Source and influencing factors of metasilicic acid in mixed geothermal waters

Abstract

The content of metasilicic acid in geothermal water is usually high. In this paper, the hydrochemical composition of hot springs and geothermal wells from different lithologic aquifers was studied by End-member mixing analysis, and the source and influencing factors of the H₂SiO₃ concentration in geothermal water were revealed. The results show that the H₂SiO₃ concentration in geothermal water is almost independent of the lithology of the surrounding rock at surface of hot springs and geothermal wells. Temperature is an important control factor in the H₂SiO₃ concentration of hot springs and geothermal well waters. The metasilicic acid in geothermal water mainly comes from the geothermal source water, and the mixing of a large proportion of cold water will dilute the metasilicic acid, resulting in a relatively large variation in hot springs and geothermal well waters. The mixing process evaluation gives a good overview of the fluid flow (reservoir temperature and circulation depth) within the region.