The content of petrogenic oxides, trace elements and mineral phases in the therapeutic muds (peloids) of Lake Nukhu-Nur was determined using sedimentation columns taken in the central and coastal parts of the lake. In the center of the lake, layers with high and low contents of total sulfur (Sobshch) and S2- alternate. Sulfur is a part of sulfates: gypsum, tenardite, hexahydrite. The distribution of Sobshch is correlated with Na2O, CaO, Sr and U with strong negative correlation with other petrogenic oxides and trace elements. Layers enriched and depleted in CaO, which is correlated with Sr, are present near the shores of the lake. Lithogeochemical characteristics of peloids testify to the concentration of therapeutic components in the lake bottom sediments as a result of processes similar to weathering of rocks of acidic composition under arid climate conditions. By the ratios of petrogenic oxides and trace elements, the peloids of Lake Nukhu-Nur are generally comparable to the peloids of Udalianchi (Northeast China), coastal areas of Brazil, as well as Georgia and Spain, but are closest to the therapeutic high-sulfur sulfate muds of Copahue in Argentina.

The geochemical characteristics of Oligocene and Miocene sediments in the Khoigot paleodolinas of the Vitim Plateau have consistently changed in time, reflecting the change in sources of clastic material in the context of migratory development of the river network. The geochemical characteristics of Eocene-Miocene sediments in the eastern (Mishikhinsko-Klyuevskaya) and western (Osinovskaya) paleodolines of the Tanhoi tectonic stage of South Baikal were uniform, indicating a long-lasting input of sedimentary material from a common source. The composition of sedimentary material in the paleodolines of the Tanhoy step was controlled by a limited watershed. After the Early Pliocene structural reorganization, the geochemical characteristics of sedimentary sediments of the eastern part of the Tankhoi tectonic stage became similar to those of the Pliocene-Quaternary alluvium of the Pra-Manzurka valley of the opposite (northwestern) Baikal coast. It is assumed that Jurassic (Pra-Manzurka) and Upper Jurassic-Lower Cretaceous (eastern part of the Tanhoi tectonic stage) sedimentary rocks disintegrated and eroded on the uplifts of the Primorsky and Khamar-Daban ridges served as a common source of Pliocene-Quaternary sedimentary material.