Two-Dimensional Magnetotelluric Forward Research for the Vertical Anisotropy

Miao-Xin Yang, Han-Dong Tan, Mao Wang, Huan Ma

School of Geophysics and Information Technology, China University of Geosciences, Beijing, China.

DOI: 10.4236/ijg.2015.610091                

Abstract

When we study and process magnetotelluric data, the earth's interior structure is usually equated with isotropic medium in the existing approaches. When the underground structure is complex, there is serious resistivity anisotropy in macroscopic view, and then the traditional processing and interpretation methods often produce wrong results. For that we must establish the study method based on the anisotropy in order to explain the measured data exactly. In this paper, by considering the change of resistivity in three electrical spindle directions, we deduce two-dimensional magnetotelluric variational equation for vertical anisotropy. The study region is divided into many rectangular units, and it is dealt with linear interpolation in each of them. By comparing with former achievements including the results of the isotropic and anisotropic models, it demonstrates the validity of the program. The pseudosection map of vertical anisotropic body shows that we can’t ignore the anisotropy effect and provides a solid foundation for the further inversion study.

Keywords

Vertical Anisotropy, Magnetotelluric Method, Isotropy, Anisotropy Effect

Conflicts of Interest

The authors declare no conflicts of interest.

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