3D finite-difference modeling algorithm and anomaly features of ZTEM
Wang Tao1, Tan Han-Dong1, Li Zhi-Qiang1, Wang Kun-Peng1, Hu Zhi-Ming1, and Zhang Xing-Dong1
1. Key Laboratory of Geo-detection Ministry of Education and School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China.
Abstract The Z-Axis tipper electromagnetic (ZTEM) technique is based on a frequency-domain airborne electromagnetic system that measures the natural magnetic field. A survey area was divided into several blocks by using the Maxwell’s equations, and the magnetic components at the center of each edge of the grid cell are evaluated by applying the staggered-grid finite-difference method. The tipper and its divergence are derived to complete the 3D ZTEM forward modeling algorithm. A synthetic model is then used to compare the responses with those of 2D finite-element forward modeling to verify the accuracy of the algorithm. ZTEM offers high horizontal resolution to both simple and complex distributions of conductivity. This work is the theoretical foundation for the interpretation of ZTEM data and the study of 3D ZTEM inversion.
This work was supported by the Natural Science Foundation of China (No. 41374078) and Geological Survey Projects of Ministry of Land and Resources of China (No. 12120113086100 and 12120113101300).
Cite this article:
. 3D finite-difference modeling algorithm and anomaly features of ZTEM[J]. APPLIED GEOPHYSICS, 2016, 13(3): 553-560.
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2016, Vol. 13 
