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The Thanet Beds or Thanet Sands are Paleocene sedimentary strata found in southeast England which are 54.8 to 57.0 million years old. They are referred to, in a wider European context, as Thanetian. Due to a local discontinuity, in the south of England they lie at the bottom of the Paleogene strata, deposited unconformably above the Cretaceous Chalk and conformably beneath the Lambeth Group. They consist almost wholly of fine soft sand, very pale grey or buff, and slightly clayey. They are well exposed at Herne Bay and Pegwell Bay. At Herne Bay the beds are divided as follows (top to bottom): * A layer of concretionary blocks (‘doggers') of calcareous indurated sandstone of 0.3 metre thickness * A pale grey sandstone with abundant shells 2.6 metre thickness * A layer of calcareous sandstone doggers, 0.3 metre thickness * A bedded, clayey buff sand with many shells, seen to 0.9 metre thickness. The beds are present as a layer below the London clay in North Kent and Surrey in the south and at Essex and Suffolk in the north.〔(Geology of the country around Southend and Foulness ) , R. D. Lake, 1986, British Geological Survey , Natural Environment Research Council, Page 9〕 Thanet Beds were formed in shallow seas with mainly siliciclastic sediments deposited as mud, silt, sand and gravel.〔(Geology of Britain viewer ) Thanet Sands description. Accessed April 2012〕 They seem to contain both sub tropical and tropical fauna and have a rich fossil content, both molluscs and fish.〔Holmes page 8.〕 ==References== *(Reports and Proceedings ), W Whitaker, The Geological Magazine or Monthly Journal of Geology, Volume 2, 1865, Page 215 *(Guide to the geology of London and the neighbourhood ) William Whitaker, 1901. *(Lambeth Group ) Bucks Earth Heritage Group] Accessed April 2012 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「Thanet Beds」の詳細全文を読む スポンサード リンク
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