Geophysics and Geophysical Exploration (지구물리와물리탐사)

Korean Society of Earth and Exploration Geophysicists (한국지구물리·물리탐사학회)
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Laterally Constrained Inversion of GREATEM data

지상 송신원 항공 전자탐사 자료의 횡적 제한 역산

  • Cho, In-Ky (Division of Geology and Geophysics, Kangwon National University) ;
  • Jang, Je-Hun (Division of Geology and Geophysics, Kangwon National University) ;
  • Yi, Myeong-Jong (Mineral Resources Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Rim, Hyoung-Rae (Mineral Resources Division, Korea Institute of Geoscience and Mineral Resources)
  • 조인기 (강원대학교 지질.지구물리학부) ;
  • 장제훈 (강원대학교 지질.지구물리학부) ;
  • 이명종 (한국지질자원연구원 광물자원연구부) ;
  • 임형래 (한국지질자원연구원 광물자원연구부)
  • Received : 2016.11.29
  • Accepted : 2017.01.23
  • Published : 2017.02.28

Abstract

Recently, the grounded electrical-source airborne transient electromagnetic (GREATEM) system with high power source was introduced to achieve deeper investigation depth and to overcome high noise level. Although the GREATEM is a transient electromagnetic system using a long grounded wire as the transmitter, GREATEM data have been interpreted with 1D earth models because 2D or 3D modeling and inversion of vast airborne data are complicated and expensive to calculate. Generally, 1D inversion is subsequently applied to every survey point and combining 1D images together forms the stitched conductivity-depth image. However, the stitched models often result in abrupt variations in neighboring models. To overcome this problem, laterally constrained inversion (LCI) has been developed in inversion of ATEM data, which can yield layered sections with lateral smooth transitions. In this study, we analysed the GREATEM data through 1D numerical modeling for a curved grounded wire source. Furthermore, we developed a laterally constrained inversion scheme for continuous GREATEM data based on a layered earth model. All 1D data sets and models are inverted as one system, producing layered sections with lateral smooth transitions. Applying the developed LCI technique to the GREATEM data, it was confirmed that the laterally constrained inversion can provide laterally smooth model sections that reflect the layering of the survey area effectively.

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Acknowledgement

Supported by : 강원대학교, 한국지질자원연구원

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