New Siberian Islands

New Siberian Islands

New Siberian Islands, Rus. Novosibirskiye Ostrova, archipelago, c.10,900 sq mi (28,200 sq km), N Siberian Russia, in the Arctic Ocean between the Laptev and East Siberian seas, part of the Sakha Republic. The archipelago is separated into two groups by the Sannikov Strait. The northern group, the New Siberian or Anjou islands (c.8,200 sq mi/21,200 sq km) includes the Kotelny, Faddeyevsky, Novaya Sibir, and other smaller islands; the southern group consists of the Lyakhov Islands (c.2,700 sq mi/7,000 sq km). The De Long Islands, NE of Novaya Sibir, are also part of the archipelago. The islands are almost always covered by snow and ice and have a very scant tundra; ice dating from the Pleistocene Ice Age and intermingled with sediment is found there. The sparsely settled islands were sighted (1773) by Ivan Lyakhov, a Russian merchant. Mammoth fossils have been found (1870s) in the islands by the Swedish explorer Nils A. E. Nordenskjöld, as well as by Siberian fur and ivory hunters. The islands were neglected until 1927, when meteorological stations were set up there.

The New Siberian Islands (Новосиби́рские острова, Novosibirskiye Ostrova) 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 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 formally 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.

Geology

As noted by Digby 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).

Digby 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, 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, Dr. Dorofeev and others, Dr. Kos’ko and Dr. Trufanov, Dr. Makeye and others, Dr. Meyer and others, and Dr. Romanovsky.

Ivory Deposits

As noted by Baron Eduard V. Toll 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.

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.

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".

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".

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. 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. These strata are described in greater detail in the Great Lyakhovsky Island page.

References

External links

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