![]() Thickens north to around 40 m in north Dorset and Somerset (Penn, 1982). Generally 4 to 20 m in south Dorset and close offshore, locally thinner or thicker. In North Oxfordshire to Lincolnshire, sharp upward change (unconformity) from fine-grained sandstone (Grantham Formation) or ooidal limestone (Lincolnshire Limestone Formation where present) into mudstone, siltstone, limestone and sandstone succession of Great Oolite Group (Rutland Formation).Ġ to 106 m at outcrop. Generally transitional, but locally an erosive non-sequence marked by a hardground. In Cotswolds, change from predominantly ooidal limestone (Salperton Limestone Formation) into mudstone (Fuller's Earth Formation) or into sandy fine-grained ooidal limestone (Chipping Norton Limestone Formation) where present, of Great Oolite Group. In Dorset-Somerset, change from ooidal limestones upward into Fuller's Earth Formation mudstone with beds of finer-grained limestone. Locally (in Mendips area and at depth on the London Platform) unconformably overlies older beds including lower Lias Group, Triassic, Carboniferous and Devonian strata. Wessex Basin: passage or sharp change upwards from fine-grained sand and sandstone (Bridport Sand Formation) into limestone succession, by decrease in sand and increase in carbonate cement. Worcester Basin-East Midlands Shelf: a disconformity with a change upwards from Lias Group (mudstone with or without sand or sandstone, ferru-ooidal mudstone and limestone beds) into predominantly limestone succession as described in the lithology section. South and east Midlands to east Yorkshire: ironstone, ferruginous limestone and sandstone (Northampton Sand Formation), overlain by mudstone, sandy mudstone and siltstone-sandstone (Grantham Formation), and shell-detrital and ooidal limestone (Lincolnshire Limestone Formation). A general, but not progressive, increase in ooid content is seen northwards across the region.Ĭotswolds-Weald: varied succession of ooidal, peloidal, sandy, ferruginous and shelly limestones, with subordinate sandstone, lime-mudstone and mudstone beds (Birdlip Limestone, Aston Limestone and Salperton Limestone formations). Abundant shelly fauna including ammonites at many levels. Thinly and rubbly bedded with many non-sequences, commonly marked by well-developed hardgrounds, many probably representing considerable breaks. What are we doing about climate change?ĭorset-Somerset (Wessex Basin): Varied succession of bioclastic, peloidal, sandy, ferruginous, argillaceous, bioturbated limestones, with subordinate ooidal limestone, sandstone, limestone conglomerate, lime-mudstone and mudstone beds.Understanding carbon capture and storage.What causes the Earth’s climate to change?. ![]()
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