• 자원환경지질
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• 제19권spc호
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• pp.97-102
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• 1986

Concepts on mineral association, mineral paragenesis, and mineralization stage relating to macrostructures of vein filling in ore veins are briefly discussed. As an example of plutonic ore vein, macrostructures of vein filling of plutonic tungsten-tin-copper vein at the Ohtani mine, Kyoto Prefecture, Japan, one of representatives of plutonic tungsten-tin vein related genetically to acidic magmatism of late Cretaceous in the Inner zone of Southwest Japan, are examined. Based on macrostructures of vein filling, three major mineralization stages, are distinguished by major tectonic breaks. Sequence of mineralization, characteristic features of each mineralization stage, and variations of filling temperature and salinity ranges of fluid inclusions in minerals from stage I to stage III are summarized.

• 자원환경지질
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• 제16권3호
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• pp.135-147
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• 1983

The copper deposits in Goseong district, Gyeongnam area are fissure filled copper veins emplaced on Cretaceous Goseong formation and andesitic rocks. Occurrence of ore veins and mineral paragenesis suggest a division of the hydrothermal mineralization into three stages: stage 1, deposition of arsenopyrite, pyrite, quartz, chlorite and epidote; stageII, deposition of pyrite, chalcopyrite, galena, sphalerite, electrum, pyrargyrite, tetrahedrite, silver sulfosalt minerals, quartz, chlorite, sericite and miner amount of calcite; stage III, formation of barren calcite veins. Filling temperature of fluid inclusions in quartz of stage II, range from 260 to 360 C and salinities from 6.2 to 13.6 weight percent NaCi equivalent.

• 자원환경지질
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• 제20권4호
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• pp.223-234
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• 1987

This paper describes the mode of occurrence and mineralogical properties of electrum from the Namseong Gold-Silver deposits, for the purpose of obtaining data on the characteristics of the ore deposits and the behavior of gold and silver during the mineralization. The gangue minerals are quartz, calcite, fluorite. Ore minerals are mainly composed of pyrite, sphalerite, chalcopyrite and galena with minor amount of argentite, electrum, pyrargyrite, native silver and unidenfied mineral(Cu-Fe-Ag-S series). Three stage of mineralization recognized are, from early to later, (I) pyrite-electrum stage (II) sphalerite-chalcopyrite-galena-argentite-electrum stage (III) sulfosalts stage. The filling temperature of fluid inclusions in quartz ranges from $225^{\circ}$ to $335^{\circ}C$. The value of sulfur fugacity estimated by means of electrum-tarnish method ranges from $10^{-11.5}$ to $10^{-14}$ atm. The compositional heterogeneity within a single grain with respect to gold concentration is common in the Namseong electrums Chemical composition of electrum ranges generally between 25~45 atom% Au. Its gold content decreases in late stages of mineralization.

• 자원환경지질
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• 제7권1호
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• pp.23-35
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• 1974

Dalsung Mine, located in Kyungsang puk-do, Korea, is well known as one of the typical breccia pipe filling hydrothermal W-Cu deposit. By homogenization temperature with fluid inclusions in quartz crystals (330 samples were dealt with) by heating stage microscope, two temperature ranges were figured out, one is $154^{\circ}{\sim}267^{\circ}C$ (average $210^{\circ}C$), and the other is $283^{\circ}{\sim}335^{\circ}C$ (average $309^{\circ}C$). Regarding to mineral paragenesis, mineralization of the deposit were thought that former, mesothermal stage, W-Cu mineralization processed through out the ore body and later mineralization were limitted under -4level as katathermal solution with Cu minerals.

• 자원환경지질
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• 제28권1호
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• pp.9-17
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• 1995

