The influence of magnetic susceptibility on MT response and its extraction method
WANG Jun-Lu1, WANG Meng2, LI Dang1, LI Jian-Hua1, LIN Pin-Rong1
1. Institute of Geophysical and Geochemical Exploration, CAGS, Langfang 065000, China;
2. China Aero Geophysical Survey and Remote Sensing Center for Land and Resources, Beijing 100083, China
In electromagnetic theory,conductivity and permeability are two important petrophysical parameters.The electromagnetic signal will inevitably be affected by the magnetic properties of the media in MT detection where magnetism is strong.The authors made the numerical simulation of the electromagnetic finite element method with magnetic susceptibility by introducing the magnetic susceptibility parameter into the two-dimensional MT forward theory.Prism model was established for calculation and analysis of the influence of the magnetic susceptibility parameters on the electric field,magnetic field,MT apparent resistivity and phase parameters.The numerical simulation results show that the high magnetic medium results in increasing the electric field,reducing the magnetic field,increasing the apparent resistivity,and complex changes of phase and,with the increase of the magnetic substance or the increase of the magnetization rate,the effect gradually becomes larger.The inversion results of geoelectric model with high magnetic middle layer are good.The results obtained by the authors provide a theoretical basis for the MT work in the high magnetic area and also have a certain significance for conducting the mineral prospecting in "the second space".
王珺璐, 王萌, 李荡, 李建华, 林品荣. 磁化率对大地电磁响应的影响及其提取方法[J]. 物探与化探, 2015, 39(6): 1292-1298.
WANG Jun-Lu, WANG Meng, LI Dang, LI Jian-Hua, LIN Pin-Rong. The influence of magnetic susceptibility on MT response and its extraction method. Geophysical and Geochemical Exploration, 2015, 39(6): 1292-1298.
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