Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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Ore Minerals, Fluid Inclusion and Stable Isotope Studies of the Bongsang Gold-silver Deposit, Republic of Korea

봉상 금-은광상의 광석광물, 유체포유물 및 안정동위원소 연구

  • Yoo, Bong-Chul (Department of geology and environmental sciences, Chungnam National University) ;
  • Lee, Jong-Kil (Department of geology and environmental sciences, Chungnam National University) ;
  • Lee, Gil-Jae (Department of geology and environmental sciences, Chungnam National University) ;
  • Lee, Hyun-Koo (Department of geology and environmental sciences, Chungnam National University)
  • 유봉철 (충남대학교 지구환경과학과) ;
  • 이종길 (충남대학교 지구환경과학과) ;
  • 이길재 (충남대학교 지구환경과학과) ;
  • 이현구 (충남대학교 지구환경과학과)
  • Published : 2008.02.28
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Abstract

The Bongsang gold-silver deposit consists of quartz veins that fill along the fault Bone within Cretaceous andesitic lapilli tuff. Mineralization is occurred within fault-breccia zones and can be divided into two stages. Stage I which can be subdivided into early and late depositional stages is main ore mineralization and stage II is barren. Stage I began with deposition of wall-rock alteration minerals and base-metal sulfides, and was deposited by later native silver, Ag-bearing tetrahedrite, polybasite and base-metal sulfides such like pyrite, sphalerite, chalcopyrite and galena. Fluid inclusion data indicate that homogenization temperatures and salinities of stage I range from 137 to $336^{\circ}C$ and from 0.0 to 10.6 wt.% NaCl, respectively. It suggests that ore forming fluids were cooled and diluted with the mixing of meteoric water. Also, temperature and sulfur fugacity deduced mineral assemblages of late stage I are $<210^{\circ}C\;and\;<10^{-15.4}$ atm, respectively. Sulfur(3.4%o) isotope composition indicates that ore sulfur was mainly derived from a magmatic source as well as the host rocks. The calculated oxygen{2.9%o, 10.3%o(quartz: 7.9%o, 8.9%o, calcite: 2.9%o, 10.3%o)}, hydrogen(-75%o) and carbon(-7.0%o, -5.9%o) isotope compositions indicate that hydrothermal fluids may be meteoric origin with some degree of mixing of another meteoric water for paragenetic time.

봉상 금-은광상은 백악기 안산암질 래필리응회암 내에 발달된 단층대를 충진한 석영맥광상이다. 이 광상의 광화작용은 단층-각력대에 수반되며 2시기로 구분된다. 1시기는 다시 조기와 말기로 구분되며 주된 광화시기이다. II시기는 광화작용이 관찰되지 않는다. I시기 조기는 모암변질과 천금속 황화광물이 관찰된다. I시기 말기는 금-은광물 정출시기로 자연은, 함은사면동석 및 휘안동은석과 함께 황철석, 섬아연석, 황동석 및 방연석 등의 황화광물이 관찰된다. 유체포유물 자료에 의하면, 광화I시기의 균일화온도와 염농도는 각각 $137{\sim}336^{\circ}C,\;0.0{\sim}10.6wt.%$ NaCl 로서 광화유체가 천수의 혼입에 의한 냉각과 희석이 있었음을 지시한다. 또한, 광화I시기 말기에 관찰되는 광물공생군으로부터 구한 생성온도와 황분압은 $<210^{\circ}C$과 $<10^{-15.4}$ atm를 갖는다. 황(3.4%o 기원은 화성기원과 모암내의 황에서 유래된 것으로 해석된다. 산소{2.9%o과 10.3%o(석영: 7.9%o과 8.9%o, 방해석: 2.9%o과 10.3%o)}, 수소(-75%o) 및 탄소(-7.0%o과 -5.9%o)동위원소값의 자료로 볼 때, 이 광상의 광화유체는 천수 기원의 유체가 주종을 이룬 것으로 보이며 광화작용이 진행됨에 따라 기원이 다른 천수의 혼입이 작용한 것으로 해석할 수 있다.

