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 A HISTORY OF STAFFORDSHIRE Kainozoic eras are met with. The history of the formations present is however replete with interest, for not only are they grandly developed, but they have attracted the attention of some of the most celebrated observers in British geology, and conclusions which have revolutionized the science have been arrived at from investigations of these rocks in the laboratory or in the field. In the following tables giving the classification and sub-divisions of the Staffordshire rock formations in descending order the results of recent investigation and re-surveys have been embodied ; where the age of certain groups remains under discussion the published opinions of the latest authorities have been adhered to. 1 TABLE OF STRATA IN STAFFORDSHIRE Period Formation Character of Material Approximate thick- ness in feet Recent Alluvium, Peat. Mud, silt, gravel, peat ; bordering streams, rivers and in hollows. up to 15 Pleistocene Old River Drift Glacial Deposits Gravel, sand, loam, etc., of ancient river terraces Pebbly loam (Ratchel), sand, gravel, clay, cave earth. up to 40 up to 130 Keuper Rhaetic. . Keuper Marl Waterstones and Lower Keuper Sandstone Grey marl and black shales Red marls with thin sand- stones (skerries), beds of rock salt and gypsum. Red and white sandstones, building stones and false-bedded red sand- stones , up to 125 up to 2,000 up to 400 1 For more detailed information the following works should be consulted : Memoirs of the Geological Survey, 'The Geology of the South Staffordshire Coalfield,' by J. Beete Jukes (1859) ; The Iron Orel of Great Britain, pts. ii. and iv., by Sir W. W. Smyth (i 862), for a description of the ironstones and for a list of fossils by J. W. Salter ; The Geology of the country round Stockfort, Maccksfield, Congleton and Leek, by E. Hull and A. H. Green (i 866) ; The Triassic and Permian Rocks of the Midland Counties of England, by E. Hull (i 869) ; The Geology of the country round Stoke-upon-Trent, by W. Gibson and C. B. Wedd (1902); The Geology of the Cheadle Coalfield, by G. Barrow (1903) ; Summaries of Progress of the Geological Survey from 1899 to 1902. A Sketch of the Geology of the Birmingham District, by Prof. C. Lapworth, Geologists' Association, 1898, gives a concise account of the stratified deposits of South Staffordshire, also a short description of the igneous rocks by Prof. W. W. Watts, and a brief summary of the ancient glaciers of the midland counties, by W. J. Harrison ; there is in addition a useful list of bibliographical refer- ences. A full account of the organic remains of the North Staffordshire Coalfield has been published by John Ward in Trans. North Staff. Inst. Min. Eng. vol. x. (1890) ; while the order and nature of the ironstones and coals are given by C. J. Homer in the Proc. Inn and Steel Inst. (1875). Several important papers treating of the local geology are scattered through the Trans. Birm. Philos. Sac., The Midland NaturaKst, and the Trans. North Staff. Field Club. The last-mentioned society publishes from time to time a bibliography by John Ward. The county includes the following maps of the Geological Survey on the scale of one inch = one mile : Sheets (Old Series) 62, N.E. Lichfield, Tamworth ; 62, N.W. Cannock Chase ; 62, S.E. Sutton Coldfield, Birmingham, Coleshill ; 62, S.W. Wolverhampton, Walsall, Dudley ; 72, N.W. Hanley, Stoke- on-Trent; 72, N.E. Ashbourne ; 72,8. W. Stafford, Stone; 72, S.E. Burton-on-Trent, Tutbury ; 72, S.E. Market Drayton, Eccleshall. Sheets (New Series) 123, Stoke-upon-Trent ; 1 10, Maccksfield.