Abstract：In order to solve the problem that the detection blind area and the detection depth of the transient electromagnetic method to detect the underground,according to the working principle of the transient electromagnetic method,the technology of reduce the detection blind area depth and increase the detection depth of transient electromagnetic method is studied. According to the principle of least square method,it is used the Matlab to fit the induction potential decay curves on the basis of the early signal,then dealing with the software of YCS40( A) to stack,it can get the ideal results after forth fitting that can effectively reduce the blind area depth to 18 m. Compared and analyzed the coil size,emission frequency and depth coefficient of transient electromagnetic instrument,it found that using the 2 m transmitter coil with high current,adjusting the minimumtransmission frequency and increaseing deep conversion coefficient can increase the TEM detection depth. The results can guide the application of the transient electromagnetic method,and has the significance to ensure safe production of coal mining enterprises.

Keyword：transient electromagnetic method;blind area;detection depth;extraction radius;