Abstract
In this paper, we extend the scope of numerical simulations of marine controlled-source electromagnetic (CSEM) fields in a particular case of anisotropy (dipping anisotropy) to the general case of anisotropy by using an adaptive finite element approach. In comparison to a dipping anisotropy case, the first order spatial derivatives of the strike-parallel components arise in the partial differential equations for generally anisotropic media, which cause a non-symmetric linear system of equations for finite element modeling. The adaptive finite element method is employed to obtain numerical solutions on a sequence of refined unstructured triangular meshes, which allows for arbitrary model geometries including bathymetry and dipping layers. Numerical results of a 2D anisotropic model show both anisotropy strike and dipping angles have great influence on the marine CSEM responses.
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Li, Y., Luo, M. & Pei, J. Adaptive finite element modeling of marine controlled-source electromagnetic fields in two-dimensional general anisotropic media. J. Ocean Univ. China 12, 1–5 (2013). https://doi.org/10.1007/s11802-013-2110-3
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DOI: https://doi.org/10.1007/s11802-013-2110-3