Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea
Eunjeok Au–Ag deposits are situated in the Yeongam district, Cheollanamdo-province, South Korea. They are genetically related to the Bulgugsa magmatic event (ca. 110–60 Ma), caused by the transition in the subduction direction and style of the Izanagi Plate. Three gold- and silver-bearing hydrotherm...
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MDPI AG
2021-10-01
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| Online Access: | https://www.mdpi.com/2075-163X/11/10/1088 |
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| author | Chul-Ho Heo Seong-Yong Kim Il-Hwan Oh |
| author_facet | Chul-Ho Heo Seong-Yong Kim Il-Hwan Oh |
| author_sort | Chul-Ho Heo |
| collection | DOAJ |
| description | Eunjeok Au–Ag deposits are situated in the Yeongam district, Cheollanamdo-province, South Korea. They are genetically related to the Bulgugsa magmatic event (ca. 110–60 Ma), caused by the transition in the subduction direction and style of the Izanagi Plate. Three gold- and silver-bearing hydrothermal veins filled the fractures of the Cretaceous rhyolitic tuff. The major ore minerals were arsenopyrite (31.47–32.20 at.% As), pyrite, chalcopyrite, sphalerite (8.58–10.71 FeS mole%) and galena with minor amounts of electrum (62.77–78.15 at.% Au), native silver, and argentite. Sericitization was dominant in the alteration zone. The various textures of quartz veins (i.e., breccia, crustiform, comb, and vuggy) may indicate the formation of an epithermal environment. The auriferous fluids with the H<sub>2</sub>O–NaCl system have homogenization temperatures and salinities of 204 °C to 314 °C, less than 10 wt.% equiv. NaCl, and experienced mixing (dilution and cooling) events during mineralization. Considering the characteristics of the geologic setting, major fault system, and host rock, the Eunjeok Au–Ag deposit within the Yeongam district tends to share the general geologic characteristics of Haenam–Jindo epithermal mineralization episodes. However, the age of gold–silver mineralization (86.0 Ma) is older than that of Haenam–Jindo epithermal mineralization episodes (<70.3 Ma), implying some differences exist in the genetic sequence of extensional characteristics caused by transcurrent Gwangju–Yeongdong faults. |
| first_indexed | 2024-03-10T06:21:11Z |
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| language | English |
| last_indexed | 2024-03-10T06:21:11Z |
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| series | Minerals |
| spelling | doaj.art-8103aa42fd9140dba217a5ce34f68f5e2023-11-22T19:16:38ZengMDPI AGMinerals2075-163X2021-10-011110108810.3390/min11101088Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South KoreaChul-Ho Heo0Seong-Yong Kim1Il-Hwan Oh2Mineral Resources Development Research Center, Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, KoreaGeo-Technology Policy Research Center, Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, KoreaMineral Resources Development Research Center, Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, KoreaEunjeok Au–Ag deposits are situated in the Yeongam district, Cheollanamdo-province, South Korea. They are genetically related to the Bulgugsa magmatic event (ca. 110–60 Ma), caused by the transition in the subduction direction and style of the Izanagi Plate. Three gold- and silver-bearing hydrothermal veins filled the fractures of the Cretaceous rhyolitic tuff. The major ore minerals were arsenopyrite (31.47–32.20 at.% As), pyrite, chalcopyrite, sphalerite (8.58–10.71 FeS mole%) and galena with minor amounts of electrum (62.77–78.15 at.% Au), native silver, and argentite. Sericitization was dominant in the alteration zone. The various textures of quartz veins (i.e., breccia, crustiform, comb, and vuggy) may indicate the formation of an epithermal environment. The auriferous fluids with the H<sub>2</sub>O–NaCl system have homogenization temperatures and salinities of 204 °C to 314 °C, less than 10 wt.% equiv. NaCl, and experienced mixing (dilution and cooling) events during mineralization. Considering the characteristics of the geologic setting, major fault system, and host rock, the Eunjeok Au–Ag deposit within the Yeongam district tends to share the general geologic characteristics of Haenam–Jindo epithermal mineralization episodes. However, the age of gold–silver mineralization (86.0 Ma) is older than that of Haenam–Jindo epithermal mineralization episodes (<70.3 Ma), implying some differences exist in the genetic sequence of extensional characteristics caused by transcurrent Gwangju–Yeongdong faults.https://www.mdpi.com/2075-163X/11/10/1088Eunjeok depositepithermal gold–silverLate Cretaceous magmatism |
| spellingShingle | Chul-Ho Heo Seong-Yong Kim Il-Hwan Oh Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea Minerals Eunjeok deposit epithermal gold–silver Late Cretaceous magmatism |
| title | Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea |
| title_full | Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea |
| title_fullStr | Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea |
| title_full_unstemmed | Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea |
| title_short | Genetic Environments of the Eunjeok Au–Ag Deposit in the Yeongam District: Implications for Cretaceous Epithermal Au–Ag Mineralization in South Korea |
| title_sort | genetic environments of the eunjeok au ag deposit in the yeongam district implications for cretaceous epithermal au ag mineralization in south korea |
| topic | Eunjeok deposit epithermal gold–silver Late Cretaceous magmatism |
| url | https://www.mdpi.com/2075-163X/11/10/1088 |
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