• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.71-73
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• 2005

• Economic and Environmental Geology
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• v.19 no.4
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• pp.243-264
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• 1986

This work is a metallogeny on gold-silver deposits in South Korea based on the close examination of the author's own data and a broad review of existing literature available. The metallogenic epochs in Korea are temporarily connected with the history of tectonism and igneous activities, and are identified as the Precambrian, Paleozoic, Jurassic to early Cretaceous, late Cretaceous to early Tertiary, and Quaternary epochs, whereas the metallogenic provinces are spatially associated with some of the felsic to intermediate igneous rocks, lacking mineralization related to basic and ultrabasic rocks. The metallogeny on the gold-silver deposits is mostly related to the granitic rocks intrusives. Epigenetic gold-silver mineralization in South Korea ranges in metallogenic epochs from Precambrian through Triassic, Jurassic and Cretaceous to Eocene (?), in genetic types from hypothermal through mesothermal and epithermal quartz-sulfide veins to volcanogenic stockworks, with some disseminated types. Reporting on metallic association from gold without silver, gold-silver, silver-gold, silver without gold, and gold or silver as a by-product from other metallic ores. The most representative genetic types and metal associations of gold-silver deposits are hydrothermal quartz veins associated with the Daebo and Bulgugsa granitic magmatism. The most closely associated paragenetic metallic minerals in gold-silver hydrothermal quartz-sulfide vein type deposits are: copper, lead, zinc, pyrite and arsenopyrite. More than 560 gold-silver mines are plotted in the distribution map grouped within the 10 different metallogenic provinces of South Korea. Specific mineralizations with related mineral association in both sulfides and gangues observed selected from 18 Korean and 8 Japanese Au-Ag deposits. The 7 selected individual gold-silver mines representing specific mineralization types are described in this report.

• Economic and Environmental Geology
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• v.39 no.5 s.180
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• pp.567-581
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• 2006

The Au-Ag lode deposits in South Korea are closely associated with the Mesozoic granitoids. Namely, the Jurassic deposits formed in mesozonal environments related to deep-seated granitoids, whereas the Cretaceous ones were developed in porphyry-related environments related to subvolcanic granitoids. The time-space relationships of the Au-Ag lode deposits in South Korea are closely related to the changing plate motions during the Mesozoic. Most of the Jurassic auriferous deposits (about $165{\sim}145$ Ma) show fluid characteristics typical of an orogenic-type gold deposits, and were probably generated in a compressional to transpressional regime caused by an orthogonal to oblique convergence of the Izanagi Plate into the East Asian continental margin. On the other hand, strike-slip faults and caldera-related fractures together with subvolcanic activity are associated with major strike-slip faults reactivated by a northward (oblique) to northwestward (orthogonal) convergence, and probably have played an important role in the formation of the Cretaceous Au-Ag lode deposits (about $110{\sim}45$ Ma) under a continental arc setting. The temporal and spatial distinctions between the two typical Mesozoic deposit styles in South Korea probably reflect a different thermal episodes (i.e., late orogenic and post-orogenic) and ore-forming fluids related to different depths of emplacement of magma due to regional changes in tectonic environment.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.05a
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• pp.17-20
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• 1997

이 연구에서는 국내에 산재되어 있는 금속광산들에 대한 토양환경오염을 조사하고 적절한 환경처리를 위한 기초자료를 제공하기 위하여 대표적인 연-아연광산, 동광산 및 금-은광산을 대상으로 As. Cd, Cu, Pb, Zn 등의 오염규모와 분산정도를 규명하고자 하였다. 연구대상지역으로 삼보 연-아연강산, 달성 동-텅스텐광산 그리고 구봉, 삼광, 금왕 금-은광산을 선정하여 이들 광산 주변에서 토양을 채취하여 화학분석을 실시하였다. 그리고 연속추출법을 이용하여 토양중에 존재하는 중금속의 존재형태를 규명하였으며 화학분해방법에 따른 중금속의 추출정도를 고찰하기 위하여 강산을 이용한 분해방법과 토양환경보전법에 제시된 방법을 비교하였다. 화학분석 결과, 삼보광산 주변의 상부토양 (0-15cm 심도)에서는 평균 11.8 $\mu\textrm{g}$/g Cd, 208 $\mu\textrm{g}$/g Cu, 2,700 $\mu\textrm{g}$/g Pb, 8,300 $\mu\textrm{g}$/g Zn이 검출되었으며 일부 농경지에서는 토양환경보전법의 우려기준을 초과하는 중금속이 검출되어 광산활동에 의한 토양오염이 심각함이 조사되었다. 달성광산 주변 토양에서도 다량의 중금속이 검출되었으며 (평균 4.4 $\mu\textrm{g}$/g Cd, 1,950 $\mu\textrm{g}$/g Cu, 1,030 $\mu\textrm{g}$/g Pb, 419 $\mu\textrm{g}$/g Zn) 특히 As (평균 2,500 $\mu\textrm{g}$/g)의 오염이 심각하였다. 그리고 대표적인 금은광산인 구봉, 삼광 및 금왕광산에서는 광미와 선광장 주변에서 다량의 중금속과 As가 검출되었다. 이 연구 결과, 이들 점오염원에 대한 오염정도가 심각하므로 이를 적절하게 처리할 수 있는 오염복구사업이 실시되어야할 것으로 판단된다.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.1-15
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• 2008

