煤层气水力压裂技术是提高煤矿井下煤层气资源采出率的有效方法，但对于水力压裂效果的检测评价一直缺乏较为理想的方法，传统通过监测钻孔测量水压或介质含水性的办法成本高、效率低、不直观，为解决高效形象地检测水力压裂效果这一问题，提出一种煤矿井下在压裂孔内施工的动源动接收瞬变电磁探测方法。该方法使用由固定相对位置的极小发射线圈和接收探头组成的收发装置，在孔内沿钻孔逐点移动进行三分量观测，进而实现对钻孔径向微小低阻地质异常体的高精度探测。该方法对收发装置参数变化敏感，通过大量的物理模拟试验分析了单支曲线特征和多测道的异常响应特性，选定了最优的收发系统、发射线圈匝数、线径、发射电流强度、接收线圈匝数、线径和磁芯长度等参数，形成了最理想的单孔瞬变电磁探测装置;对比了该方法垂直分量观测曲线与常规矿井瞬变电磁探测曲线的形态，给出了垂直分量数据的预处理技术和数据处理方法;提出了水平分量数据的探头姿态变化影响的校正方法，采用趋势面提取技术完成了水平分量数据纯异常场的提取，通过异常场形态组合和幅值关系实现了异常体中心方位角定位;考虑压裂裂缝的特殊性，研发了利用Suffer和Voxler软件功能的充水裂缝三维立体成像技术。井下现场物理模拟试验对比了巷-孔瞬变电磁与单孔瞬变电磁的径向探测距离，验证单孔方法径向探测能力约为巷-孔方法的1/2。结合韩城煤矿井下的工程实践，对该方法精细检测煤层气水力压裂形成裂缝的性质、形态和规模的实用性和有效性进行了检验。研究表明:单孔动源动接收瞬变电磁探测方法是井下物探、钻探和煤层气压裂技术的有机结合与相互补充，能够有效应用于压裂效果的检测和评价。

Coalbed methane hydraulic fracturing technology is an effective way for enhancing the output ratio of underground coal mine coalbed methane resources,but there has been a lack of ideal method to test and assess the effectiveness of hydraulic fracturing. The traditional way of monitoring and measuring hydraulic pressure or medium aquosity is high cost,low efficiency and not intuitive. In order to solve the problem in assessing the effectiveness of hydraulic fracturing efficiently and visually,a dynamic source and reception TEM detection method was proposed to apply in underground coal mine fracturing borehole. This method uses the R-T unit,composed of the position relatively fixed minimal transmitting coil and receiving probe,to conduct three-component measurement along the bore-hole point by point,and then realize a high-precision detection for the tiny geological anomalous bodies around borehole’s radial direction. This method is sensitive to the parameter of the R-T unit,thus numerous physical modelling experiments were designed to analyze the characteristics of single curve and multichannel abnormal responses. After that,the most suitable R-T unit parameters was selected,such as the number of turns of transmit coil and its wire diameter,transmit current magnitude,the number of turns of receive coil and its wire diameter,the length of magnet core and so on,then formed the ideal single-hole TEM unit. Compared the vertical component observation curve of single-hole TEM with traditional coal mine TEM curve,a data preprocessing and processing method for vertical component data was proposed. A rectification method for horizontal component data caused by probe attitude was proposed,using trend-surface extract technology realized pure anomalous field extraction of horizontal component data. The abnormal body’s center azimuth was located by analyzing the relation of abnormal body space form combination and its amplitude. Considering the particularity of fracturing cracks,a 3D imaging technology,adopting the function of Suffer and Voxler software,was developed. The results from the comparison on the radius of radial investigation of roadway-borehole TEM with single borehole TEM in underground field experimentation verified that the radial detection capacity of single borehole TEM was half of the roadway-borehole TEM. Combined with engineering practice in Hancheng Mining Industry Corporation,the method’ spracticability and availability for fine detecting the cracks’characteristic,form and scale,which were formed by coalbed methane hydraulic fracturing,were tested. The research shows that the single-hole dynamic source and reception TEM detection method is an effective combination and mutual complementation of underground geophysical exploration technology,drilling technology and coalbed methane hydraulic fracturing technology,can meet the requirements of testing and evaluating the effectiveness of hydraulic fracturing.