3D DC Resistivity Inversion with Topography Based on Regularized Conjugate Gradient Method

During the past decades, we observed a strong interest in 3D DC resistivity inversion and imaging with complex topography. In this paper, we implemented 3D DC resistivity inversion based on regularized conjugate gradient method with FEM. The Fréchet derivative is assembled with the electric potentia...

Full description

Bibliographic Details
Main Authors: Jian-ke Qiang, Xue Han, Shi-kun Dai
Format: Article
Language:English
Published: Hindawi Limited 2013-01-01
Series:International Journal of Geophysics
Online Access:http://dx.doi.org/10.1155/2013/931876
Description
Summary:During the past decades, we observed a strong interest in 3D DC resistivity inversion and imaging with complex topography. In this paper, we implemented 3D DC resistivity inversion based on regularized conjugate gradient method with FEM. The Fréchet derivative is assembled with the electric potential in order to speed up the inversion process based on the reciprocity theorem. In this study, we also analyzed the sensitivity of the electric potential on the earth’s surface to the conductivity in each cell underground and introduced an optimized weighting function to produce new sensitivity matrix. The synthetic model study shows that this optimized weighting function is helpful to improve the resolution of deep anomaly. By incorporating topography into inversion, the artificial anomaly which is actually caused by topography can be eliminated. As a result, this algorithm potentially can be applied to process the DC resistivity data collected in mountain area. Our synthetic model study also shows that the convergence and computation speed are very stable and fast.
ISSN:1687-885X
1687-8868