Hydrogeochemistry of processes of dawsonite formation

Considered is the role of dawsonite in underground water-rock system, in which water continuously dissolves endogenous minerals with parallel formation of secondary, sedimentary minerals thus leading to deep differentiation of chemical elements. Investigations were conducted within Berezovoyarskoe dawsonite mineralization located in Tomi basin. The data on dawsonite and other minerals' equilibrium with the sampled underground waters of different geochemical types show that dawsonite, as well as calcite or other secondary minerals, is a product of the water-rock system evolution and is formed at strictly particular stage of this system development, coinciding with the beginning of soda-formation process. Initiation of this stage is possible only after start of calcite precipitation, as it's calcite with whom dawsonite forms paragenetic bonds.