Effect of geological characteristics on differential weathering of low-graded metasedimentary rock slopes

저변성퇴적암 사면에서 지질특성이 차별풍화에 미치는 영향

  • Jeong, Hae-Geun (K-water Institute, Korea Water Resources Corporation) ;
  • Seo, Yong-Seok (Department of Earth and Environmental Sciences, Chungbuk National University) ;
  • Ihm, Myung-Hyeok (Department of Geotechnical Engineering for Disaster Prevention, Daejeon University)
  • 정해근 (한국수자원공사 K-water 연구원) ;
  • 서용석 (충북대학교 지구환경과학과) ;
  • 임명혁 (대전대학교 지반방재공학과)
  • Received : 2013.05.06
  • Accepted : 2013.05.21
  • Published : 2013.07.31


This study evaluates correlation between petrographic characteristics and weathering grade of low-graded metasedimentary rocks mainly consisting of phyllite. Weathering grade of rock material was determined based on the results of geological survey. The Schmidt hammer test was carried out to obtain estimates of strength of rock materials. Point counting and microscopic observation were also conducted to analyze mineral composition and to measure spacing of foliation for 9 rock specimens. As a result of microscopic analysis, as the weathering grade was lower, the quartz was found more in quantity, consequently making rock stronger against weathering process. On the other side, lower weathering grade of rock resulted in less content of mica which is weak against weathering process. In addition, the rock materials with closer foliation spacing are found to be weaker in strength and have higher weathering grade.


Supported by : 한국연구재단


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