Browse > Article

Two-Dimensional Magnetotelluric Interpretation by Finite-Element Method  

Kim, Hee-Joon (Department of Environmental Exploration Engineering, Pukyong National University)
Choi, Ji-Hyang (Department of Energy System Engineering, Seoul National University)
Han, Nu-Ree (Department of Energy System Engineering, Seoul National University)
Lee, Seong-Kon (Groundwater & Geothermal Resources Division, Korea Institute of Geoscience & Mineral Resources)
Song, Yoon-Ho (Groundwater & Geothermal Resources Division, Korea Institute of Geoscience & Mineral Resources)
Publication Information
Geophysics and Geophysical Exploration / v.11, no.2, 2008 , pp. 85-92 More about this Journal
Abstract
Magnetotelluric (MT) methods are widely applied as an effective exploration technique to geothermal surveys. Two-dimensional (2-D) analysis is frequently used to investigate a complicated subsurface structure in a geothermal region. A 2-D finite-element method (FEM) is usually applied to the MT analysis, but we must pay attention to the accuracy of so-called auxiliary fields. Rodi (1976) proposed an algorithm of improving the accuracy of auxiliary fields, and named it as the MOM method. Because it introduces zeros into the diagonal elements of coefficient matrix of the FEM total equation, a pivoting procedure applied to the symmetrical band matrix makes the numerical solution far less efficient. The MOM method was devised mainly for the inversion analysis, in which partial derivatives of both electric and magnetic fields with respect to model parameters are required. In the case of forward modeling, however, we do not have to resort to the MOM method; there is no need of modifying the coefficient matrix, and the auxiliary fields can be elicited from the regular FEM solution. The computational efficiency of the MOM method, however, can be greatly improved through a sophisticated rearrangement of the total equation.
Keywords
MT; 2-D; FEM; MOM; auxiliary fields;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
연도 인용수 순위
1 이춘기, 권병두, 이희순, 조인기, 오석훈, 송윤호, 이태종, 2007, 한반도 횡단 자기지전류 탐사에 의한 상부 지각의 지전기적 구조 연구, 한국지구과학회지, 28, 187-201   과학기술학회마을   DOI
2 송윤호, 이태종, Uchida, T., 2006, 가청주파수 대역 MT 탐사자 료에서 원거리 기준점의 효과, 한국지구시스템공학회지, 43, 44-54
3 Lee, T. J., Lee, S. K., Song, Y., and Uchida, T., 2006, The deep geological structure of Jeju Island from 2-D interpretation of AMT and MT data, Proc. 8th SEGJ Int. Symp., 109-114
4 Uchida, T., Song, Y., Lee, T. J., Lee, S. K., and Lim, S. K., 2006, Far remote reference analysis of MT and AMT data in Jeju Island, Korea, Proc. 10th Int. Symp. RAEG 2006, 75-78
5 Wannamaker, P. E., Stodt, J. A., and Rijo, L., 1986, Twodimensional topographic responses in magnetotellurics modeled using finite elements, Geophysics, 51, 2131-2144   DOI   ScienceOn
6 Sheen, D.-H., Kim, H. J., and Baag, C.-E., 2000, A technique for improving the efficiency of finite element solutions in magnetotelluric modeling, 70th Ann. Internat. Mtg., Soc. Expl. Geophys., Expanded Abstracts, 442-445
7 김희준, 남명진, 한누리, 최지향, 이태종, 송윤호, 서정희, 2004, MT 자료의 3차원 역산 개관, 물리탐사, 7, 207-212
8 Lee, S. K., Kim, H. J., Lee, C.-K., and Song, Y., 2008, MT2DInvMatlab−A program in MATLAB and FORTRAN for two-dimensional magnetotelluric inversion, Computers & Geosicience. (in minor revision)
9 Nam, M. J., Kim, H. J., Song, Y., Lee, T. J., and Suh, J. H., 2006, Three-Dimensional Correction in Magnetotelluric Surveys Using Edge Finite-Element Modeling, Proc. 10th Int. Symp. RAEG 2006, 59-64
10 Smith, J. T., and Booker, J. R., 1991, Rapid inversion of twoand three-dimensional magnetotelluric data, J. Geophys. Res., 96, 3905-3922   DOI
11 이성곤, 송윤호, 조성준, 손정술, 정승환, 2002, 지형을 포함한 MT 탐사 자료의 2차원 모델링과 역산, 물리탐사, 5, 291-298
12 Rodi, W. L., 1976, A technique for improving the accuracy of finite element solutions for magnetotelluric data, Geophys. J. R. astr. Soc., 44, 483-506   DOI