Magnetotelluric forward study of the tilted electric anisotropic media
LIU Hong-Zhou, AN Ya-Ting
Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education, Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China
Abstract：The study of the electric anisotropy properties of strata can delineate oil and gas reservoirs in the strata and the deep linear structure related to geodynamic process and earthquake prediction. On the basis of magnetotelluric response formula in N-layer tilted electric anisotropic media obtained by the authors and under the condition of different electric anisotropy coefficients, dip angles of strata and thicknesses of tilted beds, the authors conducted forward calculation of the model for electric anisotropic tilted strata. The results show that, when any one of the three variables (electrical anisotropy coefficient, dip angle of strata, and depth of strata) is changed, the shape of the apparent resistivity curve remains basically unchanged, but the amplitude value of the apparent resistivity curve varies considerably, that the apparent resistivity curve is most sensitive to the change of the dip angle parameter of strata, and that the increase of the electric anisotropy coefficient can clearly demonstrate the resistivity anomaly of the thin layer. The results achieved by the authors will be helpful to electric anisotropic media magnetotelluric inversion and applied research in future.
刘鸿洲, 安亚婷. 倾斜电各向异性介质大地电磁正演研究[J]. 物探与化探, 2014, 38(6): 1241-1245.
LIU Hong-Zhou, AN Ya-Ting. Magnetotelluric forward study of the tilted electric anisotropic media. Geophysical and Geochemical Exploration, 2014, 38(6): 1241-1245.
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