Geophysics and Geophysical Exploration (지구물리와물리탐사)

Korean Society of Earth and Exploration Geophysicists (한국지구물리·물리탐사학회)
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Three-dimensional Electromagnetic Modeling in Frequency Domain

주파수영역 전자법의 3차원 모델링

  • Jang, Hannuree (Green Energy Research Institute, Sejong University, Energy Resources Institute, Pukyong National University) ;
  • Kim, Hee Joon (Department of Energy Resources Engineering, Pukyong National University)
  • 장한누리 (세종대학교 그린에너지연구소, 부경대학교 에너지자원연구소) ;
  • 김희준 (부경대학교 에너지자원공학과)
  • Received : 2013.05.10
  • Accepted : 2014.07.08
  • Published : 2014.08.31

Abstract

Development of a modeling technique for accurately interpreting electromagnetic (EM) data is increasingly required. We introduce finite difference (FD) and finite-element (FE) methods for three-dimensional (3D) frequency-domain EM modeling. In the controlled-source EM methods, formulating the governing equations into a secondary electric field enables us to avoid a singularity problem at the source point. The secondary electric field is discretized using the FD or FE methods for the model region. We represent iterative and direct methods to solve the system of equations resulting from the FD or FE schemes. By applying the static divergence correction in the iterative method, the rate of convergence is dramatically improved, and it is particularly useful to compute a model including surface topography in the FD method. Finally, as an example of an airborne EM survey, we present 3D modeling using the FD method.

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Acknowledgement

Supported by : 한국연구재단, 한국에너지기술평가원(KETEP)

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