This article presents the data of studies of ion-salt, microcomponent, gas, and isotopic compositions of water and the equilibrium calculation results for the water-rock system. The Tersinskie carbonic-acid waters are shown to be genetically close to soda waters of the Kuznetsk Basin (Kuzbass) in the zone with slowed water exchange. Taking these data into account, the concept of formation of carbonicacid mineral waters not connected with magmatic or volcanic activities in the region was developed. According to this hypothesis, carbonic acid waters are soda waters of regional occurrence, their composition being considerably changed due to CO2 introduction from the deeper zones of the Earth's crust along the zones of tectonic ruptures