The Kamkye Cu-Pb-Zn-Au-Ag deposits occur as quartz veins that filled fault-related fractures of NW system developed in the Cretaceous Gyeongsang basin. Three major stages of mineral deposition are recognized: (1) the stage I associated with wall rock alteration, such as sericite, chlorite, epidote and pyrite, (2) the early stage II of base-metal mineralization such as pyrite, hematite, and small amounts of sphalerite and chalcopyrite. and the middle to late stage II of Cu-As-Sb-Au-Ag-S mineralization, such as sphalerite, chalcopyrite, galena with tetrahedrite, tennantite, pearceite, Pb-Bi-Cu-S system, argentite and electrum. (3) the stage III of supergene mineralization, such as covellite, chalcocite and malachite. K-Ar dating of alteration sericite is a late Cretaceous ($74.0{\pm}1.6Ma$) and it may be associated with granitic activity of nearby biotite granite and quartz porphyry. Fluid inclusion data suggest a complex history of boiling, cooling and dilution of ore fluids. Stage II mineralization occurred at temperatures between 370 to $220^{\circ}C$ from fluids with salinities of 8.4 to 0.9 wt.% NaCl. Early stage II($320^{\circ}C$, 2.0 wt.% NaCl) may be boiled due to repeated fracturing which opened up the hydrothermal system to the land surface, and which resulted in a base-metal sulfide. Whilst the fractures were opened to the surface, mixing of middle-late stage II ore fluids with meteoric waters resulted in deposition of Cu-As-Sb-Au-Ag minerals from low temperature fluids(${\leq}290^{\circ}C$). Boiling of ore fluids may be occured at a pressure of 112 bar and a depth of 412 m. Equilibrium thermodynamic interpretation of sphalerite-tetraherite assemblages in middle stage II indicates that the ore-forming fluid had log fugacities of $S_2$ of -6.6~-9.4 atm.

• 자원환경지질
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• 제29권2호
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• pp.139-150
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• 1996

The Yucheon Bi deposits at Cheongha, Gyeongsangbugdo, is of a middle Paleogene (49 Ma) vein type, and is hosted in sandstone and shale of Banyawal formation in Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, two minera1ization stages were distinguished. The stage I consists of quartz with small amount of chlorite, pyrite, epidote, hal1oysite, vermiculite, serpentine and rutile associated with sericitization. The stage II is characterized by Bi minera1ization such as bismuthinite, Bi-Cu-Pb-S mineral, tetradymite, native gold, pyrite, pyrrhotite, arsenopyrite, wolframite, rutile, hematite, sphalerite, chalcopyrite, galena with alteration of sericite, chlorite, K-feldspar, albite and epidote. Fluid inclusion data indicate that fluid temperature and NaCl equivalent wt.% salinity range from 431 to $150^{\circ}C$ and from 19.2 to 0.18wt.% in the stage II. Evidence of boiling during the base-metal minera1ization indicates pressures 241 to 260 bars. Sulfur fugacity($-log\;f_{S2}$) deduced by mineral assemblages and compositions ranges from 5.1 to 5.7atm in early stage, from > 8.4 atm in middle stage and from 13.5 to 19.3 atm in late stage. It suggests that complex histories of progressive coo1ing, dilution and boiling were occurred by the mixing of the fluids. The ${\delta}^{34}S$, ${\delta}^{18}O$ and ${\delta}D$ data range from 2.5 to 3.9%, -0.5 to -4.1% and -29.7 to -47%, respectively. It indicated that hydrothermal fluids may be magmatic origin with boiling and mixing of meteoric water increasing paragenetic time.

• 자원환경지질
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• 제20권3호
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• pp.169-177
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• 1987

The Manjang copper magnetite-fluorite orebodies are imbedded within the limestone beds of the Hwajonri Formation. The ore deposits are characterized by magnetite-fluorite bearing skarn orebody in the west orebody and copper sulfide veins of the central and main orebodies. This study includes fluid inclusion geothermometry, salinity analysis, stable isotope analysis, and application of phase rule to mineral associations in skarn ore. Ore minerals are closely associated with the skarn silicates such as garnet, wollastonite and epidote. Magnetite and fluorite are remarkable in the west orebody whereas chalcopyrite is dominate in the central and main orebodies where pyrite and pyrrhotite also appear as sulfide gangues. Homogenization temperature and salinity of fluid inclusions are measured ranging between $240^{\circ}C$ and $350^{\circ}C$, 6.3~12.9 wt. percent in quartz and $220^{\circ}C$ and $350^{\circ}C$, 8.5~9.9wt. percent in fluorite, respectively. This indicates that the filling temperature and salinity are higher in quartz than in fluorite with the tendency of both to be linearly decreased suggesting an attribution of meteoric water to the mineralization. $T-fo_2$ diagram in the Ca-Fe-Si system at 1 kb and $Xco_2$=0.02 shows that the mineral assemblages with decreasing temperature are andradite-hedenbergite-calcite, hedenbergite-andradite-quartz, magnetite-andradite-quartz, and magnetite-quartz-calcite, indicating that magnetite crystallizes mostly late skarn stage at lower temperature. According to the carbon and oxygen isotopic values of the host limestone and calcite in ores, the sourec of carbon might be mixture of host limestone and deep seated carbons. Sulfur isotope data imply that ore fluids be relatively homogeneous in sulfur isotopic composition, mainly derived from igneous source.

