矿井水力压裂技术在坚硬顶板卸压和瓦斯高效抽采领域得到的广泛应用，但对于长钻孔水力压裂效果的检测评价一直缺乏较为理想的物探方法，传统探测方法存在成本高、效率低与探测距离短的不足。为实现坚硬顶板定向长钻孔水力压裂效果高效直观地检测这一目标，采用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，探测装置天线是由收发间距固定的极小发射线圈和三分量接收探头组成，在钻孔内沿钻孔逐点移动进行三分量接收。为了弥补有缆装置探测距离的不足，采用孔外定时同步、孔内发射接收的探测装置，采用钻机推送的方式对神东某矿井2号压裂钻孔40～315 m段进行压裂前、压裂后分别探测。首先对垂直分量数据进行预处理，采用水平分量数据实现探头姿态变化影响校正，并提取纯异常场进行分析，最终实现充水裂缝三维成像技术。试验结果表明：纯异常场等值线图中有明显条带状低阻异常分布，综合分析压裂前、后视电阻率分布情况认为该条带状低阻异常即为压裂形成裂缝所致，异常走向即为裂缝延伸方向，异常延伸范围即为裂缝延伸范围。三分量瞬变电磁探测技术是矿井物探、钻探和水力压裂技术的有机结合与相互补充，对裂缝走向和延展范围进行有效圈定，能够有效应用于坚硬顶板定向长钻孔水力压裂效果评价。

Mine hydraulic fracturing technology has been widely used in the fields of hard roof pressure relief and high-efficiency gas drainage. However, there has been a lack of ideal geophysical prospecting methods for the detection and evaluation of hydraulic fracturing effects in long boreholes. Traditional detection methods have the shortcomings of high cost, low efficiency and short detection distance. In order to achieve the goal of efficient and intuitive detection of the hydraulic fracturing effect of long directional drilling in hard roofs, a dynamic source-dynamic receiving transient electromagnetic detection method was adopted for the construction of fracturing holes in coal mines. The antenna of the detection device is composed of a minimum transmitting coil with fixed transceiver spacing and a three-component receiving probe, which moves point by point in the borehole to perform three-component receiving. In order to make up for the lack of the detection distance of the cable device, a detection device with timing synchronization outside the hole and transmission and reception inside the hole was used to detect the 40-315 m section of the No. 2 fracturing borehole in a Shendong mine before and after fracturing. Firstly, the vertical component data was preprocessed, and the horizontal component data was used to correct the influence of probe attitude change, and the pure anomaly field is extracted for analysis. Finally, the three-dimensional imaging technology of water filling cracks was realized. The test results show that there are obvious strip-shaped low-resistivity anomalies in the contour map of the pure anomaly field. By comprehensively analyzing the distribution of apparent resistivity before and after fracturing, it is considered that the strip-like low-resistivity anomalies are caused by fractures formation, and the abnormal strike is the fracture extension direction, and the abnormal extension range is the fracture extension range. The three-component transient electromagnetic detection technology is an organic combination and complementation of mine geophysical exploration, drilling and hydraulic fracturing technology. It can effectively delineate the fracture trend and extension range, and can be effectively applied to the evaluation of hydraulic fracturing effect of directional long borehole with hard roof plate.