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New Siberia ((ロシア語:Но́вая Сиби́рь); English transliteration: ''Novaya Sibir'') is the easternmost of the Anzhu Islands, the northern subgroup of the New Siberian Islands lying between the Laptev Sea and East Siberian Sea. Its area of approximately 6,200 km² places it just outside the 100 largest islands in the world. New Siberia Island is low lying, rising to only 76 m and covered with tundra vegetation. The island is a part of the territory of the Sakha (Yakutia) Republic of Russia. The fact that this island is called "New Siberia" and is located in the "New Siberian Islands" could cause some confusion. ==Geology== New Siberia Island consists of clastic sediments ranging from Late Cretaceous to Pleistocene in age. The Late Cretaceous sediments consist of extensively folded layers of gray and greenish gray tuffaceous sand, tuffaceous silt, pebbly sand, and layers of brown coal exposed in sea cliffs along it southwest coast. The sand and silt often contain either volcanic glass, fossil plants, rhyolite pebbles, or some combination of them. Eocene sand, silt, clay, and brown coal overlies an erosional unconformity cut into the Late Cretaceous sediments. Within the northwest part of New Siberia Island, these sediments grade into clays that contain fragments of marine bivalves. Directly overlying the Eocene sediments and another erosional unconformity are sands of Oligocene and Early Miocene age. They contain thin beds of silt, mud, clay, and pebbles. These sands contain fossil plants and lagoonal, swamp, and lacustrine diatoms. These sands are overlain by Pliocene sediments consisting of layers of sand, silt, mud, peat, and pebbles.〔Fujita, K., and D.B. Cook, 1990, ''The Arctic continental margin of eastern Siberia'', in A. Grantz, L. Johnson, and J. F. Sweeney, eds., pp. 289-304, The Arctic Ocean Region. Geology of North America, vol L, Geological Society of America, Boulder, Colorado.〕〔Kos’ko, M.K., and G.V. Trufanov, 2002, (''Middle Cretaceous to Eopleistocene Sequences on the New Siberian Islands: an approach to interpret offshore seismic''. ) Marine and Petroleum Geology. vol. 19, no. 7, pp. 901–919.〕 Except for the Derevyannye Hills, Pleistocene sediments blanket almost the entire surface of New Siberia Island. These deposits consist of layers of marine sediments overlain by terrestrial sediments. The lower marine sediments are composed of three superimposed beds of marine to brackish water clay containing fossil mollusks and capped with peat. The overlying terrestrial sediments consist of an ice complex composed of ice-rich wind-blown silt in which ice wedges have developed. This ice complex accumulated over tens of thousands of years during the Late Pleistocene, through the Last Glacial Maximum, until it stopped at about 10,000 BP. During this period of tens of thousands of years, the formation of ice complex buried and preserved in permafrost an enormous number of mammoth tusks and bones and the bones of other “megafauna”.〔〔Basilyan, A., and P.A. Nikolskiy, 2002, (''Quaternary Deposits of New Siberia Island (Russian Arctic).'' ) 32nd Annual Arctic Workshop Abstracts, March 14–16, 2002, Institute of Arctic and Alpine Research, University of Colorado at Boulder.〕〔Dorofeev, V.K., M.G. Blagoveshchensky, A.N. Smirnov, and V.I. Ushakov, 1999, ''New Siberian Islands. Geological structure and metallgeny''. VNIIOkeangeologia, St. Petersburg, Russia. 130 pp. (in Russian)〕 New Siberia Island is noted for abundant upright tree trunks, logs, leaf prints, and other plant debris that occur within sediments that are exposed along sea cliffs and within the uplands of the Derevyannye Hills along its southern coast.〔Armstrong, A., 1857, ''A Personal Narrative of the Discovery of the North-west Passage : With numerous incidents of travel and adventure during nearly five years' continuous service in the Arctic regions while in search of the expedition under Sir John Franklin.'' Hurst and Blackett Publishers, London, England. 616 pp.〕〔Taylor, R. C., 1848, ''Statistics of Coal: The Geographical and Geological Distribution of Mineral Combustibles or Fossil Fuel or Mineral Combustibles or Fossil Fuel.'' J. W. Moore, Philadelphia, Pennsylvania. 754 pp.〕〔von Toll E., 1890, ''Tertiire Pflanzen der Insel Neu-Sibirien.'' In J. Schmalliausen, ed., Wissenflschaftliche Resultate der von der kaiserlichen Akademie zur. Erforschung des Jana-Landes u.s,w, ausgesandten Expedition, II, Mérn. Acad. Imp. Sci. Saint-Pétersb., 1890, 7e sér. XXXVII, no. 5.〕 Because of the abundance of exposed coalified logs and upright trunks, early explorers and paleobotanists referred to the Derevyannye Hills as either the "Wood Mountains", "Wood Hills", or "Tree Mountain".〔〔Kropotkin, P., 1900, (''Hurst and Blackett Review: Baron Toll on New Siberia and the Circumpolar Tertiary Flora.'' ) The Geographical Journal. vol. 16, no. 1, pp. 95-98.〕〔von Toll, E., and P. Kropotkin, 1989, (''Proposal for an Expedition to Sannikoff Land''. ) The Geographical Journal. vol. 12, no. 2, pp. 162-172.〕 At one time, the highly folded layers of sand, silt, mud, clay, and brown coal containing these coalified tree fossils were once thought to have accumulated during either the Miocene or Eocene Epoch.〔〔 These sediments and the fossil trunks and logs, which they contain, are now known to date to the Late Cretaceous Period (Turonian Stage).〔Klubov, B.A., A.A. Korshunov, and I.G. Badera, 1976, ''New data on coal measures of Novaya Sibir' Island, New Siberian.'' Transactions Doklady of the U.S.S.R. Academy of Sciences: Earth Science Sections. vol. 231, no. 1-6, pp. 58-60.〕 Baron Von Toll,〔 Dr. Klubov and others,〔 Dr. Dorofeev and others,〔 and other publications all demonstrate that the claims by some authors, i.e. Mr. Southall,〔Southall, J.C., 1875, ''The Recent Origin of Man, as Illustrated by Geology and the Modern Science of Pre-Historic Archaeology.'' J.B. Lippincott & Company, London, United Kingdom. 606 pp.〕 that the "Wood Hills" of New Siberia Island are either partially or completely "formed of driftwood" are completely erroneous. 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「New Siberia」の詳細全文を読む スポンサード リンク
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