Based on the Maxwell equations,the authors introduced the vector potential and scalar potential coupling equations,and used the finite element method to study the three-dimensional numerical simulation of WFEM.In a synthetic test,the correctness of this algorithm was verified by a uniform half-space model with analytical solutions.Then the detection depth of the WFEM was simulated using the anomalous bodies at two different depths.The numerical simulation results show that the WFEM don't affected by the near region of the field source and has the characteristics of large depth,it can provide theoretical and methodological support for deep earth resource exploration.
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