 19-20 November 2016 http://www.dorsetrigs.org.uk 10-11 December 2016 If you would like to be kept informed of forthcoming conservation sessions, please contact Alan, who will be happy to add your name to his e-mail circulation list.

BOURNEMOUTH NATURAL SCIENCE SOCIETY 39 Christchurch Road, Bournemouth BH1 3NS RUSSELL SOCIETY, SOUTHERN BRANCH http://www.bnss.org.uk http://www.russellsoc.org/ The Society covers all the branches of natural Gary Morse: xxxxxxxxxxxxxxx, tel. 01489 787300. science, including geology and palaeontology. It has For anyone interested in minerals, the Branch runs summer field an extensive, and very impressive, collection of trips plus winter lecture meetings on the second Thursday of the fossils, rocks and minerals which can be viewed, by month at Wyvern Technical College, Fair Oak, Eastleigh, Hants. appointment, on any Tuesday morning. 7 May 2016 Field trio to Hampstead Farm Quarry, Glos Forthcoming events include 18 Jun 2016 Field trip to Cavendish Mill, Derbyshire 12 Mar 2016 Plutonium(Brendan McNamara) 2 Jul 2016 Field trip to Stancombe Lane Quarry, Bristol 19 May 2016 Field trip to (Ray Chapman) For field trips, contact Chris Finch xxxxxxxxxxxxxxx 31 May 2016 Talk on copper mineralogy (Gary Morse) 23 Jun 2016 Field trip to Studland (Ray Chapman) YOUNG EXPLORERS’ CLUB (geology and more!) For children aged 7 to 12. £4 per child per meeting. SOUTHAMPTON MINERAL & FOSSIL SOCIETY 11 Jun 2016 Dinosaurs http://www.sotonminfoss.org.uk http://www.bnss.org.uk/about/young-explorers Gary Morse: xxxxxxxxxxxxxxx tel. 01489 787300 The Society runs indoor meetings, field trips and other activities relating to the collection of minerals and fossils, and the sites where they are found. Monthly evening meetings are held at The Friends' Meeting House, DORSET BUILDINGS GROUP Ordnance Road, Southampton (guests welcome). The Group aims to promote the preservation of Dorset’s building traditions and so takes a practical interest in 17 May 2017 What’s in a name? (Chris Duffin) building stones and local geology. Winter lectures (held 20-24 May 2016 Mineral collecting trip, Cornwall at Holt Village Hall, Dorset) plus summer outings. 21 Jun 2016 Cabinet of Geological Curiosities (Gary Contact: Morse) 19 Jul 2016 Collection, Conservation and Curation John and Sue Rowntree, xxxxxxxxxxxxxxx (a practical session with Gary Morse) 21 May 2016 AGM and walk around Beaminster 16 Jun 2016 Guided tour of St John the Baptist Church, Bere Regis 10 Jul 2016 Guided tour of historic Bournemouth

WINCHESTER SCIENCE FESTIVAL 4 July – 1 August 2016 Winchester Discovery Centre UNIVERSITY OF SOUTHAMPTON ROADSHOW Jewry Street, Winchester S023 8SB Summer 2016 Festival weekend is 22 -24 July 2016 Check the website for locations and dates. Keep an eye on the website for programme details. www.southampton.ac.uk/per/university/roadshow.page http://winchesterscifest.org/

Wessex Footnotes May 2016 Page 10 WESSEX BRANCH EVENTS – DETAILS

Norden, , Dorset Saturday, 11 June 2016

PURBECK BALL CLAY, WITH ANDREW DEEMING To book a place, contact: Jeremy Cranmer at [email protected] or tel. xxxxxxxxxxxxxxx

The purpose of this trip is to examine ball clay deposits and to learn about its formation, types, extraction, processing and uses. We were fortunate to have the resident geologist, Andrew Deeming, show us around in June 20XX - so a re-visit is long overdue.

The main concentration of ball clay in Dorset is to the north of the Purbeck Hills, centred on Norden. Ball clays are sedimentary in origin. Approximately 45 million years ago the climate was tropical and an ancient River washed kaolinite from its parent rock on Dartmoor. Purbeck Ball Clay has been used for thousands of years, but large scale commercial extraction began in the middle of the 18th century and continues today. Large quantities were ordered by Josiah Wedgwood from 1771 and this led to the construction of Dorset's first railway in 1806. The morning will be spent at a ball clay pit and associated restoration area, followed by a visit to the

processing works. This will involve walking 2-3 miles. As this is a working quarry, hard hats are a legal requirement. And wear boots or strong footwear, bearing in mind that clay can be very slippery when wet! In the afternoon we will visit the Ball Clay Museum at Norden. The museum tells the story of ball clay extraction on Purbeck from Roman times onwards. It has a simulated mine and a narrow gauge railway.

Beer and Seaton, Tuesday, 12 July 2016 POST-SYMPOSIUM TRIP TO BEER HEAD AND SEATON HOLE WITH ALAN HOLIDAY

To book a place, contact: Jeremy Cranmer at [email protected] or tel. xxxxxxxxxxxxxxx Alan Holiday has taught geography and geology in Weymouth since 1971 and most recently has been working at Weymouth College. He is now retired but spends much of his time leading field trips! Over the years he has been involved in a range of OUGS activities as well as now being Chairman of the DGAG and Dorset RIGS group. The aim of the trip is to study the Triassic and Cretaceous rocks and faulting which has affected them. Also to view evidence of mass-movement associated with the Hooken landslip, Seaton Hole and, if time allows, the Undercliff east of Seaton. There is a steep walk along the coastal footpath from Beer to Beer Head and a little further west to see Hooken landslip. We will walk over the shingle beach in Beer to look at the Chalk and the engineering geology associated with cliff management.

