Mineral and Physicochemical Systems of Evaporites: Geochemical and Thermodynamic Aspects

The distribution of mineral species by various systems in evaporites from Inder Lake (Kazakhstan) and Searles Lake (United States) is compared, and these localities are compared in terms of the distribution of species-defining elements. Ca, K, Na, Cl, B, and S are excess elements whose contents are high in both localities, whereas Si and Al are deficient. It is shown that comprehensive analysis of the evaporite mineralogy with selection of species-defining elements (mineral systems) can be used as an objective base for constructing quantitative physicochemical models on the formation of various types of evaporites. In addition, this approach allows a better understanding of the formation conditions of certain solid phases (including crystalline hydrates), which have been synthesized in aqueous–salt systems but have not yet been found in nature.