거창지역의 쥬라기 화강암에 발달된 결의 특성

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박덕원
Park, Deok-Won

  • 투고 : 2014.04.21
  • 심사 : 2015.05.26
  • 발행 : 2015.09.30

초록

거창지역의 쥬라기 화강암에 대하여 결의 특성에 대한 분석을 실시하였다. 미세균열에 의하여 형성된 구조적 이방성을 주로 논의하였다. 미세균열의 분포상은 박편의 확대사진(${\times}6.7$)에서 잘 확인되었다. 일차 우세 미세균열은 1번 면에 평행하고 이차 우세 미세균열은 2번 면에 평행하다. 이들 1번 결과 2번 결을 형성하는 미세균열은 3번 면상에서 상호 거의 수직을 이룬다. 방향각(${\theta}$)-총 길이($L_t$), 빈도수(N) 및 밀도(${\rho}$)의 도표에서 상기 미세균열의 모수의 곡선형태는 미세균열의 분포상을 반영한다. 빈도수, 길이 및 밀도와 같은 미세균열의 모수들은 1번 결 > 2번 결 > 3번 결의 순서로 나타난다. 이러한 결과는 결의 상대적인 강도를 지시한다. 한편 6개 방향에 따른 압열 인장강도가 측정되었다. 강도와 위의 미세균열의 모수들 사이에는 밀접한 상관성을 보이고 있다. 이러한 전반적인 결과는 포천 및 합천지역의 쥬라기 화강암류에 대한 기존의 연구결과와 부합한다. 박편의 확대사진에 대한 이미지 처리 기법을 수행하였다. 사진 상에서 석영 및 장석 내부에서 발달하는 그레인 1(G1) 미세균열의 배열이 탁월한 분포를 보여준다. 특히 위의 사진에 대한 간단한 이미지 처리를 통하여 각 미세균열 조의 방향각을 용이하게 확인할 수가 있다.

키워드

쥬라기 화강암;결;확대사진;미세균열의 모수;이미지 처리

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피인용 문헌

  1. 1. Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (I) vol.25, pp.1, 2016, doi:10.7854/JPSK.2015.24.3.153
  2. 2. Editorial : 2015, Applied petrology: Dimension stone, Aggregate, Stone cultural heritage vol.24, pp.3, 2015, doi:10.7854/JPSK.2015.24.3.153
  3. 3. Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (II) vol.25, pp.2, 2016, doi:10.7854/JPSK.2015.24.3.153
  4. 4. Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (III) vol.25, pp.4, 2016, doi:10.7854/JPSK.2015.24.3.153

과제정보

연구 과제번호 : 고온 고압 조건하 심부 지열특성 평가기술 개발

연구 과제 주관 기관 : 한국지질자원연구원