Study on Physical Simulation Experiment of Borehole Transient Electromagnetic Method for Advance Detection
The borehole transient electromagnetic method uses a small transceiver coil to send pulses to the primary field in the borehole to observe the secondary field intermittently,and to process and interpret the data,so as to achieve the purpose of detecting the abnormal water body around the borehole.Based on the basic theory of transient electromagnetic and the similarity criterion,a physical simulation test platform of water tank is built.Response characteristics of different axial and radial distance anomalous bodies of coaxial devices and coplanar devices,plate anomalous bodies of coaxial devices and radial multi-point detection anomalous bodies of coplanar device are analyzed by physical simulation test.The results show that the induced electromotive force increases when there is an abnormal body.The closer the abnormal body is,the stronger the induced electromotive force is and the more obvious the abnormal characteristics are.The induced electromotive force of the plate abnormal body increases in the early and middle stages,while the induced electromotive force of the columnar and massive abnormal body increases in the whole process.The smaller the inclination of the plate anomaly,the more obvious the induced electromotive force rise and the more obvious the anomaly characteristics.Apparent resistivity imaging results of radial multipoint detection in the drilling of a coplanar device show that the contour characteristics of the abnormal body are obvious,and the physical simulation results fully verify the effectiveness of the method.
万方数据
维普