Keywords

References

  1. Barret, T.J. and Anderson, G.M. (1988) The solubility of sphalerite and galena in 1-5 m NaCl solutions to $300^{\circ}C$. Geochim. Cosmochim. Acta., v. 52, p. 813-820 https://doi.org/10.1016/0016-7037(88)90353-5
  2. Bodnar, R.J. (1983) A method of calculating fluid inclusion volumes based on vapor bubble diameters and P-V-TX properties of inclusion fluids. Econ. Geol., v. 78, p. 535-542 https://doi.org/10.2113/gsecongeo.78.3.535
  3. Bodnar, R.J. and Vityk, M.O. (1994) Interpretation of microthermometric data for $H_2O$-NaCl fluid inclusion In De Vivo, B. and Frezzotti, M.L (eds.) Fluid inclusions in minerals: Method and applications, Short Course International Mineralogical Assoc., p. 117-130
  4. Chang, T.W., Hwang, S.K., Lee, D.W., Oh, I.S., Kim, H.C. and Kim, E.H. (1983) Geological map of Chungmu sheet. Korea Inst. Energy and Resources, 18p
  5. Choi, S.H., So, C.S. and Lee, J.H. (1993) Mineralogical, stable isotope and fluid inclusion studies of copperbearing hydrothermal vein deposits in Goseong mining district, Gyeongsang basin, Korea, Min. Soc., v. 102, p. 123-133
  6. Friedman, I. and O'Neil, J. R. (1977) Compilation of stable isotope fractionation factors of geochemical interest. In Fleisher, M., (ed.) Data of geochemistry, Sixth Edition, U. S. Geol. Survey Prof. Paper 440-KK, p. KK1- KK12
  7. Gammons, C.H. and Williams-Jones, A.E. (1995) The solubility of Au-Ag alloy+AgCl in HCl/NaCl solutions at $300^{\circ}C$: New data on the stability of Au(I) chloride complexes in hydrothermal fluids. Geochim. Cosmochim. Acta., v. 59, p. 3453-3468 https://doi.org/10.1016/0016-7037(95)00234-Q
  8. Hackbarth, C.J. and Petersen, U. (1984) Systematic compositional variations in argentian tetrahedrite. Econ. Geol., v. 79, p. 448-460 https://doi.org/10.2113/gsecongeo.79.3.448
  9. Hall, D.L. Sterner, S.M. and Bodnar, R.J. (1988) Freezing point depression of NaCl-KCl-$H_2O$ solutions. Econ. Geol., v. 83, p. 197-202 https://doi.org/10.2113/gsecongeo.83.1.197
  10. Ixer, R.A. Pattrick, R.A.D. and Starkey, R.E. (1993) Leadzinc- copper-arsenic-baryte mineralization from Clevedon, near Bristol. Jour. Russell Soc., v. 5, p. 23-30
  11. Jaw, Y.J. (1998) Petrology of the igneous rocks in the Goseong area, Gyeongsang basin II. Trace element geochemistry and Rb-Sr radiometric age. Econ. Environ. Geol., v. 31, p. 473-483
  12. Kim, C.J. and Park, H.I. (1984) Mineral paragenesis and fluid inclusions of Geoje copper ore deposits. J. Korean Inst. Mining Geol., v. 17, p. 245-258
  13. Kim, K.H. and Nakai, N. (1988) Isotopic compositions of precipitations and groundwaters in South Korea. Jour. Geol. Soc. Korea, v. 24, p. 37-46
  14. Korea Mining Promotion Corporation (1975) Survey report of Bongsang mine. 14p
  15. Korea Mining Promotion Corporation (1977) Drilling survey report of ore deposits. p. 738-739
  16. Korea Mining Promotion Corporation (1987) Drilling survey report of ore deposits. p. 930-931
  17. Kubo, T., Nakato, T. and Uchida, E. (1992) An experimental study on partitioning of Zn, Fe, Mn and Cd between sphalerite and aqueous chloride solution. Mining Geol., v. 42, p. 301-309
  18. Lee, C.H. (1993) Geology, mineralogy, fluid inclusion and stable isotope of gold, silver and antimony ore deposits of the Dunjeon-Baegjon area, northern Taebaegsan mning district, Korea. Unpub. Ph.D. thesis. Seoul Nat. Univ., 422p
  19. Lee, J.H. (1992) Hydrothermal copper mineralization in the Goseong district, Korea. Unpub. Ph.D. thesis. Korea Univ., 117p
