TEM FORWARD AND INVERSION OF ARBITRARY SHAPE LOOP SOURCE IN LAYERED MEDIA
LI Jian-ping1, LI Tong-lin2, ZHANG Ya-dong3
1. School of Geological Science & Engineering, Shandong University of Science and Technology, Qingdao 266510, China;
2. School of GeoExploration Science and Technology, Jilin University, Changchun 130026, China;
3. Exploration Department of Changqing Oil Field, Xi'an 710000, China
Abstract:The EM field of arbitrary shape loop can be regarded as EM field with the summation of many horizontal electric dipoles; therefore, as long as we work out the horizontal electric dipoles of the EM field and add them up, we can get the EM field of the arbitrary shape loop. The key of this method is the division of electric dipoles in arbitrary shape loop. In this paper, according to distance from the measuring point to the line of loop, each line of loop is divided into many small pieces with each piece satisfying the condition of horizontal electric dipole, and then numerical integration of horizontal electric dipole is carried out. In this way, the EM field of the whole loop can be obtained. Tests show that this method can not only reduce calculation amount but also improve calculation precision.
李建平, 李桐林, 张亚东. 层状介质任意形状回线源瞬变电磁场正反演[J]. 物探与化探, 2012, 36(2): 256-259.
LI Jian-ping, LI Tong-lin, ZHANG Ya-dong. TEM FORWARD AND INVERSION OF ARBITRARY SHAPE LOOP SOURCE IN LAYERED MEDIA. Geophysical and Geochemical Exploration, 2012, 36(2): 256-259.
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