The paleogeographic and stratigraphic confinement of giant floods in West Siberia in the Late Neopleistocene-Holocene
I.D. Zol'nikov a,c,, S.A. Gus'kov b,c
a Institute of Geology and Mineralogy, Siberian Branch of the RAS, 3 prosp. Akad. Koptyuga, Novosibirsk, 630090, Russia
b Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the RAS, 3 prosp. Akad. Koptyuga, Novosibirsk, 630090, Russia
c Novosibirsk State University, 2 ul. Pirogova, Novosibirsk, 630090, Russia
Keywords: Neopleistocene; Holocene; giant floods; diluvium; Altai Mountains
Pages: 143-148
Abstract
The concepts of the role of catastrophic breakthroughs of ice- and rock-dammed and thermokarst lakes in West Siberia in the Late Neopleistocene-Holocene are systematized. The Late Neopleistocene glacial maximum in the mountains and on the plain was obviously at the same time, at 90-60 ka. It has been revealed that the basal part of the Late Quaternary cyclic three-stage upper Ob' River terrace is formed by catafluvial sediments including boulder-gravels, which descend from the valley edge beneath the water line. The Early Karginian (Kharsoimian) marine layers are spatially related to the valleys of the rushed waters of ice-dammed Lake Ermakovskoe. Substantiation is given to the concept of catastrophic flows that arrived at the plain from the Pamir and Tien Shan mountains in the Holocene Optimum and carried the Aral microfauna through the Turgai trough into the Lake Chany area. Floods resulted from the breakthrough of thermokarst lakes in the north of the West Siberian plain were typical in Karginian and Holocene time. The breakthroughs of moraine-dammed basins in the Altai Mountains took place mainly in Karginian time, whereas the breakthroughs of rock-dammed lakes, in the Sartan and Holocene epochs.
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