Formation of the chemical composition of brackish and brine groundwater in the Tuva depression and surrounding areas

Abstract

Abstract Groundwater with high salinity is widespread in different climatic and geologic environments of the world. The formation of its chemical composition, however, is still debatable. The chemical composition of groundwater has been studied in 19 springs of the Tuva depression. In this area, hydrocarbonate, sulfate, and chloride waters with different cation compositions discharge. Their TDS value varies mainly from 1 to 6 g/L, reaching 315 g/L at only one locality. The chemical composition of the studied waters is reflective of the geostructural, hydrogeologic, landscape, and geochemical conditions. The main processes determining the chemical composition of the waters are their interaction with aluminosilicate minerals, dissolution of gypsum and halite, evaporation, and oxidation of sulfide minerals.