New Siberian Islands

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New Siberian Islands.

The New Siberian Islands (Russian: 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
- which are 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 76.283° N 140.416° E 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):

Great Lyakhovsky Island (о. Большо́й Ля́ховский) 4,600 km²
Little Lyakhovsky Island (о. Ма́лый Ля́ховский) 1,325 km²
Stolbovoy Island (о. Столбово́й) 170 km²
Semyonovsky Island (о. Семёновский) 0km² (now submerged)

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:

Jeannette Island (о. Жанне́тты)
Henrietta Island (о. Генрие́тты)
Bennett Island (о. Бе́ннетта)
Vilkitsky Island (о. Вильки́цкого)
Zhokhov Island (о. Жо́хова)

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

As discussed by Digby (1926) and in 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 couple to about 35 meters (115 feet)(Dorofeev et al. 1999, Kos’ko and Trufanov 2002).

As first noted by Baron von Toll in his account of the New Siberian Islands, sizeable 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 “great masses of ice” consisting of permafrost developed in Late Pleistocene loess, solifluction deposits, and fluvial sediments (Anastasiya 1999, Makeyev et al. 2003).

[edit] 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.

[edit] 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 1808-1810 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 V. 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 Von Toll paid a further visit to this island group in the spring of 1892, accompanied only by one Cossack and three natives. He travelled over the ice in sledges drawn by dogs and reached the south coast of Lyakhov Island, where he made some very interesting discoveries.

Under a peat composed of water mosses covering what is described as the "perpetual ice" von Toll found fragments of willow and the bones of post-Tertiary mammals, like the shoulder-bone of a saber-toothed tiger. He also reported having found in a frozen, sandy clay layer, complete trees of Alnus fruticosa fifteen feet in length, with leaves and cones adhering. Lacking modern radiocarbon dating techniques, he presumed these trees dated to what he called the "mammoth period" and were proof that tree-vegetation had reached the seventy-fourth degree of latitude, three degrees farther north than it is found at the present time at this time.

More recent detailed studies, including numerous radiocarbon, uranium-thorium, and other dates, have clarified the stratigraphy and origin of the bone-bearing sediments in which Baron von Toll found abundant bones of mammoth, rhinoceros, musk-ox, and other vertebrates and the trunks of alder trees. Romanovsky (1958) and Meyer et al. (2002) found the bone- and alder-bearing sediments of Baron von Toll exposed along the coast of Bol’shoy Lyakhovsky Island to consist of Middle to Late Quaternary floodplain and thermokarst lake sediments underlying different terrace levels. Later studies determined that the alder, Alnus fruticosa, trees lived within the New Siberian Islands only during relatively brief periods of warm interstadial and interglacial climates. Makeyev et al. (2003) found that over the last 15,000 years, Alnus fruticosa occupied these islands from 12,200 to 12,500 radiocarbon years BP during an interstadial that was unrelated to von Toll's "mammoth period". Andreev et al. (2004) dated sediments containing vertebrate fossils and alder pollen and wood to the last, Kazantsevo (Eemian), Interglacial Epoch about 114 to 130 thousand years ago. Makeyev et al. (2003) and Andreev et al. (2004) found a lack of any evidence for the existence of the fifteen feet high alder trees reported by von Toll. At best, they found evidence of only dwarf alder having ever existed within the New Siberian Islands.

[edit] References

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). Boreas. vol. 33, pp. 319–348.
Bunge, A., and E. Von Toll, 1887, The Expedition to the New Siberian Islands and the Jana country, equipped by the Imperial Academy of Sciences.
Digby, B., 1926, The Mammoth and Mammoth-Hunting in North-East Siberia. D. Appleton and Company: New York, 224 pp.
Dorofeev, V.K., M.G. Blagoveshchensky, A.N. Smirnov, and V.I. Ushakov, 1999, New Siberian Island. Geological structure and metallgeny. VNIIOkeangeologia, St. Petersburg, Russia. 130 pp.
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.
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.
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.
Markham, Albert Hastings Arctic Exploration, 1895
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.
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.
Location of Nanosnyy