CHEN Han-Bo,
LI Tong-Lin,
XIONG Bin et al
.2017.Finite-element modeling of 3D MCSEM in arbitrarily anisotropic medium using potentials on unstructured grids.Chinese Journal Of Geophysics,60(8): 3254-3263,doi: 10.6038/cjg20170830
Finite-element modeling of 3D MCSEM in arbitrarily anisotropic medium using potentials on unstructured grids
CHEN Han-Bo1, LI Tong-Lin1, XIONG Bin2, CHEN Shuai1, LIU Yong-Liang1
1. College of Geo-Exploration Sciences and Technology, Jilin University, Changchun 130026, China; 2. College of Earth Sciences, Guilin University, Guangxi Guilin 541004, China
Abstract：A secondary potential formulation of the three-dimensional marine controlled source electromagnetic method modeling in arbitrarily anisotropic medium is derived based on unstructured grids and coulomb gauge. Next, solving the finite element equations with IDR(s) iterative algorithm combined with the incomplete LU decomposition technology. Once the secondary vector and scalar potential is solved, we can use the moving least square method to calculate their spatial derivative and compute the secondary electric and magnetic field. In order to test the finite element method for numerical modeling of 3D controlled sources electromagnetic data in an arbitrarily anisotropic conductive medium of this paper, we have applied the developed algorithm to compute the typical CSEM response of two 3D models. The modeling results show that the proposed algorithm is feasible and effective; the IDR(s) is competitive with or superior to ILU-QMR and ILU-BICGSTAB methods; the proposed algorithm is general and can be applied to EM modeling in borehole and environment geophysics in arbitrarily anisotropic medium.
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