THE KEY SECTION OF THE KAZANTSEVIAN HORIZON (LATE PLEISTOCENE) IN THE ANGARA BASIN. Kh.A. Arslanov, S.A. Laukhin, A.F. Sanko, F.Yu. Velichkevich, F.E. Maksimov, V.Yu. Kuznetsov, G.N. Shilova, S.B. Chernov, Geographical Research Institute, St. Petersburg State University, S.-Petersburg, Russia, Institute of Northern Development SD RAS, Tyumen, Russia, Institute of Geological Sciences NASB, Minsk, Belarus, Trust «Aerogeology», Moscow, Russia.

It was considered since 1970 that sediments of the Bedoba alluvial section yielded ages between 47 ka in the fluvial channel facies and 24.1 ka in the secondary pond facies. Research in 2002-2003 showed that the 14C age of the secondary pond facies was 52,100±1,680 years (LU-5044), and that of oxbow-lake peat – more than 53.5-56.9 ka. The U/Th age of oxbow-lake peat is 120±13 ka. It means that sediments of the Bedoba section formed during Kazantsevian (Eemian) Interglacial time. Palaeomalacological, palaeocarpological and palynological investigations of sediments in the Bedoba section showed that fluvial channel and oxbow-lake facies had formed during the second half of the Kazantsevian Interglacial. Cooling evidences were noted in the upper part of organogenous sediments. These and all overlying alluvial sediments had been accumulated during the first half of the Zyryanian (Early Vistulian) Glaciation. Palaeomalacological and palaeobotanical data obtained are discussed in this article.