The chemical and isotopic compositions of thermal waters and gases in the Republic of Buryatia, Russia

Abstract

The chemical and isotopic compositions of waters and associated gases in the Republic of Buryatia are investigated in this report. Results show the thermal waters are predominantly enriched in N2. They are alkaline, low salinity and have high concentrations of HCO3-, SO42-, F, Si but low values for Ca2+, Mg2+, K+. According to isotopic composition, the thermal waters are meteoric in origin. Despite the low salinity, the thermal waters are in equilibrium with calcite, magnesite, fluorite, albite, laumontite and other minerals but are not equilibrium with respect to primary aluminosilicates. This indicates that the thermal waters and water-bearing rocks represent the equilibrium-nonequilibrium system.