1. School of Geophysics and Measurement-control Technology, East China University of Technology, Nanchang, Jiangxi 330013, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha, Hunan 410083, China
Abstract：We use the unstructured adaptive grid algorithm based on model sensitivity information to generate high-quality inversion-oriented meshes,and adopt them to 3D DC resistivity inversion.The model sensitivity is a measure of the overall response of underground model change to real datasets.So,the optimized mesh generated based on the model sensitivity information has higher quality than the ordinary mesh.This new mesh can reduce the dependence of inversion on model regularization constraints and improve the quality of inversion results.We use the minimum-structure inversion object function based on a tetrahedral element mesh.The Gauss-Newton method optimizes the inversion object function.The Gauss-Newton equation is solved by the stable double conjugate gradient method in order to increase the stability of 3D DC resistivity inversion.The calculating results of both synthetic and field data prove the validity of the proposed approach.
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