The Cretaceous Gajok gold-silver deposit within porphyry granite is located nearby the Cretaceous Pungam basin at the northeastern area in Republic of Korea. The Gajok gold-silver deposit is distinctively composed of a multiple-complex hydrothermal veins with comb, crustiform chalcedony quartz and vug textures, implying it was formed relatively shallower depth. The hypogene open-space filling veins could be divided into 5 paragenetic sequences, increasing tendency of Ag-rich electrum and Ag-phases with increasing paragenetic time. Electrum with high gold contents (${\sim}50$ atomic % Au) as well as sphalerite with high FeS contents (${\sim}6$ mole % FeS) are representative ore minerals in the middle stage. The late stage is characterized by silver-phase such like native silver and/or argentite, coexisting with Ag-rich electrum ($10{\sim}30$ atomic % Au) and Fe-poor sphalerite (< 1 mole % FeS). The ore-forming fluids evolution started at relatively high temperature and salinity (${\sim}360^{\circ}C$, ${\sim}7\;wt.%$ eq. NaCl) and were evolved by dilution and mixing mechanisms on the basis of fluid inclusion study. The gold-silver mineralization proceeded from ore-forming fluids containing greater amounts of less-evolved meteoric waters(${\delta}^{18}O$; $-0.6{\sim}-6.7\;%o$). These results imply that gold-silver mineralization of the Cretaceous Gaiok deposit formed at shallow-crustal level and could be categorized into low-sulfidation epithermal type, related to Cretaceous igneous activity.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.407-416
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• 1997

Soil, tailings, stream sediment and surface water samples collected in the vicinity of the Geumwang Au-Ag mine were analyzed in order to investigate the pollution level of heavy metals and to determine the dispersion patterns. Although the maximum concentrations of soils collected at the flotation plant and tailings dam were 9,270 ppm As, 17 ppm Cd, 1,480 ppm Cu, 10,080 ppm Pb and 18,400 ppm Zn, dispersion of heavy metals were limited in the vicinity of the flotation plant and tailings dam. This may be due to high pH values (> 8.0) of the soils by flotation solution for mineral processing. The pH values of water samples near the flotation plant and tailings dam were over 8.0 and Cd, Cu and Zn concentrations were not detected. The waters in the vicinity of Geumwang mine generally belong to a $Ca^{2+}-SO_{4}{^{2-}}$ $(HCO_3{^-})$ type.

• Economic and Environmental Geology
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• v.29 no.2
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• pp.119-127
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• 1996

Electrum-sulfide minerals of the Namsan Au-Ag mine were deposited in two stages of quartz and calcite veins that fill fault planes in Mesozoic granitic rocks (230~155 Ma). The K/Ar radiometric dating of hydrothermal sericite indicates that mineralization is early Cretaceous age ($127{\pm}3.0Ma$). Mineralogic, fluid inclusion and sulfur isotopic data show that ore minerals were deposited at temperatures between $340^{\circ}C$ and $200^{\circ}C$ from fluid with salinities of 3 to 6 equiv. wt % NaCl. Evidence of fluid boiling (and $CO_2$ effervescence) indicates a maximum pressures of 100 bars. The formation temperature and $fs_2$, of Au-mineralization from the Namsan mines are mainly $280{\sim}230^{\circ}C$ and $10^{-11}{\sim}10^{-13}$ atm, respectively. Au deposition was likely a result of boiling caused to chemical change (pH, $f_{O2}$, ${\Sigma}_{H_2S{\cdot}{\cdot}}$) of ore-fluids. Sulfur isotope composition of sulfide minerals (${\delta}^{34}S=5.1$ to 8.2‰) are consistent with ${\delta}^{34}S_{{\Sigma}{H2S}}$ value of +6 to +7‰, suggesting an igneous source of sulfur partially mixed with wall-rock sulfur.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.383-395
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• 2008

