Authigenic Carbonates from Holocene Sediments of Lake Itkul (South of West Siberia) as Indicators of Climate Changes

Resumo

The results of this study on carbonate-containing bottom sediments of the shallow brackish Lake Itkul, West Siberia, are presented. The study methods applied included X-ray diffractometry (XRD), infrared spectrometry, laser granulometry, element analysis, and others. Carbonate phases are identified, and their quantitative relationships are determined by modeling of the XRD carbonate profiles using the Pearson VII function. The comparison of the carbonate record and lithological anf geochemical data on the dated sedimentary section has allowed us to reconstruct the climate-driven Holocene evolution of the lake basin. Mineralogical signals of the global climatic event known as Bond 4 are found in the territory of western Siberia.