북부 소백산 육괴 지역에 부존하는 광산의 열수 금-은 광화작용

• 발행기관: 대한자원환경지질학회
• 저자명: 윤성택 지세정 소칠섭 허철호
• 간행물 정보: 『자원환경지질』31권 5호, 389~398쪽, 전체 10쪽
• 주제분류: 자연과학 > 지질학
• 파일형태: PDF
• 발행일자: 1998.10.30

영문 초록

The Au-Ag deposit of the Oknam mine occurs as gold-silver-bearing rhodochrosite veins in biotite schist and phyllite of the Precambrian Yulri Group. Fove stages of ore deposition are recognized, each showinf a definite mineral assemblage. General mineral parageneses in veins (stage III) associated with gold and silver vary inwardly from the vein margin: arsenopyrite+pyrite→sphalerite+chalcopyrite+galena+gold→galena+Ag-bearing minerals. Fluids inclusion data indicate that temperature and salinity of ore fluids overally decreases with time: 345˚∼240℃ and 3.4∼7.8 wt. % NaCl equiv during stage I (quartz vein mineralization), 313˚∼207℃ and 2.3∼8.7 wt.% NaCl equiv during manganese-bearing carbonate stages (II and III), and 328˚∼213℃ and 3.6∼5.4 wt.% NaCl during stage IV (quartz vein mineralization). The ore fluids probably evolved through repeated pulse of boiling and later mixing with cooler and more dilute meteoric waters. Fluid inclusion data and geologic arguments indicate that pressures during the mineralization were in the range of 90 to 340 bars. Gold occurs as silver-rich electrums (21 to 29 atom.% Au) and was deposited at temperatures between 300˚and 240℃. thermochemical calculations suggest that gold was deposited as a combined result of increase in pH and decreases in temperature, fs₂and fo₂.

키워드

옥남 소백산육괴 선캠브리아기 율리층 광물침전기 광화유체 염농도 에렉트럼 석영맥광화작용