瞬变电磁法在探测导水通道方面具有良好的效果，但是常规的方法探测导水裂隙带发育会受到环境的影响，不适宜完成探测工作。为此，采用孔中瞬变电磁法，对井下覆岩导水裂隙带发育高度进行研究，利用COMSOL软件对于孔中瞬变电磁法的传播特性和响应特征进行研究，并结合孔中瞬变电磁探测试验，研究孔中瞬变电磁探测导水裂隙带的可行性。研究结果表明：孔中瞬变电磁可以有效完成异常体的探测任务，通过调整收发装置的位置以达到提高信噪比的效果，孔中瞬变电磁径向扩散方式与矿井瞬变电磁理论基本相同；但是，模拟发现低阻区响应场受高阻区影响较大，导致60 m交界面相邻低阻区衰减速度过快，响应曲线在低阻区出现“尖点”，说明受高阻岩体影响60 m附近的低阻区视电阻率大于低阻区理论值。经过井下试验得出：孔中瞬变电磁探测已开采煤层导水裂隙带发育异常明显，且成片连接；而未开采煤层瞬变电磁低阻异常不明显，且未形成大片连接，说明通过钻孔瞬变电磁系统观测导水裂隙带高度具有较高的可行性。

Transient electromagnetic method has shown great effectiveness in detecting water channels. However, conventional methods for detecting the development of water-conducting fracture zones are not suitable due to environmental influences. In this study, the borehole transient electromagnetic method was used to investigate the development height of water-conducting fracture zones in the overlying strata underground. The propagation characteristics and response features of the borehole transient electromagnetic method were studied using COMSOL software. Combined with borehole transient electromagnetic testing, the feasibility of detecting water-conducting fracture zones using the borehole transient electromagnetic method was investigated. The research results showed that the borehole transient electromagnetic method can effectively complete the task of detecting anomalous bodies. The signal-to-noise ratio can be improved by adjusting the position of the transmitter-receiver devices. The radial diffusion mode of the borehole transient electromagnetic method is basically the same as the theory of mine transient electromagnetic. However, simulations revealed that the response field of low-resistivity zones is greatly affected by high-resistivity zones, resulting in rapid attenuation of adjacent low-resistivity zones near the 60 m interface and the appearance of “peak points” in the response curve of the low-resistivity zones. This indicates that the apparent resistivity of the low-resistivity zones near the 60 m interface is greater than the theoretical value of the low-resistivity zones due to the influence of high-resistivity rock masses. Through underground experiments, it was concluded that the borehole transient electromagnetic method can effectively detect the significant abnormal development of water-conducting fracture zones in mined coal seams, which are connected in large patches. In contrast, the low-resistivity anomalies in unmined coal seams using the transient electromagnetic method are not obvious, and large-scale connections have not been formed. This suggests that observing the development of water-conducting fracture zones through the borehole transient electromagnetic system is highly feasible.