Based on the data obtained from the 1∶5 000 helicopter electromagnetic and magnetic comprehensive survey in 2004,in combination with ground coal geology as well as geophysical prospecting and remote sensing information,the authors studied the relationship between the aeroelectromagnetic or aeromagnetic characteristics and the distribution of underground coal fire in Wuda area,Inner Mongolia.

This paper introduces the working principles of high density resistivity method and the field work method,probes into some problems that should pay attention to in detecting the multi-layer goaf by using the high density resistivity method,and expounds the concrete steps of detecting the multi-layer goaf of underground coal seam.