지질공학 (The Journal of Engineering Geology)

  • 제27권3호
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  • Pages.323-330
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  • 2017
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  • 1226-5268(pISSN)
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  • 2287-7169(eISSN)
대한지질공학회 (The Korean Society of Engineering Geology)
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음파검층과 밀도검층 자료에서 산출된 이방성 변수를 이용한 지층 구분

Formation Identification using Anisotropic Parameters from Sonic and Density Logs

  • 장성형 (한국지질자원연구원 석유해저연구본부) ;
  • 김태연 (한국과학기술연합대학원대학교 석유자원공학) ;
  • 황세호 (한국과학기술연합대학원대학교 석유자원공학)
  • Jang, Seonghyung (Korea Institute of Geoscience and Mineral Resources, Petroleum and Marine Division) ;
  • Kim, Tae Youn (Korea Institute of Geoscience and Mineral Resources, Geological Environment Division) ;
  • Hwang, Seho (Korea Institute of Geoscience and Mineral Resources, Geological Environment Division)
  • 투고 : 2017.08.31
  • 심사 : 2017.09.28
  • 발행 : 2017.09.30
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초록

지하 지층의 확인은 지표면 지질조사, 시추코어 분석, 시추코어 관찰, 물리검층 자료 분석 등의 다양한 방법을 이용한다. 이 가운데 물리검층 자료는 원위치에서 연속적으로 물성을 제공하므로 시추코어 분석 자료와 더불어 지층의 확인에 활용되고 있다. 본 연구에서는 완전파형 음파검층과 밀도검층 자료에서 이방성 변수를 구하고 이를 이용하여 지층의 구분에 적용하고자 하였다. 톰슨 이방성 변수(${\varepsilon},\;{\delta},\;{\eta}$)는 바쿠스(Backus) 평균법을 P파와 S파 속도, 밀도검층 자료에 적용하여 계산하였다. 이와 같은 방법을 캐나다 블랙풋의 물리검층 자료에 적용한 결과, 12개 구간으로 지층을 구분 할 수 있 수 있었다. 즉, 탄성파 속도 이방성을 반영하는 톰슨 이방성 값의 변화에서 지층의 구분이 가능하였고 지층 구분에 많이 이용하는 자연감마선검층 자료가 없는 경우에도 톰슨 이방성 변수를 이용하여 지층 구분이 가능함을 알 수 있었다.

For the formation identification, surface geological survey, drill core analysis, core description and well log analysis are widely used. Among them well log analysis is a popular method with drill core analysis, since it measures continuously physical properties at in-situ. In this study we calculated Thomsen anisotropic parameters (${\varepsilon},\;{\delta},\;{\eta}$) after applying Backus averaging method to the P wave velocity, S wave velocity, and density logs. The well log data application of Blackfoot, Canada, shows the formation could be divided by 12 layers. This shows that Thomsen anisotropic parameters for identifying formation using anisotropic parameters is useful if there is no natural gamma log that is widely used for the formation identification.

키워드

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