Detection of Abandoned Mines and Burning Centers of Mine Fires by Combined Electromagnetic Method

The high resolution earth resistivity method (HRRM) is developed specifically for detecting abandoned underground cavities. HRRM has a special feature in that it can recognize and cancel static shift,which makes it defferent from the high density resistivity method(HDRM). In searching for various means for detecting underground cavities,we found that the detecting depth of the transient electromagnetic method(TEM) depends mainly on the measurement duration,not the loop area. In addition,TEM can also be used to locate the high-resistivity bodies. In order to use them for local working site conditions,we combine HRRM with TEM to become a combined electromagnetic method.Since the late 1980´s this method has been used to locate abandoned mines and burning centers of mine fires with great success.This paper cites case studies for which this technique was successfully used.