Research on forward simulation of down-hole TEM based on the abnormal field
XU Zheng-Yu1,2, YANG Hai-Yan1,2, DENG Ju-Zhi2, TANG Hong-Zhi3, ZHANG Hua2, LIU Xu-Hua2, ZHAO Hai-Jiao2, GONG Jian-Jun2
1. Fundamental Science on Radioactive Geology and Exploration Technology Laboratory, East China Institute of Technology, Nanchang 330013, China;
2. School of Nuclear Engineering and Geophysics, East China Institute of Technology, Nanchang 330013, China;
3. Survey and Design Institute, East China Institute of Technology, Fuzhou 344000, China
In the down-hole TEM forward simulation, previous researchers usually studied total electric field and analyzed response characteristics. In this paper, the authors studied the abnormal field with the down-hole TEM, and simulated the response of single conduction plate and multiple conduction plates. Meanwhile, the down-hole TEM responses of a three-dimensional conductive plate in a typical half space model were simulated to obtain a "fixed source survey at different drill holes" and "fixed drill hole survey at different source places". First, the authors conducted derivation of difference equation of secondary field and made numerical calculation by using the finite difference method. Comparative studies indicate that during the study of the abnormal field in the down-hole TEM, the abnormal field can reflect the position of anomalous space parameters. The results show that the abnormal response of down-hole TEM becomes weaker with time delay, but the abnormal response characteristics remain unchanged in different drill holes, and the abnormal response difference in different source directions is obvious. The measurement results can be used to judge abnormal body space location information. Finally, the main factors that affect the down-hole TEM abnormal response are the depth of the target body, the coupling relationship between the target body and the drill hole and the source position. The research results provide a theoretical basis for interpretation guidelines for related data.
徐正玉, 杨海燕, 邓居智, 汤洪志, 张华, 刘旭华, 赵海娇, 巩建军. 基于异常场的地-井瞬变电磁法正演研究[J]. 物探与化探, 2015, 39(6): 1176-1182.
XU Zheng-Yu, YANG Hai-Yan, DENG Ju-Zhi, TANG Hong-Zhi, ZHANG Hua, LIU Xu-Hua, ZHAO Hai-Jiao, GONG Jian-Jun. Research on forward simulation of down-hole TEM based on the abnormal field. Geophysical and Geochemical Exploration, 2015, 39(6): 1176-1182.
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