SEDIMENTS OF LAKE HOVSGOL AS A RECORD OF PALEOCLIMATES OF THE HOLOCENE AND LATE PLEISTOCENE
A. P. Fedotov, E. V. Bezrukova, S. S. Vorob'eva, O. M. Khlystov, O. V. Levina, I. B. Mizandrontsev, G. F. Mazepova, A. R. Semenov, T. O. Zheleznyakova, S. M. Krapivina, E. P. Chebykin, and M. A. Grachev
Keywords: Climate fluctuations, Holocene, Late Pleistocene, bottom sediments, carbonate abundance, Lake Hovsgol
Pages: 384-390
Abstract
Results of analyses of the upper sedimentary layer from Lake Hovsgol (Mongolia) sampled with bottom cores in the Northern lake basin are presented. The core is characterized; the contents of moisture and biogenic silica as well as the composition of diatom species are determined at each 2 cm using light microscopy method. Palynological analysis is performed at continuous 2 cm intervals. The content of carbonate CO2 is determined at each 10 cm.
The core obtained covered the end of glaciation and the entire Holocene. The Holocene boundary is determined by correlation of the studied core with numerous cores from other Mongolian lakes studied earlier. The mean sedimentation rate in the Northern basin in the Holocene was 7-8 cm per 1000 years.
The Pleistocene sediments contain a large amount of carbonates. In the Holocene sediments their concentration decreased abruptly.
The data obtained suggest convincingly that sampling of long sedimentation cores from Lake Hovsgol and their complex analysis can give very important information about the Pleistocene paleoclimates and, in particular, a deeper insight into the sedimentary record of Lake Baikal.
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