Physical Simulation And Application Of Multi-component Transient Electromagnetic Method In Heading Faces Of Water-rich Area

Mine water inrush often happened in Heading Face. Mine transient electromagnetic method is one of the most effective methods to perform the advanced detection of heading face.In the past, the theoretical research of mine transient electromagnetic detection had been focused on the vertical component instead of the horizontal component.However, the horizontal component response contains large number of abnormal body information.Comprehensive analysis to the horizontal and vertical component can help to determine the underground anomaly more accurately, which will greatly improve the accuracy of transient electromagnetic data interpretation.In order to grasp the law of multi-component response of transient electromagnetic method, in this paper, the relative position of the receiving coil will be changed by exciting a single transmitting coil to achieve the purpose of receiving the transient electromagnetic multi-component. At the same time, the advanced detectiongeological-geophysical model of mine transient electromagnetic will be established based on the typical characteristics of the mine heading face in water rich area and the similarity criterion of the physical simulation.Physical simulation will be carried out in typical water rich area of the coal mine.And there are application examples to illustrate the conclusions.Research results show that :due to the common central point of the transmit coil and the receiving coil,the response intensity and detecting distance of Z component is the largest one, X component is the second, Y component is the smallest;When the goaf water and the water containing(conductive) collapse column are located in front or left/right front of the tunnel, the Z component presents anomalies with peak, and the curve of the potential profile is symmetrical about the center point, which can reflect the center of the abnormal body; X component presents anomalies with passing center point of the abnormal body, and the maximum and minimum values are located at the boundary of the abnormal body. When water containing(conductive) fault is located in front of the tunnel, the Z component presents anomalies with peak, the maximum is located at the center of the fault, X component presents anomalies with passing center point of the abnormal body, and the zero crossing position of X component can not only respond to the center of the anomaly body, but also respond the fault tendency.Through practical application, the exploration results basically accord with the results of physical simulation. It shows thatmulti-component of mine transient electromagnetic method can greatly improve the interpretation accuracy.