Application of Two-Dimensional Boundary Condition to Three-Dimensional Magnetotelluric Modeling

3차원 MT 탐사 모델링에서 2차원 경계조건의 적용

  • Han, Nu-Ree (Department of Energy Systems Engineering, Seoul National University) ;
  • Nam, Myung-Jin (Department of Petroleum and Geosystems Engineering, The University of Texas at Austin) ;
  • Kim, Hee-Joon (Department of Energy Resources Engineering, Pukyong National Universiy) ;
  • Lee, Tae-Jong (Geological Research Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Song, Yoon-Ho (Geological Research Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Suh, Jung-Hee (Formerly Department of Civil, Urban and Geosystem Engineering, Seoul National University)
  • 한누리 (서울대학교 에너지시스템공학부) ;
  • 남명진 ;
  • 김희준 (부경대학교 에너지자원공학과) ;
  • 이태종 (한국지질자원연구원 국토지질연구본부) ;
  • 송윤호 (한국지질자원연구원 국토지질연구본부) ;
  • 서정희 (서울대학교 지구환경시스템공학부)
  • Published : 2008.11.30

Abstract

Assigning an exact boundary condition is of great importance in three-dimensional (3D) magnetotelluric (MT) modeling, in which no source is considered in a computing domain. This paper presents a 3D MT modeling algorithm utilizing a Dirichlet condition for a 2D host. To compute boundary values for a model with a 2D host, we need to conduct additional 2D MT modeling. The 2D modeling consists of transverse magnetic and electric modes, which are determined from the relationship between the polarization of plane wave and the strike direction of the 2D structure. Since the 3D MT modeling algorithm solves Maxwell's equations for electric fields using the finite difference method with a staggered grid that defines electric fields along cell edges, electric fields are calculated at the same place in the 2D modeling. The algorithm developed in this study can produce reliable MT responses for a 3D model with a 2D host.

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