Sediments of Lake Hovsgol as a record of paleoclimates of the Holocene andLate Pleistocene

Results of analyses of the upper sedimentary layer from Lake Hovsgol (Mongo lia) sampled with bottom cores in the Northern lake basin are presented. Th e core is characterized; the contents of moisture and biogenic silica as we ll as the composition of diatom species are determined at each 2 cm using l ight 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. Th e Holocene boundary is determined by correlation of the studied core with n umerous cores from other Mongolian lakes studied earlier. The mean sediment ation 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 Holo cene 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 deepe r insight into the sedimentary record of Lake Baikal.