Home – Home – Jornals – Geography and Natural Resources 2020 number 4

On the basis of comprehensive geological-geomorphological investigations, we reconstructed the parameters of Verkhnean garskii Glacier and paleogeographical settings in the Verkhneangarskaya rift zone at the epoch of Pleistocene glaciations of the Stanovoi Range. Using thermoluminescence datings of deposits on the location of fossil bones of large mammals of the mammoth faunal complex (early type) in the mouth of the Tyya river (North Baikal hollow), the lateral moraine of Tyya Glacier and lacustrine-fluvial sediments of a high terrace level, we determined their Mid-Pleistocene age. Tyya Glacier of maximal Mid-Pleistocene glaciation reached the Baikal coast, the water level of which was 80-90 m higher than at present. The identified rise of the water level in Baikal in the Mid-Pleistocene led to the ingression of its waters into the Upper Angara rift valley. It was found that Churovskii and Verkhneangarskii Glaciers reached the bottom of the basin and discharged in the lake. The available data indicate a small thickness (200-250 m) of Verkhneangarskii Glacier; nevertheless, the basin developed a thick foot glacier that formed in the basin, the outer edge of which advanced as far as upper reaches of the Gonkuli river. The glacier of the second Mid-Pleistocene ice age reached the Yanchukan river basin where a terminal-moraine line up to 5-6 km wide persisted. In the Mid-Pleistocene, the fifth and sixth terraces above floodplain formed in the Upper Angara basin, the formation time of which is confirmed by data of palynological analysis, and remains of fossil spongiofauna discovered in them indicate lacustrine conditions of sedimentation.