The visit to Seaton Hole (park at GR SY234896) involves walking down steps to the beach, which is rough with pebbles and boulders (tide may a problem). The total walking distance is about 3 miles. This is an area of fascinating geology and stunning views.

Lyme Regis, Dorset Wednesday, 13 July 2016 LYME REGIS COASTAL DEFENCES, WITH ALAN HOLIDAY To book a place, contact: Jeremy Cranmer at [email protected] or tel. xxxxxxxxxxxxxxx Alan Holiday has taught geography and geology in Weymouth since 1971 and most recently has been working at Weymouth College. He is now retired but spends much of his time leading field trips! Over the years he has been involved in a range of OUGS activities as well as now being Chairman of the DGAG and Dorset RIGS group. We shall study the Lower Lias of the Jurassic around Lyme Regis and view a number of developments aimed at protecting the town from the effects of mass-movement. There are steps down from the car park to the esplanade. We will walk on beach at Church Cliff, which has pebbles and boulders. The esplanade into Lyme is a flat paved area. We will continue to Monmouth Beach, which is pebbles and cobbles. The tide may or may not allow us the reach the Ammonite Graveyard east of Devonshire Head. Lyme Regis is justifiably world famous for its geology and its fossils. Originally made famous by Mary Anning and those pioneers, such as William Buckland, who worked with her. The museum is well worth a visit too.

Wessex Footnotes May 2016 Page 11 THE OPEN UNIVERSITY GEOLOGICAL SOCIETY, WESSEX BRANCH – FORTHCOMING EVENTS This listing covers events in the Wessex area and general Society events. However, members can attend events organised by any OUGS branch - the full listing is at http://ougs.org/events/ Wessex Branch field trips Places are filled on a first come, first served basis. Non-members are welcome to attend events, but members will be given priority if places are short. Please contact the organiser to confirm details and to ensure there are spaces. Packed lunches, hard hats, strong footwear and waterproofs are usually required plus reflective clothing in working quarries. Please take note of the safety issues, which the leader will outline at the start of each trip. For day trips there is usually a charge of £2.50 per person to cover expenses. Events shown in italics are joint ones – please contact the host organizer as shown. Last-minute contact on the day, if you’re not coming or late: Jeremy’s mobile 07531 318314 ONCE YOU’VE SIGNED UP FOR A WESSEX DAY TRIP, JEREMY WILL E-MAIL THE HAND-OUT TO YOU A FEW DAYS BEFORE THE EVENT SO THAT YOU CAN READ IT IN ADVANCE. DATE EVENT LEADER(S) CONTACT A week on the Isle of Mull Mark Barrett 14 – 21 May 2016 Ian Williamson (waiting list only) [email protected] Jeremy Cranmer Saturday Purbeck Ball Clay Andrew Deeming [email protected] 11 June 2016 Norden, Dorset tel. xxxxxxxxxxxxxxx OUGS OUGS Symposium, Sheila Alderman 8 – 10 July 2016 (Wessex, SW & Exeter University [email protected] Severnside) Jeremy Cranmer Tuesday Beer and Seaton Hole Alan Holiday [email protected] 12 July 2015 Devon tel. xxxxxxxxxxxxxxx Jeremy Cranmer Wednesday Lyme Regis coastal defences Alan Holiday [email protected] 13 July 2016 Dorset tel. xxxxxxxxxxxxxxx Jeremy Cranmer Wednesday Moon’s Hill Quarry, Somerset Gill Odolphie [email protected] 17 Aug 2016 (limited to 20 members) tel. xxxxxxxxxxxxxxx Kimmeridge and Wytch Farm Jeremy Cranmer Friday (limited to 20 people to share cost of Giles Watts [email protected] 7 October 2016 coach into Wytch Farm) tel. xxxxxxxxxxxxxxx London Branch AGM weekend with half- Yvonne Brett 28-30 Oct 2016 Di Smith day tours of Salisbury and Winchester xxxxxxxxxxxxxxx Beginning Geology at Bowleaze Cove Jeremy Cranmer Sunday Weymouth Alan Holiday [email protected] November 2016 (suitable for those new to field geology) tel. xxxxxxxxxxxxxxx

INFORMATION ABOUT INSURANCE ON FIELD TRIPS AND EVENTS 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. Annual travel insurance may be the best solution for any member who regularly attends field events: this again is a matter of personal choice. Please note however that all members participating in overseas events will be required to have travel insurance for the duration of the event: this is so that participants are covered for Medical, Repatriation and Personal Liability expenses. The Personal Accident element remains the personal choice of the member and again members are advised to check exclusions so that they can make an informed decision about the cover. Sheila Alderman, Branch organiser Jeremy Cranmer, Branch Day Events Organiser

WESSEX BRANCH COMMITTEE CONTRIBUTIONS TO THE Branch Organiser Sheila Alderman [email protected] NEWSLETTER Treasurer Rhiannon Rogers [email protected] Day Trip Organiser Jeremy Cranmer [email protected] Is there anything you would like to tell or ask Newsletter Editor Hilary Barton [email protected] other members? All Residential Trips Mark Barrett [email protected] contributions welcome. Website Manager Colin Morley [email protected] Librarian Jeremy Cranmer [email protected] Hilary Barton, Editor [email protected] Ordinary members: Ian Hacker, Tony Loftus, Linda Morley, Marion Phillips, Jane Mead

Wessex Footnotes May 2016 Page 12