MERCIAN Geologist Contents

MERCIAN Geologist VOLUME 18 PART 3 OCTOBER 2014 East Midlands Geological Society Contents President Vice-President Geobrowser 154 Brian Jones Tim Colman Secretary Treasurer From the Archives 156 Janet Slatter Colin Bagshaw The Record 157 Editorial Board The Record 1964 158 Tony Waltham John Carney Keith Ambrose Alan Filmer Peter Worsley 159 David Bate Duncan Short Ice-wedge growth and casting in a Late Pleistocene, Council periglacial, fluvial succession at Baston, Lincolnshire Keith Ambrose Richard Hamblin Vanessa Banks Sue Miles Stephen K. Donovan 171 David Bate Sue Cotton Palaeoecology and taphonomy of a fossil sea floor, Albert Benghiat Ian Sutton Geoff Warrington in the Carboniferous Limestone of northern England Correspondence Aron Bowers 175 Society Secretary, 100 Main Street, Further Precambrian (Ediacaran) fossil discoveries Long Whatton, Loughborough LE12 5DG in Charnwood Forest, Leicestershire 01509 843297 [email protected] Mercian Geologist Editor, Reports 11 Selby Road, Nottingham NG2 7BP Leicester brick-pits: Trevor Ford & Keith Ambrose 180 0115 981 3833 [email protected] Happisburgh footprints: Richard Hamblin 183 Mercian Geologist is printed by John Browns, and published by the East Midlands Geological Society. Landslides in the East Midlands: 185 No part of this publication may be reproduced in printed Katy Freeborough, Cath Pennington, Claire Dashwood or electronic form without prior consent of the Society. Derbyshire mineral laws: Trevor Ford 188 ISSN 0025 990X © 2014 East Midlands Geological Society Sedimentology in the Culm Basin: Ellis Elliott 189 Registered Charity No. 503617 Excursion ‒ Ticknall quarries: Keith Ambrose 190 Front cover: Creswell Crags. Photo: David Bate. Vale ‒ Richard Aldridge 193 Back cover: Panoramas in the Peak District: Ground subsidence in Mexico City: Tony Waltham 194 Mam Nick landslide into Edale, from Mam Tor; British Triassic palaeontology 36: Geoffrey Warrington 196 Castleton reef and Treak Cliff, from Back Tor; Mam Tor and the landslide road; the River Wye below Monsal Head; Supplement Chrome Hill from Parkhouse Hill. Geological Setting of the Ashover and Crich mines Photos by Tony Waltham. by Trevor D. Ford fill with water from underlying aquifers, bewaterlogged GEOBROWSER by rain, or would be naturally drained by subcropping sands. A further example of best practice was provided Geology at Flanders and Normandy by the German positions at Beaumont Hamel (Hawthorne Ridge), where the incorporation of naturally strong chalk This year sees both the centennial of the outbreak of outcrops allowed for deep, dry trench systems that were World War I and the 70th anniversary of D-Day, but virtually impregnable. On the other hand, the chalk what role, if any, did geology play in those conflicts? bedrock facilitated excellent undermining conditions In modern warfare, geology and terrain analysis are for the British, which resulted in a charge of nearly 20 essential considerations when planning a military tonnes of ammonal (ammonium nitrate and aluminium campaign (see Mercian 2000, 65-66), but this was powder) being placed beneath the German lines, causing not always the case. During the 40-day lead-up to a crater 20 m deep and 55 m wide. World War I there was hardly any time to consider geology, but that did not seem to matter when a good Learning from the lessons of World War I, geological summer ensured almost perfect battlefield conditions preparations for the D-Day landings on the Normandy in Flanders. By early October, however, heavy rainfalls beaches were thorough, and here a strong Midlands greatly hindered the movement of supplies and artillery connection was provided by the work of Quaternary on poorly drained land and an appreciation of ground geology expert, Prof. Fred Shotton of Birmingham conditions then became important. Unfortunately, University. An archive of top secret materials recently whereas basic geology had been on the syllabus of rediscovered at the university’s Lapworth Museum British military academies during the 19th century, reveals that preliminary geotechnical investigations it had been withdrawn from mainstream teaching by were carried out on a Norfolk beach with a geology the time that war broke out. The British army did not similar to that of many Normandy beaches. Geological have a professional geologist in place until 1915, and maps of the Normandy coastline were prepared, by the end of the war there were just three full-time showing geographical features including rivers and officer-geologists (Geol. Soc. Special Publication 362, gradients, with numerous notes in red ink (www. 2012). By contrast, the Germans had some 250–300 culture24.org.uk). First-hand information was gained geologists, and although these were of relatively low when Shotton