• 자원환경지질
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• 제54권2호
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• pp.213-232
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• 2021

Ore criteria at the Sheba Deposit indicate orogenic mineralization type. Rocks and mineral assemblages suggest low formation-temperature of green-schist facies. Pyrite found in two generations; Type1 is irregular grains, contains higher arsenic and gold contents, compared to the relatively younger phase Type2 pyrite, which is composed of euhedral grains, found adjacent to late quartz-carbonate veins or at rims of type1 pyrite. Two gold generations were identified; type1 found included in sulphides (mainly pyrite). The second gold type was remobilized (secondary) into free-lodes within silicates (mainly quartz). Gold fineness is high, as gold contains up to 95 wt. % Au, Ag up to 3.5 wt. %, and traces of Cu, Ni, and Fe. Pyrite type2 contains tiny mineral domains (rich in Al, Mn, Hg, Se, Ti, V, and Cr). Zoning, and replacement textures are common, suggesting multiple mineralization stages. The distribution and relationships of trace elements in pyrite type2 indicate three formation patterns: (1) Al, Mn, Hg, Se, Ti, V, Cr, and Sn are homogeneously distributed in pyrite, reflecting a synchronous formation. (2) As, Ni, Co, Zn, and Sb display heterogeneous distribution pattern in pyrite, which may indicate post-formation existence due to other activities. (3) Au and Ag show both distribution patterns within pyrite, suggesting that gold is found both in microscopic phases and as chemically bounded phase.

• 자원환경지질
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• 제20권4호
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• pp.261-271
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• 1987

Muguk gold deposits are composed of quartz veins emplaced along faults in Mesozoic granodiorite. General strikes and dips of the veins are $N15{\sim}20^{\circ}W$ and $70{\sim}80^{\circ}NE$. Associated ore minerals are pyrite, arsenopyrite, sphalerite, galena, chalcopyrite, pyrrhotite, native silver, argentite, tetrahedrite and electrum. Vein mineral paragenesis is complicated by repeated fracturing, but five distinct depositional stages can be recognized. Electrum grains are associated mainly with sulfide bands formed along both margins of pale pink quartz of stage 3, and with patches of pyrite aggregate of stage 4. Before the close down in 1972, Muguk gold mine yielded more than 8 tons of gold of which major portion was produced from the No.2 vein. No.2 vein, extending about 1,500m laterally, was exploited to a depth of about 750m. In 1984, Young-poong mining company acquired the mining property and began geologic mapping, geochemical and geophysical exploration, diamond drilling and exploration tunnelling around the mine area to seek for other rich gold-bearing quartz veins. As the Samhyungje vein was disclosed to be the most rich vein, exploration works were focussed on the Samhyungje vein. As of August 1987, 22,338m of diamond drilling and 9,652m of exploration tunnelling have been undertaken. Owing to the successful result of exploration, the Muguk mine commenced normal operation on January 1987, treating 5,500 tons of ore per month.

• 자원환경지질
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• 제31권6호
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• pp.463-472
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• 1998

이 연구는 과테말라 에스탄시아 데 라 비르겐 (Estancia de la Virgen) 지역에 분포하는 광화대의 산상과 광물특성을 밝혀내기 위해 수행되었다. 이 연구를 위해 1:2,000 축척의 정밀광상 지질조사가 이루어졌다. 금-은 광화작용은 산 아구스틴 (San Agustin) 단층과 카바나스 (Cabanas) 단층사이의 단층 블럭내에 발달하며 단층구조에 의한 규제를 받았다. 금은 미량에서 부터 최고 72 g/t, 은은 미량에서 초고 180 g/t까지의 품위를 보인다. 정밀광상 지질조사에 의하면 석영맥은 북동방향으로 연장 500 m 이상 추적되며 연속성은 불량하지만 1,000 m 이상 연장되는 양상을 보인다. 석영맥에서의 광물생성순서는 3개 단계를 나눌 수 있다. 1단계에는 황철석, 방연석, 섬아연석, 황동석이 일차 금-은 광물과 수반되며 2단계에는 휘동석, 코벨라이트, 리나라이트와 같은 Cu-Bi-Au-Ag 황화광물이 형성되었으며 이들은 대체로 방연석이나 황동석의 미세구조에 침착-부화되었다. 3단계에는 방연석, 섬아연석의 탄산염화작용, 방연석의 표성부화작용이 지표환경에서 일어났다. 이 과정에서 용탈된 일부 은이 지하수면 근처에서 산화작용이 일어나는 동안 동광석이나 방연석에 침착되었다. 섬아연석과 황동석에서 각기 Fe와 Zn의 함량이 적은 것은 이들 광물이 비교적 저온에서 형성되었음을 의미하며 이는 이전에 연구된 유체포유물의 균일화온도와도 일치한다.