3차원 전기비저항탐사에 의한 카르스트 지역에서의 공동탐지

Detection of cavities in a karst area by means of a 3D electrical resistivity technique

  • 박삼규 (한국지질자원연구원 광물자원연구본부) ;
  • 김창렬 (한국지질자원연구원 광물자원연구본부) ;
  • 손정술 (한국지질자원연구원 광물자원연구본부) ;
  • 이명종 (한국지질자원연구원 광물자원연구본부) ;
  • 김정호 (한국지질자원연구원 광물자원연구본부)
  • Park, Sam-Gyu (Mineral Resources Research Division, Korea Institute of Geoscience & Mineral Resources (KIGAM)) ;
  • Kim, Chang-Ryol (Mineral Resources Research Division, Korea Institute of Geoscience & Mineral Resources (KIGAM)) ;
  • Son, Jung-Sul (Mineral Resources Research Division, Korea Institute of Geoscience & Mineral Resources (KIGAM)) ;
  • Yi, Myeong-Jong (Mineral Resources Research Division, Korea Institute of Geoscience & Mineral Resources (KIGAM)) ;
  • Kim, Jung-Ho (Mineral Resources Research Division, Korea Institute of Geoscience & Mineral Resources (KIGAM))
  • 발행 : 2009.02.28

초록

이 연구는 한국 남서쪽에 위치한 무안군 용월리의 카르스트 지역에서 지하 공동 탐지를 위하여 3차원 전기비저항탐사의 적용성을 시험한 것이다. 현장 조사지역은 과거에 지반침하가 발생하였으며, 지하 공동은 충적층 하부에 분포하고 있는 석회암내에서 발견된다. 석회암 공동은 대부분 지하수와 점성토로 충진 되어 있기 때문에 주변의 기반암에 비하여 전기비저항이 상대적으로 낮게 나타난다. 이 연구 결과에 의하면 시추공에서 인식되고 있는 공동 분포대가 저비저항대와 일치하고 있으며, 이로부터 3차원 전기비저항탐사가 카르스트 지역에서의 지하 공동을 탐지하고 영상화 하는데 매우 유용함을 입증했다.

In this study, we examined the applicability of a 3D electrical resistivity technique for the probing of underground cavities at a field test site in a karst area in Yongweol-ri, Muan-gun, in the south-western part of the Korean peninsula. At the test site, where the ground has subsided in the past, underground cavities are commonly found in the limestone bedrock, which is overlain with alluvial deposits. The limestone cavities at the test site are mostly filled with groundwater and clay; hence, they show levels of electrical resistivity that are significantly lower than those of the surrounding host bedrock. The results of this study demonstrate that the zones of low resistivity correspond to the zones of the cavities identified in the boreholes at the site, and that our 3D electrical resistivity survey is a very effective tool for detecting and mapping underground cavities in a karst area.

키워드

참고문헌

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