This paper presents results of an experimental study to characterize the law of mineral change of fallen rock in coal mine groundwater reservoir ant its influence on water quality. The minerals of the underground reservoir of Daliuta Coal Mine is taken as the research object. Simulation experiments were designed and conducted to simulate water–rock action in the laboratory. The mineral composition was analyzed by X-ray diffractometer (XRD), the surface morphology of the mineral was analyzed by scanning electron microscope (SEM), and the specific surface area, total pore volume and average pore diameter of the mineral were measured by fast specific surface/pore analyzer (BET). The experimental results show that the sandstone and mudstone in the groundwater reservoir of Daliuta Coal Mine account for 70% and 30%, respectively. The pore diameter is 15.62–17.55 nm, and pore volume is 0.035 cc/g. Its pore structure is a key factor in the occurrence of water–rock interaction. According to the water–rock simulation experiment, the quartz content before the water–rock action is about 34.28%, the albite is about 21.84%, the feldspar is about 17.48%, and the kaolinite is about 8.00%. After the water–rock action, they are 36.14%, 17.78%, 11.62%, and 16.75%, respectively. The content of albite and orthoclase is reduced while the content of kaolinite is increased, that is, the Na⁺ content becomes higher, and the Ca²⁺ and Mg²⁺ contents become lower. This research builds a good theoretical foundation for revealing the role of water and rock in underground coal reservoirs.

本文提出了一项实验研究的结果，以表征煤矿地下水储层中塌落岩的矿物变化规律及其对水质的影响。以大柳塔煤矿地下储层矿物为研究对象。设计并进行了模拟实验，以模拟实验室中的水岩石作用。用X射线衍射仪（XRD）分析矿物成分，用扫描电子显微镜（SEM）分析矿物的表面形态，并通过快速测定比表面积，总孔体积和平均孔径比表面积/孔分析仪（BET）。实验结果表明，大柳塔煤矿地下水储层中的砂岩和泥岩分别占70％和30％。孔径为15。62–17.55 nm，孔体积为0.035 cc / g。其孔隙结构是水-岩相互作用发生的关键因素。根据水岩模拟实验，水岩作用前的石英含量约为34.28％，钠长石约为21.84％，长石约为17.48％，高岭石约为8.00％。在水-岩作用之后，它们分别为36.14％，17.78％，11.62％和16.75％。钠长石和原长石的含量减少，而高岭石的含量增加，即钠 在水-岩作用之后，它们分别为36.14％，17.78％，11.62％和16.75％。钠长石和原长石的含量减少，而高岭石的含量增加，即钠 在水-岩作用之后，它们分别为36.14％，17.78％，11.62％和16.75％。钠长石和原长石的含量减少，而高岭石的含量增加，即钠⁺含量变高，而Ca ²⁺和Mg ²⁺含量变低。该研究为揭示水和岩石在地下煤层中的作用奠定了良好的理论基础。