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New Siberian Islands

Coordinates: 75°16′N 145°15′E / 75.267°N 145.250°E / 75.267; 145.250
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The New Siberian Islands.
Location of the New Siberian Islands.

The New Siberian Islands (Template:Lang-ru) are an archipelago, located to the North of the East Siberian coast between the Laptev Sea and the East Siberian Sea north of the Sakha (Yakutia) Republic.

The New Siberian Islands proper, or Anzhu Islands, covering a land area of about 29,000 km², consist of

  • Kotelny Island (о. Коте́льный) 11,700 km² and
    • Faddeyevsky Island (о. Фадде́евский) 5,300 km²
    • Both linked by Bunge Land (земля́ Бу́нге) 6,200 km² (occasionally submerged by sea). Very close to Bunge Land's northwestern coast there are two islands: Zheleznyakov Island (Ostrov Zheleznyakova), right off the NW cape and, east of it, Matar Island (Ostrov Matar). Both islands are about 5 km in length.
  • Nanosnyy Island 76°16′59″N 140°24′58″E / 76.283°N 140.416°E / 76.283; 140.416 is a small island located due north off the northern bay formed by Kotelny and Bunge. It is C-shaped and only 4 km in length, but its importance lies in the fact that it is the northernmost island of the New Siberian group.
  • Novaya Sibir (о. Но́вая Сиби́рь) 6,200 km²
  • Belkovsky Island (о. Бельковский) 500 km²

To the south and nearer to the Siberian mainland lie the Lyakhovskiye Islands (6,095 km²):

The small De Long Islands (228 km²) lie to the north-east of Novaya Sibir. These islands are usually not considered as part of the New Siberian group:

The new Siberian Islands are low-lying. Their highest point is Mt. Malakatyn-Tas on Kotelny island with an elevation of 374 m.

The New Siberian Islands were once major hills within the Great Arctic Plain that once formed northern part of Late Pleistocene “Beringia” between Siberia and Alaska during the Last Glacial Maximum (Late Weichselian Epoch). These islands are what remains of about 1.6 million square kilometers of the formerly subaerial Great Arctic Plain that now lies submerged below parts of the Arctic Ocean, East Siberian Sea, and Laptev Sea. At this plain's greatest extent, sea level was 100-120 m below modern sea level and the coastline was located 700-1000 kilometers north of its current position. This plain was neither extensively glaciated during the Late Pleistocene nor the Last Glacial Maximum because it lay in the rain shadow of the Northern European ice sheet. During the frigid polar climate of the Last Glacial Maximum, 17,000 to 24,000 BP, small passive ice caps formed on the adjacent De Long Islands. Fragments of these ice caps are preserved on Jeannette, Henrietta, and Bennett Islands. Traces of former small slope and cirque glaciers in the form of buried ground ice deposits are preserved on Zhokhov Island. The Great Arctic Plain was submerged, except for the New Siberian and other isolated islands, within a relatively short time span of 7,000 years during the Early-Middle Holocene.[1][2][3]

Geology

As noted by Digby[4] and numerous later publications, this archipelago consists of a mixture of folded and faulted sedimentary and igneous rocks ranging in age from Precambrian to Pliocene. The Lyakhovsky Islands consist of a folded and faulted assemblage of Precambrian metamorphic rocks; upper Paleozoic to Triassic sandstones and shales; Jurassic to lower Cretaceous turbidites; Cretaceous granites; and ophiolites. The Anzhu Islands consist of a highly faulted and folded assemblage of Ordovician to Devonian limestones, dolomites, sandstones, shales, volcanoclastic strata, and igneous rocks; upper Paleozoic to Triassic sandstones and shales; Jurassic to lower Cretaceous turbidites; and upper Cretaceous to Pliocene sandstones and shales. The De Long Islands consist of early Paleozoic, middle Paleozoic, Cretaceous, and Neogene sedimentary and igneous, mostly basalt, rocks. These sedimentary, metamorphic, and igneous rocks are mantled by loose Pleistocene and Holocene sediments that range in thickness from a fraction of a meter to about 35 meters (115 ft).[5][6]