flew over northern France in a Mosquito rank, they had the additional advantage of geological aircraft modified with a glass observation panel in information obtained from the libraries and offices of the base of the fuselage, while under his direction the Belgian towns and cities that they had occupied. clandestine visits were also made to sample Normandy beach sands and other deposits for their geotechnical Geological factors began to loom large when the properties. On one such visit, an auger was accidentally appalling casualties suffered during trench warfare left behind, and so to cover up this potential give-away prompted the advent of offensive (and defensive) it was planned to drop augers on every beach between tunnelling. Tunnelling techniques in association with Norway and Biscay; however, it was soon realised siege warfare would have been well known, from that there were not enough augers available to do this. examples documented in ancient China between Shotton’s involvement continued after the landings, with 481 and 221 BC, and later in medieval Britain and investigations into water supplies needed for camps in France, where battlements were typically undermined Northern France, the location of new airfields and the from tunnels with entrances concealed within trench likely problems in crossing the Meuse and the Rhine. systems. Although the Germans were the first to tunnel offensively, in 1914, by mid-1916 the British army Earthquakes illuminated had about 25,000 trained tunnellers, and whereas Remarkable luminous phenomena known as Earthquake most accounts emphasize recruitment from mining lights (EQL’s) have been observed before or during communities, the expertise of sewer workers from the earthquakes, and rarely afterwards. They can take the Manchester and London areas was also utilised for form of spheres or globes of light floating through excavating through heavy clay substrates. the air, or flame-like emanations from the ground The work of the ‘professional’ geologists in the either seconds or several days before an earthquake. British army was mainly concerned with assessment Notable examples were seen in the town of L’Aquila of groundwater supplies and the siting of mine, trench in Italy, seconds before the 2009 earthquake; along and dugout systems. Some of the world’s first detailed the St Lawrence Seaway in Quebec, 11 days before geotechnical maps and reports originated during the the powerful 1988 earthquake; and about 100 km Passchendaele Offensive of autumn 1917, when an northwest of San Francisco just before the disastrous intense artillery bombardment pulverised terrain on 1906 earthquake. poor-draining Tertiary (Palaeogene) clays. In order to A recent review noted that 85% of EQL’s were predict infantry progress during the anticipated German observed in continental rift environments, either on counter-attack, one report investigated the behaviour of or near to sub-vertical rift faults or related transform Ypresian clay following shelling to depths up to 5 m, faults (Seismological Society of America, 2 January classifying shell holes according to whether they would 2014). Although associated with a range of earthquake 154 MERCIAN GEOLOGIST 2014 18 (3) (left) Earthquake lights from Tagish Lake, southern Yukon, Canada, around the 1st of July, probably 1972 or 1973 (exact date unknown). Estimated to be a metre in diameter, the closest orbs slowly drifted up the mountain to join the more distant ones (white arrows) (photo: Jim Conacher). (right) Tutankhamun’s scarab brooch (photo: April Holloway). magnitudes between M 3.6 and 9.2, some 80% occurred coincides with the southern sector of the Dead Sea in conjunction with magnitudes greater than 5.0. The Transform, perhaps suggesting that Moses may have authors suggested that EQL’s are related to a rapid either observed an EQL, or somehow utilised local build-up of stress prior to fault rupture, and to rapid folklore about them. Other biblical stories may have local stress changes during seismic wave propagation. been inspired by seismic phenomena: for example, These changes are believed to activate mobile electronic the partial destruction of Jericho (Joshua, Ch. 6), is charge carriers, termed ‘positive holes’, which flow commonly attributed to a severe earthquake farther swiftly along the stress gradients until, when reaching along the fault, rather than simply to loud trumpeting. the surface, they ionize air molecules producing the observed luminosities. Support for this mechanism Comets and pharaohs comes from eyewitness accounts and security cameras A link between ancient religious beliefs and cosmology that captured a large number of light flashes during the is evoked by the large specimen of polished yellow- magnitude

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