Yang Tingting, Xu Guangquan, Chen Kai, Sun Gui, Dang Baoquan, Liu Mancai
School of Earth and Environment, Anhui University of Science & Technology, Huainan 232001, PR China.
School of Earth and Environment, Anhui University of Science & Technology, Huainan 232001, PR China.
Sci Total Environ. 2023 Nov 20;900:165841. doi: 10.1016/j.scitotenv.2023.165841. Epub 2023 Jul 27.
Karst collapse columns (KCCs) seriously affect the mining safety of deep coal seams. This study systematically summarizes and analyzes the development of KCCs, and classifies the different development stage to identify their development stages and evolutionary process in the Huainan coalfield. The evolution models for KCC development are given, combining with the exploration strata data from boreholes, the groundwater flow data of regional field, the hydrogeochemical data from the relative aquifers of KCC, and the hydrodynamic parameters. The results show that first types of KCCs are discovered in Liuzhuang and the Pansan mine, which is broken and disorganized, with a high degree of filling and cementation, and with the low permeability and velocity, and lower storage capacity. The KCCs in the Xieqiao and Zhangji mine have various morphologies and size differences. Their internal rocks are broken and semi-cemented, with a coefficient of permeability between 0.2 and 0.5 m/d and a specific discharge between 0.1 and 0.2 L/s•m. The KCCs are located in the cone of depression and are part of a sink area with moderate water-richness, where upper and lower aquifers have close hydraulic connections with mixed water quality. The internal core of the KCCs in the Gubei Mine is close to the center of the cone of depression which is highly broken and disorganized, with a high permeability, and a specific discharge more than 1.5 L/s•m. The intensity of runoff increases as its vertical depth also increases, especially the local areas are a higher hydraulic conductivity. Based on comprehensive hydrogeological characteristics, the KCCs development is divided into three stages: growing stage, declining stage, and dead stage. According to their characteristics of different stages, a series of evolutionary processes are established. Combining the sedimentological, karstological, and hydrogeological theories, some measures have been taken for prevention and control of mine water hazard in the various developmental stages. Hence, this research not only provides a new classified approach for KCC stages, but also an essential reference for a better understanding the mechanism of water inrush of KCCs in Northern China.
岩溶陷落柱严重影响深部煤层的开采安全。本研究系统总结并分析了岩溶陷落柱的发育情况，对淮南煤田不同发育阶段进行分类，以确定其发育阶段和演化过程。结合钻孔勘探地层数据、区域场地地下水流数据、岩溶陷落柱相关含水层的水文地球化学数据以及水动力参数，给出了岩溶陷落柱发育的演化模型。结果表明，在刘庄和潘三矿发现了第一种类型的岩溶陷落柱，其破碎且杂乱，充填和胶结程度高，渗透率和流速低，储水能力低。谢桥矿和张集矿的岩溶陷落柱形态多样，大小不一。其内部岩石破碎且半胶结，渗透系数在0.2至0.5m/d之间，比流量在0.1至0.2L/s•m之间。这些岩溶陷落柱位于降落漏斗中，是中等富水区汇水区域的一部分，上下含水层水力联系密切，水质混合。顾北矿岩溶陷落柱的内部核心靠近降落漏斗中心，高度破碎且杂乱，渗透率高，比流量大于1.5L/s•m。径流强度随垂直深度增加而增大，特别是局部地区水力传导性较高。基于综合水文地质特征，将岩溶陷落柱发育分为三个阶段：生长阶段、衰退阶段和消亡阶段。根据不同阶段的特征，建立了一系列演化过程。结合沉积学、岩溶学和水文地质学理论，针对不同发育阶段采取了一系列防治矿井水害的措施。因此，本研究不仅为岩溶陷落柱阶段提供了一种新的分类方法，也为更好地理解中国北方岩溶陷落柱突水机理提供了重要参考。
