157 / 2023-07-05 18:34:16

Analysis of mine water source in frozen soil area based on hydrochemistry and environmental isotope

environmental isotope; headstream recognition; water chemical analysis; hydrated layer of Quaternary system; frozen soil

The seasonal freezing and thawing process of frozen soil layer has an important influence on the seepage flow, seepage direction and velocity of groundwater, which leads to the unique theory and mechanism of groundwater migration in frozen soil area. In order to study the source and recharge characteristics of mine water in the permafrost area of Shengli Coal Mine in Wujiu Coalfield, the hydrochemical characteristics and isotope distribution characteristics of mine water were analyzed by means of hydrochemical analysis and three environmental isotopes of carbon, hydrogen and oxygen. The experimental study of 7 groups of water samples show that Quaternary water, Quaternary permafrost water, mine water and bedrock fissure water all originate from atmospheric precipitation. Surface water and Quaternary water receive rapid recharge from atmospheric precipitation, while bedrock fissure water and Quaternary permafrost water receive trace recharge from shallow Quaternary water. The oxidation amount of pyrite in mined-out area is large, and there is the possibility of a small amount of CO₂ dissolved in the gas, resulting in the enrichment of ¹³C in the area. The infiltration of surface water and Quaternary water in mine water is small, which reveals that the Quaternary permafrost layer has good waterproof performance.The research results provide a basis for the prevention and control of water disasters in Shengli Coal Mine, and can also provide reference for the identification of similar mine water sources in permafrost regions.