광물자원 탐사기법 : 열수변질대 탐사에서 단파장적외선(SWIR) 분광분석법
최선규, 김창성, 박상준
요약 : 단파장적외선(SWIR) 분광법은 광물자원의 탐사시 열수변질대의 분포양상을 규명함으로써 광상의 생성 모델에 따른 부존 가능지역을 예측하는 탐사기법으로, 암석 토양 등 다양한 시료에 적용할 수 있다. 분광분석시 암석시료의 함수량 및 입도차이 등 측정 상태에 따른 정량성의 오차요인은 스펙트럼 변화에 전반적으로 미약하게 작용하여 현장조건에서 열수변질대의 광물상의 검증과 함께 실시간 분석이 가능하다. 또한, 2성분계 광물조합에 대한정량실험 결과 광상 유형별 다양한 변질대의 전형적인 광물인 명반석-카올리나이트, 카올리나이트-일라이트, 일라이트-녹니석의 조합에서는 ±10% 이내 오차범위로 정량성이 우수한 것으로 확인되었다.
주요어 : 단파장적외선 분광법, 열수변질대, 광상탐사, PIMA
Abstract : The application of portable short-wave infrared(SWIR) spectrometer such as the PIMA SP has been used to define the alteration zones in mineral exploration. This technique allows rapid field-based identification of hydrothermal alteration minerals and detailed examination of drill hole logging. The SWIR results can be discriminated by wavelength and intensity of relevant absorption features under hydrated and various surface condition of specimens. The SWIR spectroscopy is capable of quantitatively estimating abundances of alteration mineral, and determining chemical composition in minerals such as chlorite. The known binary mixtures using mineral standards reveal that the estimated precision and accuracy of the empirical spectral method is capable of identifying alunite-kaolinite, kaolinite-illite, and illite-chlorite assemblages within an error of less than 10 percent.
Key words : SWIR, hydrothermal alteration, exploration, PIMA
1. 서 언
2. 단파장적외선 분광분석법
참고문헌
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