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The Exmoor Group is a late Devonian to early Carboniferous lithostratigraphic group (a sequence of rock strata) in southwest England whose outcrop extends from Croyde in north Devon east across Exmoor to Minehead in west Somerset. The Group comprises the following formations (in stratigraphic order, i.e. the oldest at the base and the youngest at the top) the: *Pilton Mudstone Formation (Pilton Beds, Pilton Shales) *Baggy Sandstones Formation (Baggy Beds, Marwood Beds) *Upcott Slates Formation *Pickwell Down Sandstones Formation *Morte Slates Formation *Ilfracombe Slates Formation *Hangman Sandstone Formation (Hangman Grits) *Lynton Formation (Lynton Beds, Lynton Slates) Each of these divisions has been given different names by different authors in the past including, but not limited to those shown in brackets above. Some that were previously classed as 'formations' (or even in one case as a 'group') are now formally 'members'.〔http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=EXM (BGS on-line lexicon of rock units)〕〔http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=PLT (BGS on-line lexicon of rock units)〕 ==Lynton Formation== Extending east from Woody Bay, the Lynton Formation underlies the village from which the sequence is named and continues in a thin strip of country as far east as the hamlet of Oare. There is a small inlier of the Lynton Slates at the foot of the Quantock scarp at Triscombe. The formation is composed of slates and siltstones together with some sandstone. Though its base is not seen, it is believed to be between 3–400 m thick. There are fossils of brachiopods, bivalves and bryozoans present, consistent with a shallow marine depositional environment.〔British Geological Survey 1984 ''Taunton'' England and Wales sheet 295 Solid & Drift Geology. 1:50,000 scale geological map (Keyworth, Nottingham: British Geological Survey)〕〔(【引用サイトリンク】url=http://www.devon.gov.uk/geo-west-exmoor-coast-and-valley-of-the-rocks.pdf )〕 One of Devon and Exmoor's better known natural tourist attractions is Valley of the Rocks, a dry valley developed in this formation just to the west of Lynton.〔http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=LNSL (BGS on-line lexicon of rock units)〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Exmoor Group」の詳細全文を読む スポンサード リンク
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