Water inrush disasters poses a great threat to the safe exploitation of coal resources. To solve this problem, the transient electromagnetic method (TEM) was proposed to accurately detect the water accumulation in the goaf. The electromagnetic response characteristics of different water-filled goaves were studied by electromagnetic field theory, numerical simulation and field verification. Through the models of 100% water accumulation, 50% water accumulation, 0% water accumulation, 100% water accumulation with collapsed rock, 50% water accumulation with collapsed rock and 0% water accumulation with collapsed rock goaf, the characteristics of induced voltage attenuation curves were studied. Meanwhile, the relationship between the attenuation voltage value and area of the transmitting coil, the depth of the goaf, the background resistivity, and the delay time were also simulated. The results illustrate that the attenuation curve of induced voltage presented a regular exponential decay form in the 0% water accumulation model but existed abnormal exaltation for voltage in water-filled model. Through the linear fitting curve, it can be seen that the abnormal intensity of the induced voltage becomes stronger as the distance between the measuring point and the center of the target decrement. Moreover, the abnormal amplitude of the induced voltage increases with the rise of the water accumulation and collapsed rock will weakly reduce the low-resistivity anomalous effect on the water-accumulated goaf. In addition, the response value of the attenuation voltage increased as the area of the transmitting coil increases, but decreased with increasing delay time and increasing background resistivity and depth of the target body. The field detection results of the Majiliang coal mine also confirmed the theoretical analysis and the numerical simulation.

突水灾害对煤炭资源的安全开采构成了巨大威胁。为了解决这个问题，提出了瞬态电磁法（TEM）来准确检测采空区的积水。通过电磁场理论、数值模拟和现场验证研究了不同充水采空区的电磁响应特性。通过100%积水、50%积水、0%积水、100%塌岩积水、50%塌岩积水和0%塌岩采空区积水模型，得出感应电压衰减特性曲线进行了研究。同时，衰减电压值与发射线圈面积、采空区深度、背景电阻率、并模拟了延迟时间。结果表明，在0%蓄水模型中，感应电压的衰减曲线呈现规律的指数衰减形式，而在充水模型中则存在电压异常升高的现象。通过线性拟合曲线可以看出，随着测量点到目标中心距离的减小，感应电压的异常强度越来越强。此外，感应电压的异常幅值随着积水的增加而增大，崩塌的岩石会弱弱地降低对积水采空区的低电阻率异常效应。此外，衰减电压的响应值随着发射线圈面积的增加而增加，但随着延迟时间的增加和目标体的背景电阻率和深度的增加而降低。马鸡梁煤矿的现场检测结果也证实了理论分析和数值模拟。