Abstract
We propose a 3-D transient electromagnetic inversion method based on explicit finite-difference forward modeling. For forward modeling, we calculate the whole-space initial field excited by magnetic dipole sources at an initial time after the current is switched off and apply Maxwell’s equations on time using the modified DuFort–Frankel method and staggered grids. For inversion, we use the least squares optimization method. We test the inversion method using synthetic and field data. The conductivity brick is recovered well in synthetic. The inversion results of field data are consistent with the known geological conditions. The synthetic and field examples show that the inversion method based on explicit finite-difference forward modeling is effective.
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Acknowledgments
This work is supported by the Natural Science Foundation of China (Grant no. 41974088) and Natural Science Foundation of Hebei Province of China (Grant No. D2023508001). We would like to thank the reviewers and editors for their thoughtful and constructive comments on this paper.
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Li Fei, an associate professor, graduated from China University of Mining and Technology, Beijing, with a PhD in applied geophysics. He is currently working at the North China Institute of Science and Technology. His research focuses on geophysical prospecting technology of mine disasters and geophysical forward and inversion.
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Li, F., Tan, Q., Wen, LF. et al. 3-D transient electromagnetic inversion based on explicit finite-difference forward modeling. Appl. Geophys. 20, 310–315 (2023). https://doi.org/10.1007/s11770-023-1028-9
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DOI: https://doi.org/10.1007/s11770-023-1028-9