• Journal of Microbiology and Biotechnology
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• 제31권6호
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• pp.890-901
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• 2021

The 11α-hydroxylation of canrenone can be catalyzed by Aspergillus ochraceus in bioreactors, where the geometry of the impeller greatly influences the biotransformation. In this study, the effects of the blade number and impeller diameter of a Rushton turbine on the 11α-hydroxylation of canrenone were considered. The results of fermentation experiments using a 50 mm four-blade impeller showed that 3.40% and 11.43% increases in the conversion ratio were achieved by increasing the blade number and impeller diameter, respectively. However, with an impeller diameter of 60 mm, the conversion ratio with a six-blade impeller was 14.42% lower than that with a four-blade impeller. Data from cold model experiments with a large-diameter six-blade impeller indicated that the serious leakage of inclusions and a 22.08% enzyme activity retention led to a low conversion ratio. Numerical simulations suggested that there was good gas distribution and high fluid flow velocity when the fluid was stirred by large-diameter impellers, resulting in a high dissolved oxygen content and good bulk circulation, which positively affected hyphal growth and metabolism. However, a large-diameter six-blade impeller created overly high shear compared to a large-diameter four-blade impeller, thereby decreasing the conversion ratio. The average shear rates of the former and latter cases were 43.25 s^-1 and 35.31 s^-1, respectively. We therefore concluded that appropriate shear should be applied in the 11α-hydroxylation of canrenone. Overall, this study provides basic data for the scaled-up production of 11α-hydroxycanrenone.

• 자원환경지질
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• 제35권5호
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• pp.379-393
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• 2002

한반도의 보성-장흥지역에는, 5개의 열수 금(-은)광상이 부존하며, 다음과 같은 특징들을 보여준다: 에렉트럼의 비교적 금이 풍부한 특성; 은-안티모니(끼소)황염광물의 부재; 괴상이며 단순한 광물조성을 지닌 석영맥. 이러한 성질들은 본 지역의 금광화작용이 한반도의 주라기내지 초기 백악기의 중열수형 금광상과 대비가 됨을 지시한다. 유체포유물 연구에 의하면, 본 지역의 광화 1기 석영내 포유물은 0.0~l3.8 wt. % NaCl를 지니고 200~46$0^{\circ}C$의 넓은 온도에서 균질화하며, 광화 2기 방해석내 유체포유물은 1.2~7.9wt. % NaCl를 지니고 15$0^{\circ}C$~254$^{\circ}C$의 온도에서 균질화한다. 이는 시간이 지남에 따라 열수활동이 쇠퇴하면서 열수유체가 냉각되었음을 지시한다. $CO_2$불혼화를 포함한 비등증거는 본 지역의 함금유체의 포획시 압력이 최대 770bar에 해당됨을 지시하고 있다. 본 지역 함금유체의 계산된 황동위원소 조성(${\delta}^34S$_{{\Sigma}S}$=0.2~3.3$\textperthousand$)은 열수유체내 황의 화성기원을 지시하고 있다. 소백산육괴내에는 두 개의 대표적인 중열수형 광화대(영동지역 및 보성-장흥지역)가 부존한다. 영동지역의 황화물의 $\delta$$^{34}S$ 값은 -6.6~2.3$\textperthousand$(평균 -1.4$\textperthousand$, 분석수 66개)이며, 보성-장흥지역의 황화물의 (${\delta}^{34}S값은 -0.7~3.6$\textperthousand$(평균 1.6$\textperthousand$, 분석수 39개)이다. 두 지역의 $\delta$$^{34}$ S값은 대부분의 한반도 금속광상(3~7$\textperthousand$)의 ${\delta}^{34}S값보다 낮다. 그리고, 소백산 육괴내에서는 영동지역의${/delta}^{34}S값이 보성-장흥지역의 ${\delta}^{34}S값보다 낮다. 소백산 육괴내에서(${\delta}^{34}/S값의 차이는 다음과 같은 반응기작에 의해 야기될 수 있다: 1) 두 지역의 주라기 중열수형 금광상에 대해 적어도 두 개의 근원지(두개 모두 화성기원이며, -6$\textperthousand$ 미만 및 2$\pm$2$\textperthousand$의 $\delta$$^{34}$ S값)가 존재, 2) 마그마의 생성 및 상승중 $^{32}S$가 풍부한 황(선캠브리아기의 이토질 긴저암내 황)의 혼합(동화)차이; (3)광화지역까지 상승중 H$_2$S가 풍부한 마그마에서 유래된 황원(${\delta}^{34}/S=2$\pm$2$\textperthousand$)의 산화차이. 두 지역 중열수형광상의 석영내 유체포 유물과 광석광물(특히, 철을 함유한 광석광물)의 상이성을 고려하여, 영동지역의 자류철석이 풍부한 중열수형 광상이 보성-장흥지역의 황철석(-유비철석)이 풍부한 중열수형 광상보다 더욱 높은 온도와 더욱 환원된 유체로부터 생성되었음을 알 수 있다. 현재 두 지역에서 산출되는 선캠브리아 편마암과 고생대 퇴적암의 (${\delta}^{34}S값을 알지 못하므로 두 지역 황동위원소 값의 차이에 대한 원인으로 세 번째 반응기작이 가장 가능성이 크다고 판단된다. 앞으로는, 광석황의 근원을 더욱 체계적으로 규명하기 위해서, 소백산육괴를 포함한 한반도의 기저부를 이루는 선캠브리아 변성암과 고생대 퇴적암의 ${\delta}^{34}S값을 조사할 필요가 있다.

