Inversion method of transient electromagnetic virtual wave-field applied to advance detection in underground mine

In order to solve a low accuracy problems to explain the abnormal body size and location advance detected by the mine transient electromagnetic, a tota | waveform inversion method was applied to the velocity analysis on the data of the virtual wave-field obtained with the wave-field contra-variant and the inversion imagi ng method of the transient electromagnetic virtual wave-field was provided. According to the hidden water disaster in the front of the heading face, a 3D numerical mod el, physical simulation and engineering cases were applied to the practical and effective verification of the method. The study results showed that the method could not only well reflect the two layer electrical interfaces of the water bearing fault model with abnormal amplitude over 30% and could have same accurate effect of the water flooded roadway model with the abnormal amplitude less than 5%. In addition, the method could reduce the shallow depth blind area to 0 by the advance detection of th e mine transient electromagnetic and could accurately position the actual location of the low resistance abnormal body.