Intelligent identification of gas anomalous area by electro-magnetic joint exploration technology

For intelligent and accurate identification of the gas anomalous area, two geophysical exploration methods, namely, the direct current (DC) method and the transient electromagnetic method, were adopted for advance detection of the underground roadway before the joint inversion of the detection data to obtain the fusion image of apparent resistivity. Based on the high-resistivity area in the image, the range of 13–65 m ahead of the driving face is the gas anomalous area. According to the test results of gas prediction indexes q and Δh 2, there is an area with high prediction values in front of the roadway, which is consistent with that determined by geophysical exploration. From the analysis of the thickness of exposed coal, there is an area with large coal thickness ahead of the roadway where there is an increase in gas content. The electrical characteristics of the coal are changed in the area, contributing to the anomalous resistivity, which keeps in consistency with the results of geophysical exploration. Therefore, the electro-magnetic joint exploration technology can realize the intelligent identification of gas anomalous areas, which is of great significance for the efficient and accurate detection of gas anomalous area in the coal seam.