Occam inversion of CSAMT data in layered media with azimuthal anisotropy
CAO Qiang1,2,3, LIN Chang-Hong1,3, TAN Han-Dong1,3, GONG Ying-Li1,3
1. Key Laboratory of Geo-detection (China University of Geosciences), Ministry of Education, Beijing 100083, China;
2. China Railway ErYuan Engineering Group CO.LTD, Chengdu 610031, China;
3. School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China
At present, the inversion of controlled source audio-frequency magnetotelluric data is mainly based on the isotropic media. Because of the rock fracture or the shape of mineral, the resistivity is different in each direction in the complicated geoelectric body. To fit actual geological conditions better, this paper mainly probes into the inversion of controlled source audio-frequency magnetotelluric data in layered media with azimuthal anisotropy induced by ground orthogonal horizontal electric dipoles. We develop an Occam inversion algorithm to invert controlled source audio-frequency magnetotelluric data for azimuthal anisotropy in layered media. Designing the theoretical geoeletric models, the synthetic examples demonstrate the validity and stability of the Occam inversion algorithm. At the same time, the inversion results of different data suggest that in order to get better inversion results of azimuthally anisotropic layered media the apparent resistivities ρsxy,ρsyx, and phases φxy,φyx, should be used.
曹强, 林昌洪, 谭捍东, 龚应丽. 可控源音频大地电磁法方位非各向同性层状介质Occam反演[J]. 物探与化探, 2016, 40(3): 594-602.
CAO Qiang, LIN Chang-Hong, TAN Han-Dong, GONG Ying-Li. Occam inversion of CSAMT data in layered media with azimuthal anisotropy. Geophysical and Geochemical Exploration, 2016, 40(3): 594-602.
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