Enrichment Characteristics, Genesis, Development, and Utilization Suggestions for Metasilicic Acid in Groundwater of the Typical Black Soil Area of the Sanjiang Plain

Analyzing the hydrochemical characteristics and formation mechanism of metasilicic acid (H2SiO3) enrichment in the groundwater of Sanjiang Plain is conducive to guiding the rational development and utilization of mineral water resources in this region. Taking the groundwater in the typical black soil area of the northeastern Sanjiang Plain (from Qindeli Farm to Chuangye Farm) as an example, 104 groups of groundwater samples were collected to analyze enrichment and controlling factors of H2SiO3 by comprehensive methods such as hydrochemical analysis, rock geochemistry, water–rock interaction analysis, and ion ratio analysis. The results showed that the groundwater was generally in a reducing environment with low mineralization and weak acidity. The main cations were Ca2+ and Mg2+, and the main anion was HCO3−. The hydrochemical types were mainly HCO3–Ca and HCO3–Ca·Mg, followed by HCO3·Cl–Ca·Mg mixed type, and the H2SiO3 enrichment rate of groundwater reached 80.77%. The enrichment of H2SiO3 in the groundwater was related to the local geological structure and specific hydrogeochemical processes, and mainly controlled by the hydrolysis process of silicate rock minerals (such as albite, plagioclase, and olivine). The silicates and aluminosilicates contained in the basalt, diorite, and gneiss distributed in the area provided a rich material basis for the enrichment of H2SiO3. Its migration and distribution were simultaneously affected by leaching and cation exchange, while NO3− and SO42− input from anthropogenic sources also participated in the rock weathering, specifically the enrichment process of H2SiO3 in the groundwater. From the perspective of mineralization conditions, Qinglongshan Farm and Qindeli Farm are potential areas for developing H2SiO3-rich mineral water. However, the main direction for the development and utilization of groundwater in this area should be to explore natural H2SiO3-rich groundwater with good comprehensive water quality.