忠淸北道 永同地域 金銀鑛床의 金銀鑛化作用에 관한 硏究

• 영문명: Gold-Silver Mineralization of the Au-Ag Deposits at Yeongdong District, Chung-cheongbuk-Do
• 발행기관: 대한자원환경지질학회
• 저자명: Seon Gyu Choi(崔善奎) Se Jung Chi(池世定) Sung Won Park(朴性元)
• 간행물 정보: 『자원환경지질』21권 4호, 367~383쪽, 전체 17쪽
• 주제분류: 자연과학 > 지질학
• 파일형태: PDF
• 발행일자: 1988.08.30

영문 초록

Most of the gold (-silver) vein deposits at Yeongdong District are mainly distributed in the precambrian metamorphic rocks. Based on the Ag/Au total production and ore grade ratios, the chemical composition of electrum and the associated sulfides, the gold(-silver) deposits at Yeongdong District may be classified into 4 classes: pyrrhotite - type gold deposits( I), pyrite - type gold deposits (IT A; massive vein), pyrite - type gold deposits (II B; nonmassive vein) and argentite - type gold - silver deposits(III). The chemical study on electrum(including native gold) revealed that Au content (2.8 to 92.4 atomic%) of electrums varies very widely for different classes of deposits. The Au content of electrum associated with pyrrhotite (Class I), ranging from 47.1 to 92.4 atomic% Au, is clearly higher than that associated with pyrite (Classes IIA, IIB and III). In contrast, classes I, II, and III deposits do not show clear differences in Au content of electrum. In general, pyrrhotite - type gold deposits(I) are characterized by features such as simply massive vein morphology, low values in the Ag/Au total production and ore grade ratios, the absence or rarity of silver - bearing minerals except electrum, and distinctively simple mineralogy. Although the geological and mineralogical features and vein morphology of pyrite - type gold deposits(IIA)are very similar to those of pyrrhotite - type gold deposits (I), Class II A deposits reveal significant differences in the associated iron sulfide (i. e. pyrite) with electrum and Au content of electrum. The Ag/Au total production and ore grade ratios from Class II A deposits are relatively slightly higher than those from Class I deposits. Pyrite - type gold deposits(II B) and argentite - type gold - silver deposits (III) have many common features; complex vein morphology, medium to high values in the Ag/Au total production and ore grade ratios and the associated iron sulfide (i. e. pyrite). In contrast to Class II B deposits, Class III deposits have significantly high Ag/Au total production and ore grade ratios. It indicates distinct difference in the abundance of silver minerals (i. e. native silver and argentite). The fluid inclusion analyses and mineralogical data of electrum tarnish method indicate that the gold mineralization of Classes I and II A deposits was deposited at temperatures between 230° and 370℃, whereas the gold (-silver) mineralization of Classes ITB and ill formed from the temperature range of 150°-290℃. Therefore, Classes I and IT A deposits have been formed at higher temperature condition and/or deeper positions than Classes IIB and III.

목차

Abstract

서언

지질광상 개요

광석의 금은비와 광석광물의 특징

에렉트럼의 화학조성

광상의 분류

금은광상의 생성환경

결언

참고문헌