矿区地下水水文地球化学研究对矿井水防治和水资源综合利用具有重要意义。针对安徽淮南煤田阜东矿区二叠系砂岩水低硫酸盐问题，通过水样采集测试，采用多元统计方法，结合水文地质条件分析和硫氧同位素技术，研究砂岩水水化学特征、水−岩作用以及低硫酸盐成因。结果表明：研究区二叠系砂岩水呈弱碱性，TDS平均值为1842.35 mg/L，属于微咸水，水化学类型主要为Cl-Na型、HCO3-Na型和Cl·HCO3-Na型。SO4 2−平均质量浓度为37.48 mg/L，明显低于淮南煤田东部潘谢矿区和淮北煤田二叠系砂岩水。主要水−岩作用为蒸发岩(氯盐岩和硫酸盐岩)和硅酸盐岩矿物溶解，存在阳离子交替吸附作用。由于边界阻水断层切割，二叠系砂岩含水层四周均为相对隔水边界，且埋藏较深，富水性弱，水动力条件较差，形成了一个封闭–半封闭的水文地质单元，具有较强的硫酸盐还原环境，有利于硫酸盐细菌还原，脱硫酸作用明显，导致δ34S升高，砂岩水硫酸盐含量偏低。研究成果可为类似条件矿区涌突水水源识别提供依据。

Hydrogeochemistry research of groundwater in coal mining areas is of great significance to the prevention and control of mine water and the comprehensive utilization of water resources. In terms of the low surfate of Permian sandstone water in Fudong mining area, Anhui Huainan Coalfield, the hydrochemical characteristics, water-rock interaction and low sulfate genesis of sandstone water were studied through water sampling and test by multivariate statistical method, in combination with the hydrogeological condition analysis and the sulfur and oxygen isotope technology. The results show that the Permian sandstone water in the study area is weakly alkaline, with an average TDS of 1 842.35 mg/L, which belongs to brackish water. The main hydrochemical types are Cl-Na type, HCO3-Na type and Cl·HCO3-Na type. The average concentration of SO4 2− is 37.48 mg/L, which is significantly lower than that Permian sandstone water in the eastern Panxie mining area of Huainan Coalfield and Huaibei Coalfield. The main water-rock interaction is evaporite (chloride and sulphate rock) and silicate minerals dissolution, with the alternating adsorption of cations. The Permian sandstone aquifer is a closed to semi-closed hydrogeological unit formed by the surrounding relative water-blocking boundary, which is cut by the boundary water-blocking fault. The aquifer is deeply buried, with weak water yield, poor hydrodynamic conditions and strong sulfate reduction environment, which is conducive to sulfate bacteria reduction. This results in obvious sulfate reduction, high δ34S and low sulfate content in the sandstone water. The research results could provide a basis for identifying the water inrush source in mining areas with similar conditions.