Digby[4] also noted that some early papers published about the New Siberian Islands incorrectly describe them, often along with other Arctic islands, i.e. Wrangel Island, as being as being made either up almost entirely of mammoth bones and tusks or of ice, sand, and the bones of mammoths and other extinct megafauna. Some of these papers were written by persons, i.e. Reverend D. G. Whitney[7], who had never visited the New Siberian Islands and relied upon anecdotes of traders and travelers and local folklore for their descriptions of them, and other articles were wriitten by explorers and ivory hunters untrained in either geology or other sciences. Such statements have been shown to be fictional in nature by detailed studies of the geology of the New Siberian Islands by professional geologists, paleontologists, and other scientists including Dr. Andreev and others[8], Dr. Dorofeev and others[5], Dr. Kos’ko and Dr. Trufanov[6], Dr. Makeye and others[9], Dr. Meyer and others[10], and Dr. Romanovsky[11].

Ivory Deposits

As noted by Baron Eduard V. Toll[12] in his account of the New Siberian Islands, sizable and economically significant accumulations of fossil ivory occur within them. The ivory, along with mammoth and other bones are in found in recent beaches, drainage areas, river terraces and river beds. The New Siberian Islands are unique in the burial and preservation of fossil ivory “...in such a wonderful state of preservation that the tusks so found cannot be distinguished from the very best and purest ivory.” The abundant bones, even skeletons, of mammoth, rhinoceros, musk-ox, and other megafauna along with the mammoth ivory found in these islands are preserved by permafrost, in which they are encased. The permafrost periodically developed in Late Pleistocene loess, solifluction, pond, and stream sediments as they accumulated. The radiocarbon dating of bones, ivory, and plants; optically stimulated luminescence dating of enclosing sediments; and uranium-thorium dating of associated peats demonstrate that the bones and ivory, which are found within some of the New Siberian Islands, accumulated over a period of some 200,000 years. Their "wonderful state of preservation" is the result of them having been frozen in permafrost since their burial.[5][8][13][9]

Climate

The climate is arctic and severe. Snow cover is present for 9 months of the year.

  • Average temperature in January: −28°C to −31°C
  • Temperature in July: At the coasts icy Arctic water lets the temperatures stay relatively low. Average maximum temperatures from +8°C to +11°C and average minimum temperatures from -3°C to +1°C. In the interior of the islands the average maximum temperatures in July are +16°C to +19°C and average minimum temperatures +3°C to +6°C.
  • Precipitation: up to 132 mm a year

Permafrost and underground ice are very common. The surface of the islands is covered with Arctic tundra vegetation and numerous lakes.

History

The first news about the existence of the New Siberian Islands was brought by a Cossack Yakov Permyakov in the beginning of the 18th century. In 1712, a Cossack unit led by M. Vagin reached the Great Lyakhovsky Island. At the beginning of the 19th century, the islands were further explored by Yakov Sannikov, Matvei Gedenschtrom and others.[14]

In 1809-1810 Yakov Sannikov and Matvei Gedenschtrom went to The New Siberian Islands on a cartographic expedition. Yakov Sannikov reported the sighting of a "new land" north of Kotelny in 1811. This became the myth of Zemlya Sannikova or "Sannikov Land".[14]

In 1886 Baron Eduard von Toll, during his first visit to the New Siberian Islands thought that he had seen an unknown land north of Kotelny Island. He guessed that this was the so-called "Zemlya Sannikova".[14]

Polar explorer and scientist Baron Eduard V. Toll paid a further visit to this island group in the spring of 1892, accompanied only by one Cossack and three natives. He traveled over the ice in sledges drawn by dogs and reached the south coast of Great Lyakhovsky Island.[14] Along the southern coast of this island, Von Toll (1985), in one of his more important and interesting discoveries, found well preserved bones, ivory, peat, wood, and even a tree within 40 meter (130 feet) high sea cliffs that exposes Late Pleistocene sediments that are cemented by permafrost; have accumulated over the last 200,000 years; and overlie a Pliocene paleosol.[8][11][15] These strata are described in greater detail in the Great Lyakhovsky Island page.

