Electric and Electromagnetic Surveys of the Hongseong Fault Zone

홍성 단층대에서의 전기, 전자 탐사 연구

  • Kwon, Byung-Doo (Department of Earth Science Education, Seoul National University) ;
  • Lee, Heui-Soon (Department of Science Education, Gyeongin National University of Education) ;
  • Park, Gye-Soon (Department of Earth Science Education, Seoul National University) ;
  • Oh, Seok-Hoon (Marine Meteorology & Earthquake Research Lab, Meteorogical Reseorch Institute) ;
  • Lee, Choon-Ki (Department of Earth Science Education, Seoul National University)
  • 권병두 (서울대학교 사범대학 지구과학교육과) ;
  • 이희순 (경인교육대학교 과학교육과) ;
  • 박계순 (서울대학교 사범대학 지구과학교육과) ;
  • 오석훈 (기상연구소 해양기상지진연구실) ;
  • 이춘기 (서울대학교 사범대학 지구과학교육과)
  • Published : 2003.06.30


We have investigated the electric resistivity structure of the fault zone located in the Hongseong area where a big earthquake with M 5.0 occurred in 1978. Usually, Electric and Electromagnetic methods are broadly operated in the field of engineering works since these methods are effective to understand the distribution of geological weak zones - fault or fracture zones. We have conducted the dipole-dipole array resistivity method and MT(magnetotelluric) method and interpreted the resistivity distribution of the fault zone with the aid of various inversion methods. An MT survey was performed at 18 points along a 2.9 km survey line perpendicular to the fault line and a magnetic dipole source was used to enhance the S/N ratio in the high frequency. A Electric dipole-dipole array resistivity survey with the dipole length of 50 meters was carried out perpendicular to the fault. In view of two survey results, the fault marks the boundary between two opposite resistivity structures, especially the low resistivity zone is exhibited deeply through the prospective fault line. The result that the low resistivity zone is located at the center of the fault zone corresponds with the fact that the fault zone of the Hongseong area is active. We expect these results to provide basic information about the physical properties of fault zones in Korea.


  1. 이종혁. 김성수, 1963, 한국지질도 1:50,000 홍성도폭, 국립 지질조사소.
  2. 이희순, 송윤호, 1997, 전기장 또는 자기장 송신원을 이용한 벡터 CSMT, 자원환경지질, 30(5), 451-458
  3. Constable, S. C., Parker, R. L., and Constable, C. G., 1987, Occam's inversion: A practical algorithm for generating smooth models from electromagnetic sounding data. Geophysics, 52, 289-300 https://doi.org/10.1190/1.1442303
  4. deGroot-Hedlin, C., Constable, S., 1990, Occam's inversion to generate smooth, two-dimensional models from magnetotelluric data. Geophysics, 55, 1613-1624 https://doi.org/10.1190/1.1442813
  5. Fraser-Smith, A. C., Bemardi, A., McGill, P. R., Ladd, M. E., Helliwell, R. A., and Villard, Jr. 0. G., 1990, Lowfrequency magnetic field measurements near the epicenter of the ML 7.1 Loma Prieta earthquake: Geophysical Research Letters, 17, 1465-1468 https://doi.org/10.1029/GL017i009p01465
  6. Johnston, M. J. S., Mueller, R. J., and Sasai, Y., 1994, Magnetic field observations in the near-field the 28 june 1993 Mw 7.3 landers, california, earthquake, Bulletion of the Scismological Society of America. 84, 792-798
  7. Lee, K. and Chung, T. W., 1985, A gravity survey of the Hongsung Area. The Journal of the Geological Society of Korea, 21, 127-132
  8. Lee, K., Jeong B. and Kim, K. H., 1986, Seismicity of the Korean peninsula (I): Seismicity of the Hongsung Area. The Journal of the Geological Society of Korea, 22, 164-175
  9. Mazella, A., Morrison, H. F., 1974, Electrical resistivity variations associated with earthquakes on the San Andreas Fault: Science, 185, 855-857 https://doi.org/10.1126/science.185.4154.855
  10. Rodi, W., Mackie, R. L., 2001, Nonlinear conjugate gradients algorithm for 2-D magnetotelluric inversion. Geophysics, 66,174-187 https://doi.org/10.1190/1.1444893
  11. Singh, R. P., Rankin, D, 1985, The application of VHF measurements to earthquake prediction, Geophysical Prospection, 33, 1232-1239 https://doi.org/10.1111/j.1365-2478.1985.tb01361.x
  12. Smith, J. T, Booker, J. R., 1991, Rapid inversion of twoand three-dimensional magnetotelluric data. Jouenal of Geophysical Research, 96, 3905-3922 https://doi.org/10.1029/90JB02416
  13. Vozoff, K., 1991, The magnetotelluric method. In Nabighian, M. N., (ed), Electromagnetic methods in applied geophysics-applications, vol. 2, part B, Society of Exploration Geophysicists, 641-711
  14. Yi, M.J. Kim, J.H, 1998, Enhancing resolving power of the least-squares inversion with active constraint balancing: 68th SEG Annual meeting (U.S.A)
  15. Zonge, K. L., Hughes, L. J., 1991, Controlled source audio-frequency magnetotellurics. In Nabighian, M. N., (ed), Electromagnetic methods in applied geophysicsapplications, vol. 2, part B, Society of Exploration Geophysicists, 713-809