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| Titel |
Reconstructing Glacial Lake Vitim and its cataclysmic drainage to the Arctic Ocean |
| VerfasserIn |
Martin Margold, John D. Jansen, Artem L. Gurinov, Alexandru T. Codilean, Frank Preusser |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250078173
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| Zusammenfassung |
| A large glacial lake (23500 km2/3000 km3) was formed when the River Vitim, one of the
largest tributaries of the Lena River in Siberia, Russia, was blocked by glaciers from the
Kodar Mountains. This lake, Glacial Lake Vitim, was subsequently drained in a large outburst
flood that followed the rivers Vitim and Lena to the Arctic Ocean. Evidence of a
cataclysmic drainage was first identified in the form of a large bedrock canyon in the
area of the postulated ice dam. The enormous dimensions of this feature (6 x 2 x
0.3 km) suggest formation via a drainage event of extreme magnitude, and field
inspection downstream revealed giant bars >100 m above the valley floor, similar
to those described from cataclysmic floods elsewhere. We present chronological
constraints for the duration of the ice dam and for the timing of the flood based on
terrestrial cosmogenic nuclides and optically stimulated luminescence. Given that the
volume of Glacial Lake Vitim was significantly larger than other well known lakes
associated with cataclysmic outbursts—glacial lakes Missoula (northwestern USA) and
Chuja-Kuray (Altai Mountains, Russia)—it is pertinent to assess the possible climatic
consequences of Lake Vitim’s drainage. The outburst flood from Glacial Lake Vitim is
likely among the largest floods documented on Earth thus far. Possible impacts
include rapid change of climate and precipitation patterns in the area of the former
glacial lake, major disturbance along the flood course to the Arctic, and perhaps even
regional-scale climatic feedbacks linked to altered sea ice dynamics in the Arctic Ocean. |
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