References

  1. ^ Alekseev, M.N., 1997, Paleogeography and geochronology in the Russian eastern Arctic during the second half of the Quaternary. Quaternary International. vol. 41-42, pp. 11-15.
  2. ^ Anisimov, M.A., and V.E. Tumskoy, 2002, Environmental History of the Novosibirskie Islands for the last 12 ka. 32nd International Arctic Workshop, Program and Abstracts 2002. Institute of Arctic and Alpine Research, University of Colorado at Boulder, pp 23-25.
  3. ^ Schirrmeister, L., H.-W. Hubberten, V. Rachold, and V.G. Grosse, 2005, Lost world - Late Quaternary environment of periglacial Arctic shelves and coastal lowlands in NE-Siberia. 2nd International Alfred Wegener Symposium Bremerhaven, October, 30 - November 2, 2005.
  4. ^ a b Digby, B., 1926, The Mammoth and Mammoth-Hunting in North-East Siberia. D. Appleton and Company: New York, 224 pp.
  5. ^ a b c 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)
  6. ^ a b 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.
  7. ^ Whitley, D.G., 1910, The Ivory Islands of the Arctic Ocean Journal of the Transactions of the Victoria Institute. vol. XLII, pp. 35-57
  8. ^ a b c Andreev, A.A., G. Grosse, L. Schirrmeister, S.A. Kuzmina, E. Y. Novenko, A.A. Bobrov, P.E. Tarasov, B.P. Ilyashuk, T.V. Kuznetsova, M. Krbetschek, H. Meyer, and V.V. Kunitsky, 2004, Late Saalian and Eemian palaeoenvironmental history of the Bol’shoy Lyakhovsky Island (Laptev Sea region, Arctic Siberia), 3.41 MB PDF file, Boreas. vol. 33, pp. 319–348.
  9. ^ a b Makeyev, V.M., D.P. Ponomareva, V.V. Pitulko, G.M. Chernova and D.V. Solovyeva, 2003, Vegetation and Climate of the New Siberian Islands for the past 15,000 Years. Arctic, Antarctic, and Alpine Research, vol. 35, no. 1, pp. 56-66.
  10. ^ Meyer, H., A. Dereviagin, C. Siegert, L. Schirrmeister and H.-W. Hubberten, 2002, Palaeoclimate Reconstruction on Big Lyakhovsky Island, North Siberia—Hydrogen and Oxygen Isotopes in Ice Wedges. Permafrost and Periglacial processes. vol. 13, pp. 91-105.
  11. ^ a b Romanovsky, N.N., 1958, New data about the construction of Quaternary deposits on Bol’shoy Lyakhovsky Island (Novosibirsky Islands). Science College Report, Geological-Geographical Serie no. 2, pp. 243–248. (in Russian)
  12. ^ von Toll, Baron E., 1895, Wissenschaftliche Resultate der Von der Kaiserlichen Akademie der Wissenschaften sur Erforschung des Janalandes und der Neusibirischen Inseln in den Jahren 1885 und 1886 Ausgesandten expedition. [Scientific Results of the Imperial Academy of Sciences of the Investigation of Janaland and the New Siberian Islands from the Expeditions Launched in 1885 and 1886] Abtheilung III: Die fossilen Eislager und ihre Beziehungen su den Mammuthleichen. Memoires de L'Academie imperials des Sciences de St. Petersbouro, VII Serie, Tome XLII, No. 13, Commissionnaires de I'Academie Imperiale des sciences, St. Peterabourg, Russia.
  13. ^ Ivanova, A. M., V. Ushakov, G. A. Cherkashov, and A. N. Smirnov, 1999, Placer Minerals of the Russian Arctic Shelf. Polarforschung. vol. 69, pp. 163-167.
  14. ^ a b c d Markham, Albert Hastings Arctic Exploration, 1895
  15. ^ Schirrmeister, L., 2002, 230Th/U Dating of Frozen Peat, Bol’shoy LyakhovskyIsland (Northern Siberia). Quaternary Research, vol. 57, pp. 253–258

75°16′N 145°15′E / 75.267°N 145.250°E / 75.267; 145.250

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