• 자원환경지질
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• 제35권3호
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• pp.203-210
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• 2002

해저 열수 광화작용을 대효할 수 있는 황화물 침니(sulfide chimney)의 성장 메카니즘을 고찰하기 위하여 Juan de Fuca 혜령의 최남단에 위치하는 Cleft segment의 열수장(hydrothermal field)에서 회수한 비활동성이고 황화물과 실리카가 풍부한 침니를 대상으로 광물 및 유체포유물 연구를 수행하였다. 기존 연구에 의하면, Cleft sogment에는 많은 활동성 및 비활동성의 열수 분출구가 존재하는 것으로 보고되어 있다. 연구 대상 침니는 주로 비정질 실리카, 황칠석, 섬아연석 및 섬유아연석(wurtzite)으로 구성되어 있고,소량의 황동석 및 백칠석을 함유하고 있다. 유체통로로 추정되는 침니의 내부는 다공질이며, 비정질의 교질성(colloidal) 실리카로 피복되어 있다. 섬아연석과 섬유아연석으로 구성되어 있는 아연이 풍부한 황화물의 FeS 함량은 13.9~34.3 mole%의 범위를 보이며, 철이 풍부한 중심부와 철이 부족한 연변부를 지닌다. 이는 광화유체의 화학적.물리석 특성들의 변화로부터 기인되었으리라 사료된다. 침니 내부성장대별 화학조성은 열적구배 및 구성광물의 차이로 인해 다른 특징들을 보여주고 있다. 광화후기에 침전된 비정질 실리카중의 액상이 풍부한 유체포유물을 대상으로 가열 및 냉각 실험을 수행한 결과, 열수유체의 최소 포획 온도는 약 114$^{\circ}$~145$^{\circ}C$이며, 해당 염농도는 3.2~4.8 wt.% NaCl equip, 이다. 실제 열구에서 배출되는 유체 온도 자료를 입수하지는 못했지만, 본 연구를 통해서 광물의 침전작용 동안 상대적으로 저온의 침전조건이 매우 지배적이었음을 알수 있다. Juan de Fuca 해령내 Cleft seamen에서 회수된 황화물 침니는 산출형태, 교질성 조직, 전(bulk) 화학조성, 광물조합(황철석+백철석+섬유아연석+비정질 실리카) 등으로 볼 때, 기존 보고된 침니 유형보다는 상당히 낮은 온도에서 느린 유체 유동과 전도성 냉각(<25$0^{\circ}C$)에 의해 생성되었으리라 사료된다.