Journal of the Korean Society of Mineral and Energy Resources Engineers (한국자원공학회지)

The Korean Society of Mineral and Energy Resources Engineers (한국자원공학회)
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Weathering Degree Assessment of Tuff Stone Monument Using Reflectance Spectroscopy

반사분광학을 이용한 응회암 석조문화재의 풍화도 평가

  • 현창욱 (서울대학교 공학연구소) ;
  • 박형동 (서울대학교 에너지시스템공학부)
  • Received : 2010.07.07
  • Accepted : 2010.07.23
  • Published : 2010.08.31
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Abstract

Weathering degree assessment of rocks has been conducted with naked-eyes of geologists, microscopic analysis and X-ray analysis methods. Those conventional methods have limitations to produce subjective and biased judgment, destroy of objects and time-consuming procedures, and cannot conduct quantitative, non-destructive and in-situ experiments. To overcome the above mentioned limitations, new non-destructive weathering degree assessment method was developed from the spectral reflectances including the intrinsic and diagnostic absorption features of minerals with the wavelength ranges from visible to near infrared. The non-destructive assessment method was applied to the tuff sculpture and pagoda in Unjusa temple, Hwasun County, Jeollanam-do, Korea, and the weathering degrees were measured on the surface of the monuments. The map of weathering degree corresponded with the trends of the wind directions and rain. The weathering degree assessment method can be applied to the stone monuments composed of various rock types with the advantages of non-destructive and areal measurement.

암석의 풍화도는 지질 전문가에 의한 육안분석, 현미경 관찰, X-선 응용 기법을 통해 평가가 이루어졌으나 이러한 방법은 주관적 해석에 의한 오차 발생, 시료가공으로 인한 대상 손상, 실험실 실험을 위한 시간 소모 등 정량 분석, 비파괴 분석, 현장 적용성의 측면에서 제한이 있다. 본 연구에서는 가시광과 근적외선 파장영 역에서 구성 광물의 고유한 에너지 흡수특성을 나타내는 분광반사특성을 기반으로 암석의 상대적 풍화도를 산정할 수 있는 비파괴 평가기법을 개발하여 기존 기법들의 제한 요소들을 극복하고자 하였다. 본 기법을 전라남도 화순군 운주사에 있는 응회암 기반의 마애불과 석탑을 대상으로 적용하여 측정 지점별 풍화 정도를 산정하고 풍화 지도를 작성한 결과, 강우 및 풍향에 따른 풍화특성과 일치함을 확인할 수 있었다. 본 기법의 비파괴적 특징 및 대상 영역 전체에 대한 풍화 정도 파악이 가능하다는 장점은 향후 다양한 암종의 석조문화재에 대한 풍화도 평가기법으로 적용이 가능할 것으로 기대된다.

Keywords

Acknowledgement

Supported by : 서울대학교 공학연구소

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