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Doggerland was an area of land, now lying beneath the southern North Sea, that connected Great Britain to mainland Europe during and after the last Ice Age. It was then gradually flooded by rising sea levels around 6,500–6,200 BCE. Geological surveys have suggested that it stretched from Britain's east coast to the Netherlands and the western coasts of Germany and the peninsula of Jutland.〔("The Doggerland Project", University of Exeter Department of Archaeology )〕 It was probably a rich habitat with human habitation in the Mesolithic period,〔(Patterson, W, "Coastal Catastrophe" (paleoclimate research document), University of Saskatchewan )〕 although rising sea levels gradually reduced it to low-lying islands before its final destruction, perhaps following a tsunami caused by the Storegga Slide.〔 The archaeological potential of the area had first been discussed in the early 20th century, but interest intensified in 1931 when a commercial trawler operating between the sandbanks and shipping hazards of the Leman Bank and Ower Bank east of the Wash dragged up a barbed antler point that dated to a time when the area was tundra. Vessels have dragged up remains of mammoth, lion and other land animals, and small numbers of prehistoric tools and weapons. ==Formation== Until the middle Pleistocene, Britain was a peninsula off Europe, connected by a massive chalk anticline, the Weald–Artois Anticline across the Straits of Dover. During the Anglian glaciation, approximately 450,000 years ago, an ice sheet filled much of the North Sea, with a large proglacial lake in the southern part fed by the Rhine, Scheldt and Thames river systems. The catastrophic overflow of this lake carved a channel through the anticline, leading to the formation of the Channel River, which carried the combined Scheldt and Thames rivers into the Atlantic. It probably created the potential for Britain to become isolated from the continent during periods of high sea level, although some scientists argue that the final break did not occur until a second ice-dammed lake overflowed during the MIS8 or MIS6 glaciations, around 340,000 or 240,000 years ago. During the most recent glaciation, the Last Glacial Maximum that ended in this area around 18,000 years ago, the North Sea and almost all of the British Isles were covered with glacial ice and the sea level was about lower than it is today. After that the climate became warmer and during the Late Glacial Maximum much of the North Sea and English Channel was an expanse of low-lying tundra, around 12,000 BC extending to the modern northern point of Scotland.〔(University of Sussex, School of Life Sciences ), C1119 Modern human evolution, Lecture 6, slide 23〕 Evidence including the contours of the present seabed shows that after the first main Ice Age, the watershed between the North Sea and the English Channel extended east from East Anglia then south-east to the Hook of Holland rather than across the Strait of Dover and that the Thames, Meuse, Scheldt and Rhine joined and flowed along the English Channel dry bed as a wide slow river that flowed far before reaching the Atlantic Ocean.〔〔 At about 8000 BC the north-facing coastal area of Doggerland had a coastline of lagoons, saltmarshes, mudflats and beaches as well as inland streams, rivers, marshes and sometimes lakes. It may have been the richest hunting, fowling and fishing ground in Europe in the Mesolithic period.〔〔( Vincent Gaffney, "Global Warming and Lost Lands: Understanding the Effects of Sea Level Rise" )〕 One big river system found by 3D seismic survey was the 'Shotton River', which drained the south-east part of the Dogger Bank hill area into the east end of the Outer Silver Pit lake. It is named after Birmingham geologist Frederick William Shotton. 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「Doggerland」の詳細全文を読む スポンサード リンク
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