瞬变电磁法解释煤矿地下含水构造研究—以内蒙古东明露天矿为例

内蒙古呼伦贝尔东明露天煤矿矿坑边帮地下水渗漏的问题日益严重,矿区原有的疏干降水井排水能力及效果已不能满足生产需求,同时对矿区生态环境也造成一定程度破坏。目前,对矿区周边的水文地质条件和水力联系缺乏精准全面的认识和数据。本文通过瞬变电磁法对矿区地下水渗漏较严重的西北部进行三条勘探线(77个物理点)勘查,结果表明该区存在三处视电阻率低阻异常带,判定其主要为含水断层(裂隙)所致；结合矿区地形、地层岩性与矿区地下水矿化度,对上述异常带进行了科学合理的综合解释,并结合新施工的疏干降水井抽水验证了上述异常的可靠性,为矿区后期布置疏干降水井圈定了靶区,对当地同类型矿区地下水渗漏灾害治理起到了应用示范作用。

Research on interpretation for underground water bearing structure of coal mine by Transient Electromagnetic MethodA case study in Dongming open coal mine in Inner Mongolia

Dongming open coal mine is continuously expanding, and the ground water seepage from sides of pit is becoming more serious every day. The capacity and effect of drainage wells in mining area alread can,t meet the needs of safely in production. At the same time, ground water seepage also destroys ecological envieonment of mining area to some degree. The basic reason is lack of accurate and comprehensive cognition to geohydrologic condition and hydraulic connection of mining area. The paper uses Transient Electromagnetic Method (TEM) to survey northwest part of mining area about 3 prospecting lines and 77 detecting points, where groundwater calamity is very heavy, and prove up there are three anomaly belts of low apparent resistivity, which are hydrous and transmissible water faults or fractures. The paper makes a scientific and reasonable explanation to three anomaly belts above by comprehenshive analysis of topography of mining area, stratum and lithology, and salinity of groundwater. At last, the pumping effects of new drainage wells verify the reliability of three anomaly belts. The paper appoints the target area for drainage wells and plays an exemplary role to control groundwater in similar open coal mining area in this region.