The first records of climatic changes in the basin of Lake Khikushka (Eastern Sayan) in the Late Glacial Holocene

Abstract

A complex of X-ray methods was used to reconstruct the geochemical evolution in the catchment basin of high-mountain Lake Khikushka (Eastern Siberia, Russia) with the undisturbed environment: wavelength-dispersive X-ray fluorescence method was used to determine the elemental composition, and X-ray powder diffraction method was used to determine the mineral composition of the 123 cm long Khik-15 sediment core taken from a depth of 30 m. The proposed for wavelength-dispersive X-ray fluorescence analysis the fusion sample preparation technique requires a sample weighing only 110 mg, which allows analyzing each centimeter of the core and eventually achieve a uniquely high resolution of paleoclimatic reconstructions of global and regional climatic and environmental changes. Four periods of natural variability of climate, the environmental conditions, and dynamics of the relative intensity of chemical weathering over the past 14500 years in the Lake Khikushka basin were identified using cluster analysis results obtained by the Tilia program.