A new way to extract the abnormal response of complex resistivity based on GEMTIP model

Spectrum induced polarization method is mainly used for geological survey according to the difference of conductivity and polarization of medium. Combined with the needs of national strategic development, this paper studies the three-dimensional finite element numerical simulation method of complex resistivity based on generalized equivalent dielectric induced polarization (GEMTIP) model. This method has been widely used in resource exploration, engineering geology and other fields. First, the GEMTIP model and the complex resistivity variation characteristics of GEMTIP model under the influence of different parameters was introduced. Then, the variation equations were established for two-point sources of 3D modeling of complex resistivity method. The computing area was divided into hexahedral elements. The complex potential and the complex conductivity of rocks within each triangular lattice were described by a linear interpolation to create a linear equations system from the variation equation. The BICGSTAB (Bi-conjugate gradient stabilized method) algorithm with incomplete LU decomposition for preconditioning was used to solve the system linear equation to calculate the anomalous complex potential of all nodes and the apparent complex resistivity on the surface. Finally, this approach was verified through the calculations of a two layered model. Two typical geoelectric models were designed to test the correctness and efficiency of the algorithm. The results show that it provides new way to further study the induced polarization effect of rock and ore on the acroscopic scale.