Experimental study on transient electromagnetic method with a conical source

A new transmitter device-conical source has been proved theoretically to have several advantages for transient electromagnetic sounding. To verify application ability of conical source, two kinds of transmitter devices were designed and made, and the experimental studies on surface and in mine roadway were carried out. By applying high density resistivity achievements in surface experiment, the detecting results using conical source and multi-coils were compared. The results show that the description of strata resistivity with conical source is better than that with multi-coils. One fault was identified and the strike and position of which matches the high density resistivity result better. Meanwhile, experiment results in mine roadway also show that the conical source can achieve more effective delineation of low resistivity zone than multi-coils; the low resistivity zone in multi-coils section was turned out to be two discontinuous areas in conical source section. In addition, the conical source has a higher resolution of conductor in mine drift. The shape and area of conical source are more stable, which is more helpful to improve the efficiency and data quality of the transient electromagnetic method.