The principles, methods, technologies and application effects of several elec-tromagnetic methods for the detection of the hidden danger of water gushing at the coal face were introduced. Also, emphasis was laid on expounding the methods, principles and effects of down-hole detections by electric transmission tomography and transient elec-tromagnetic method. The potential of point power supplied in the underground homoge-neous semi-space, as well as the response to a low-resistivity abnormal body in the ho-mogeneous semi-space, was simulated by adopting 3-D finite element method to interpret the basic theory of the electric transmission tomography. The results of actual measure-ment show that the mine electromagnetic method is sensitive to water-bearing low-resistivity bodies and can play a unique role in detecting the hidden danger of water gushing at the coal face.
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