MINERALOGICAL AND CRYSTALLOCHEMICAL INDICATORS OF ENVIRONMENTAL AND CLIMATIC CHANGES IN PLEISTOCENE-HOLOCENE SEDIMENTS OF LAKE KHUBSUGUL (MONGOLIA)

Abstract

This paper presents the first data on mineral composition of Khubsugul sediments studied in core HSG-01-8. The core was taken by the Benthos gravity corer at the flattened floor in the central part of the lake during the cruise of the R/V Dybovsky. The water depth at the sampling site is 222 m; i.e., sedimentation was undisturbed by potential lake level fluctuations. The upper part of the 174-cm-long core is composed of greenish gray diatomaceous ooze grading downward into olive-gray silty clays. These sediment varieties are separated by a transitional light gray laminated layer. The reservoir-corrected 14C age obtained for the transitional layer base is 12.23 ka (14200 calendar years) [3], which corresponds to termination of the Late Pleistocene cooling and beginning of the Belling-Allerod warming.