Three-dimensional forward modeling for surface-borehole transient electromagnetic method
Li Jianhui1,2, Liu Shucai3, Jiao Xianfeng3, Jiang Zhihai3, Hu Xiangyun1
1. Institute of Geophysics and Geometics, China University of Geoscience (Wuhan), Wuhan, Hubei 430074, China;
2. State Key Laboratory for GeoMechanics and Deep Underground Engineering, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China;
3. School of Resource & Geoscience, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China
Abstract：The surface-borehole configuration is one of the most useful working devices for transient electromagnetic method. However, forward modeling study for this method is not very popular. In this paper, we propose one-dimensional and three-dimensional forward modeling for surface-borehole transient electromagnetic based on 1D analytical method and vector finite element method. Comparing with one-dimensional analytical solution for layered medium and the numerical solution of vector finite element method for low resistivity sheet in homogeneous half-space, the validity of the three-dimensional algorithm is proved. In addition, we analyze the diffusion characteristics of transient electromagnetic field variation with time and depth using three-dimensional numerical simulation for low brick body of low resistivity.
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