黄河流域中上游煤炭资源的大规模开发已造成生态环境的持续恶化，掌握煤炭开采对地下水环境的影响规律有助于实现煤炭资源开发与生态环境保护协调发展，采用瞬变电磁方法探测地下水的赋存特征是其中的一项重点研究内容。以陕北煤矿区直罗组和延安组2个目标含水地层的地下水资源为研究对象，基于钻孔地质剖面和视电阻率测井曲线，构建了研究区主采煤层上覆地层的正常和异常地电模型。通过地面瞬变电磁一维正演模拟，获得了不同地电模型条件下的感应电压和全程视电阻率曲线，分析了各模型对应的瞬变电磁场响应数据之间的差异性，其结果表明目标含水层在不同富水条件下具有不同的瞬变电磁场响应特征，0.000 1～0.010 0 s是瞬变电磁场对不同目标含水层进行分辨的有效观测时间，从理论上确定了利用瞬变电磁法进行目标含水层富水性探测的可行性。现场探测试验进一步给出了适用于研究区的瞬变电磁观测参数，获得了目标含水层的电性参数分布特征，基于统计学原理确定直罗组和延安组含水层的电性异常判别阈值分别为34 Ω·m和48 Ω·m。以此为依据，揭示了直罗组和延安组地层的地下水赋存特征，总体上判定前者裂隙相对发育，具有较强富水性，后者岩层相对完整，具有弱富水性。最后，针对煤炭开采对地下水环境的影响规律研究，指出了后续瞬变电磁探测工作重点以及相关影响因素。

Large-scale exploitation of coal resources in the upper and middle reaches of the Yellow River basin has caused continuous deterioration of ecological environment. It is helpful to realize the coordinated development of coal resources exploitation and ecological environment protection to master the influence law of coal exploitation on groundwater environment. Using the transient electromagnetic method to study groundwater occurrence characteristics is one of the key contents. Take groundwater resources occurs in Zhiluo

Group and Yanan Group strata at Northern Shaanxi Coal Mining Area as two research objects,based on the drilling geological columnar and apparent resistivity logging curves,the normal and abnormal geoelectric models were constructed by the strata overlying the main coal seams in the study area. Through forward-modeling of the ground transient electromagnetic one-dimensional program,the induced voltage and all-time apparent resistivity curves were obtained by different geoelectric models,and the differences of data of transient electromagnetic field responded by different geoelectric models were analyzed. The results show that,the response characteristics of transient electromagnetic field changes with the water-rich conditions of the target aquifers and the effective observation time for the transient electromagnetic field to distinguish different target aquifers is 0.000 1 s to 0.01 s. The feasibility to detect the water content of the target aquifers using the transient electro

〖LM〗magnetic method can be determined in theory. The field detection test further gives the transient electromagnetic observation parameters applicable to the study area,and obtains the distribution characteristics of the electrical parameters of the target aquifer. Based on the principle of statistics,the identification threshold of the electrical anomaly of zhiluo and Yanan aquifers is determined to be 34 Ω·m and 48 Ω·m,respectively.According to this,the groundwater occurrence characteristics of zhiluo and Yanan strata are revealed respectively. In which,the former has strong water enrichment with relatively developed fissures of rock,and the latter has weak water enrichment with relatively integrality of rock. Finally,in view of the influence law of coal mining on groundwater environment,the subsequent focus of transient electromagnetic detection and related influencing factors are pointed out.