To enhance the grade and recovery rate of the gold/silver ores which yield at Philippine Mankayan mine, we studied the characteristics which are the geologic and mineralogical features of gold and silver ore, the liberation by crushing and grinding, the separation by sieving and shaking table. Gold/silver ore is composed of the sulfide minerals like pyrite, sphalerite, galena; and the gangue minerals which is quartz, clay. Gold/silver element are mainly contained in a sulfide minerals like pyrite, sphalerite and galena. To increase the liberation rate of sulfide minerals containing gold/silver element, the gold/silver ore has to be grounded under $100{\mu}m$ very finely because the crystal size of sulfide minerals is distributed from $1{\mu}m$ to $100{\mu}m$. The liberation rate of gold/silver ore increases to 92% when the particle size ($d_{90}$) of ore is grounded below $100{\mu}m$ by jaw crusher $\to$ cone crusher $\to$ rod mill by steps. The grade and recovery of sulfide minerals could not be enhanced by sieving separation because those crystal size is distributed homogeneously below $100{\mu}m$. But, when we separated the sieved ore using shaking table, the gold and silver grade increased to 40 ppm and 140 ppm, respectively. Then the recovery rate of gold reach almost 100% but that of silver is no more that 50%.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.221-229
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• 1995

The heavy metal contents and their dispersion patterns in stream water, stream sediments, land plants and aquatic larvae collected from the hydrologic system flowing via the wasted ore dump of the Moak Au-Ag mine were investigated systematically in order to evaluate the environmental impacts of the abandoned metal mine. The heavy metal content increases abruptly in the vicinity of the wasted ore dump, then attenuated with increasing distance from the mine area. Attenuating rates were stream water > stream sediments > land plants > aquatic larvae. On the other hand, the cumulative content of heavy metals was stream sediments >aquatic larvae > land plants > stream water. Each element tends to be enriched selectively according to media; Zn > Cu > Cd > Pb in stream water, Zn > Pb > Cu > Cd in stream sediments and land plants, and Zn > Cu > Pb > Cd in aquatic larvae. These results show that the degree of enrichment and dispersion of pollutant extruded from the wasted ore dump are different according to elements and media, and that the circulation system of materials of each medium is different. The heavy metals, especially Cu, Pb and Zn, of polluted downstream sediments occur in high proportions of Fe-Mn oxides and organic bounded forms, which show high potential of a secondary pollution source. The content of heavy metals and their dispersion patterns in stream sediments are different from those of ten years ago; pollution levels of heavy metals were degraded in various ranges. The Zn and Cu-polluted areas were widened whereas Fe and Pb-polluted areas were reduced. In crops collected from the farm lands in downstream area, the pepper was more concentrated in all heavy metal than rice. The pepper showed some contaminated level in Cu(9.7ppm) and Zn(149ppm), and the rice in Zn(90ppm). However, both crops showed no significant level in Cd(<0.2ppm) and Pb(<0.5ppm).

• Economic and Environmental Geology
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• v.43 no.5
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• pp.491-503
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• 2010

Geochemical characteristics of the Moisan epithermal gold-silver deposit with total 140 samples in Haenam area, Jeollanamdo were studied by using multivariate statistical analysis (correlation analysis, factor analysis and cluster analysis). The correlation analysis reveals that Ag, Cu, Bi, Te are highly correlated with Au in the both non-mineralized and mineralized zone. It is resulted from the presence of Au-Ag bearing minerals (electrum, sylvanite, calaverite and stuezite) and non Au-Ag containing minerals (chalcopyrite, tellurobismuthite and bismuthinite). Mo shows relatively much higher correlation at the mineralized zone (0.615) than non-mineralized zone (0.269) which implies Mo content is strongly affected by Au-mineralization. While Mn, Cs, Fe, Se correlated with Au at the nonmineralized zone, they have negative correlation at the mineralized zone. Therefore, they seem to be eluviated elements from the host rock during gold mineralization. Sb is enriched during the gold mineralization showing high correlation at the mineralized zone and negative correlation at the non-mineralized zone. According to the factor analysis, Se, Ag, Cs, Te are the indicators of gold mineralization presence due to the strong affection of gold content in the non-mineralized zone. In the mineralized zone, on the other hand, Mo, Te and Sb, Cu are the indicators of gold and silver mineralization, respectively. While the cluster analysis reveals that Cd-Zn-Pb-S, Bi-Fe-Cu-Mn, Se-Te-Au-Cs-Ag, As-Sb-Ba are the similar behavior elements groups in the non-mineralized zone, Cd-Zn-Mn-Pb, Fe-S-Se, As-Bi-Cs, Ag-Sb-Cu, Au-Te-Mo are the similar behavior elements groups in the mineralized zone. Using multivariate statistical analysis as mentioned above makes it possible to compare the behavior of presented minerals and difference of geochemical characteristics between mineralized and non-mineralized zone. Therefore, it will be expected a useful tool on the similar type of mining exploration.