Influence And Correction Of Non-Geological Factors On Multi-Turn Small Loop Transient Electromagnetic Apparent Resistivity

In recent years,multi-turn small coil transient electromagnetic has developed rapidly and achieved good results in the detection of hidden water-rich area in the mine.However,the multi-turn small coil transient electromagnetic detection is affected by many factors,which affect the accuracy of transient electromagnetic detection and cause transient electromagnetic misdetection and missing detection.It is of great significance to study the influence factors of multi-turn small coil transient electromagnetic and to calibrate the transient electromagnetic according to the characteristics of the influence laws,so as to improve the accuracy of transient electromagnetic detection.The influence factors of transient electromagnetic are summarized and categorized,among which the influence of ferromagnetic materials is fully studied.This paper mainly studies the influence of spatial characteristics and the influence of device.According to the similarity criterion,the full space model of the roadway is established by using the water tank,and the comparison test is designed by using the control variable method.The influence factors such as the full space,the roadway,the coupling relationship between coil and roadway,the position of the measuring point,the different positions of the roadway relative to the abnormal body are studied respectively,and the influence characteristics of each factor on transient electromagnetic are analyzed.Repeated experimentation is used to control data quality,prevent accidental results,and ensure experimental repeatability.In the half-space environment on the ground,the influence of multi-turn small coil device is studied by using the actual coil size.By using control variable method,the influence of the device form,transmitting coil turns,transmitting coil side length are studied respectively.The experimental results show that the influencing factors have different effects on the transient electromagnetic apparent resistivity,and the side length of the transmitting coil has the greatest influence on the transient electromagnetic apparent resistivity.At the end of the paper,based on the similarity between shallow magnetic anomaly interference in geophysical magnetic exploration and transient electromagnetic random interference,the interpolation cutting method is implemented based on the principle of interpolation cutting method,and the denoising effect is compared.It is proved that the interpolation cutting algorithm can remove the transient electromagnetic random interference effectively on the premise of preserving the useful abnormal signals.