Time-lapse Inversion of 2D Resistivity Monitoring Data

2차원 전기비저항 모니터링 자료의 시간경과 역산

  • 김기주 (강원대학교 지구물리학과) ;
  • 조인기 (강원대학교 지구물리학과) ;
  • 정재형 (한국건설기술연구원 국토지반연구부)
  • Published : 2008.11.30

Abstract

The resistivity method has been used to image the electrical properties of the subsurface. Especially, this method has become suitable for monitoring since data could be rapidly and automatically acquired. In this study, we developed a time-lapse inversion algorithm for the interpretation of resistivity monitoring data. The developed inversion algorithm imposes a big penalty on the model parameter with small change, while a minimal penalty on the model parameter with large change compared to the reference model. Through the numerical experiments, we can ensure that the time-lapse inversion result shows more accurate and focused image where model parameters have changed. Also, applying the timelapse inversion method to the leakage detection of an embankment dam, we can confirm that there are three major leakage zones, but they have not changed over time.

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