Physical and chemical calculations of secondary mineralogenesis in lakes of Western Mongolia

Abstract

The detailed research of lakes chemical composition using modern methods of physical and chemical calculations of lake water interaction with various minerals gives the chance to approach from qualitatively new positions to the issue of secondary mineralogenesis and its role in water composition formation. The main aim of the study is to determine balance degree of lake water with simple salts (carbonate, sulphate, chloride) and aluminosilicate minerals.The methods used in the study: Activity of components of aqueous solutions was determined by the «HydroGeo» software package by the method of Pitzer for highly mineralized water and brines. The results: The paper introduces the equilibrium state of lake waters of Western Mongolia with carbonate, sulfate, chloride and aluminosilicate minerals. As salty lakes are subject to intensive evaporation and their salinity can reach 300 g/l and more the balance of lake waters with various minerals has a peculiar character, reaching water saturation concerning calcite, dolomite, tenardite, halite, raresoda, albite, white mica and Mgchlorite. It was ascertained that each chemical type of lakes is characterized by a certain set of mineralsin secondary phase which depends not only on lake chemical composition, but also on composition of the rocks located within theircatchment basins. The comparative analysis of real ground precipitation of lakes with settlement data showed the reliability of the received results

Keywords

• balance
• water-rock
• system
• salt lake
• Mongolia
• physical-chemical modeling