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: ''This article describes the geology of the ceremonial county of Merseyside which includes the City of Liverpool and the modern metropolitan boroughs of Knowsley, Sefton and St Helens which prior to 1974 were part of the historic county of Lancashire and the Metropolitan Borough of Wirral which was until then part of the historic county of Cheshire.'' The geology of Merseyside in northwest England largely consists of a faulted sequence of Carboniferous Coal Measures rocks overlain in the west by younger Triassic and Permian age sandstones and mudstones. Glaciation during the present Quaternary Period has left widespread glacial till as well as erosional landforms. Other post-glacial superficial deposits such as river and estuarine alluvium, peat and blown sand are abundant.〔British Geological Survey 1:50,000 scale geological map series sheets (England and Wales) 74, 83, 84, 96 & 97 and accompanying memoirs〕 == Carboniferous == Carboniferous rocks underlie all of Merseyside but are only exposed to the east of the north-south Boundary Fault. The sequence encountered locally comprises (in descending order, youngest at top):〔Aitkenhead et al 2002 ''British regional geology: the Pennines and adjacent areas'' (4th edn). British Geological Survey, Nottingham〕 *Warwickshire Group (formerly the 'Barren' or 'Red Measures') *Pennine Coal Measures Group (sometimes formerly the 'Productive' or 'Grey Coal Measures') * *Pennine Middle Coal Measures Formation * *Pennine Lower Coal Measures Formation *Millstone Grit Group The oldest rocks to appear at or near the surface within the county are from the Namurian Epoch. These are alternate units of sandstone ('flags' and 'grits') and mudstone with occasional coal seams (known locally as 'mines') forming a part of the Millstone Grit Group. They are brought to the surface on the eastern side of the Upholland Fault and dip eastwards beneath Billinge Hill. The full Namurian sequence hereabouts is: *''Gastrioceras subcrenatum'' marine band * *mudstone *Six Inch Mine (coal seam) * *mudstone *Sand Rock Mine (coal seam) * *mudstone *Rough Rock * *mudstone *Upper Haslingden Flags * *mudstone *Lower Haslingden Flags * *mudstone *Holcombe Brook Mine (coal seam) * *mudstone *Holcombe Brook Grit * *mudstone *Brooksbottom Grit * *mudstone Overlying the Millstone Grit sequence is the thick Westphalian sequence of sandstones, mudstones and coal seams collectively referred to as the Pennine Coal Measures Group and which forms the Lancashire Coalfield, the western part of which extends into Merseyside. The youngest Carboniferous strata in the area are the non-productive (of coal) reddened beds of the Warwickshire Group. 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「Geology of Merseyside」の詳細全文を読む スポンサード リンク
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