  20. Lee, H.K., Yoo, B.C., Jeong, K.Y. and Kim, K.H. (1994) Au-Ag minerals and geneses of Weolyu gold-silver deposits, Chungcheongbukdo, Republic of Korea. Econ. Environ. Geol., v. 27, p. 537-548
  21. Lee, H.K., Yoo, B.C. and Kim, S.J. (1992) Mineralogy and ore geneses of the Daebong gold-silver deposits, Chungnam, Korea. J. Korean Inst. Mining Geol., v. 25, p. 297-316
  22. Lee, H.K., Yoo, B.C. and Kim, S.J. (1995) Au-Ag minerals and genetic environments from the Yeongdeog goldsilver deposits, Korea. Econ. Environ. Geol., v. 28, p. 541-551
  23. Lee, S.Y., Choi, S.G., So, C.S., Ryu, I.C., Wee, S.M. and Heo, C.H. (2003) Base-metal mineralization in the Cretaceous Gyeongsang basin and its genetic implications, Korea: the Haman-Gunbug-Goseong(-Changwon) and the Euiseong metallogenic provinces. Econ. Environ. Geol., v. 36, p. 257-268
  24. Linke, W.F. (1965) Solubilities of inorganic and metalorganic compounds. 4th ed., Washington, D.C., Am. Chem. Soc., 1914p
  25. Lueth, V.W., Megaw, P.K.M., Pingitore, N.E. and Goodell, P.C. (2000) Systematic variation in galena solid-solution compositions at Santa Eulalia, Chihuahua, Mexico. Econ. Geol., v. 95, p. 1673-1687 https://doi.org/10.2113/95.8.1673
  26. Luzhnaya, N.P. and Vereshtchetina, I.P. (1946) Sodium, calcium, magnesium chlorides in aqueous solutions at -57 to $+25^{\circ}C$(polythermal solubility). Zhurnl. Prikl. Khimii., v. 19, p. 723-733
  27. Matsuhisa, Y., Goldsmith, R. and Clayton, R.N. (1979) Oxygen isotope fractionation in the system quartzalbite- anorthite-water. Geochim. Cosmochim. Acta., v. 43, p. 1131-1140 https://doi.org/10.1016/0016-7037(79)90099-1
  28. Ohmoto, H. (1986) Stable isotope geochemistry of ore deposits. Reviews in Min., v. 16, p. 491-560
  29. Ohmoto, H. and Rye, R.O. (1979) Isotopes of sulfur and carbon. In Barnes, H. L., (ed.) Geochemistry of Hydrothermal Ore Deposits. New York, John Wiley and Sons, p. 509-567
  30. Park, H.I. (1983) Ore and fluid inclusions of the Tongyeong gold-silver deposits. J. Korean Inst. Mining Geol., v. 16, p. 245-251
  31. Park, H.I., Choi, S.W., Chang, H.W. and Lee, M.S. (1983) Genesis of the copper deposits in Goseong district, Gyeongnam area. J. Korean Inst. Mining Geol., v. 16, p. 135-147
  32. Park, H.I., Woo, Y.K. and Hwang, J. (1988) Polymetallic mineralization in the Eunchi silver mine. Jour. Geol. Soc. Korea, v. 24, p. 431-449
  33. Park, H.I. and Hwang, J. (1992) Chemical compositions of tetrahedrite-series minerals from Eunchi and Jungbong silver deposits. Jour. Geol. Soc. Korea, v. 28, p. 615-626
  34. Pattrick, R.A.D. (1978) Microprobe analyses of cadmiumrich tetrahedrites from Tyndrum, Perthshire, Scotland. Min. Mag., v. 42, p. 286-288 https://doi.org/10.1180/minmag.1978.042.322.25
  35. Pattrick, R.A.D. (1984) Sulphide mineralogy of the Tomnadashan copper deposit and the Corrie Buie lead veins, south Loch Tayside, Scotland. Min. Mag., v. 48, p. 85-91 https://doi.org/10.1180/minmag.1984.048.346.11
  36. Pattrick, R.A.D. (1985) Pb-Zn and minor U mineralization at Tyndrum, Scotland. Min. Mag., v. 49, p. 671-681 https://doi.org/10.1180/minmag.1985.049.354.06
  37. Pattrick, R.A.D. and Hall, A.J. (1983) Silver substitution into synthetic zinc, cadmium and iron tetrahedrites. Min. Mag., v. 47, p. 441-451 https://doi.org/10.1180/minmag.1983.047.345.05
  38. Richards, J. and Kerrich, R. (2007) Adakite-like rocks: Their diverse origins and questionable role in metallogenesis. Econ. Geol., v. 102, p. 537-576 https://doi.org/10.2113/gsecongeo.102.4.537
  39. Robinson, R.W. and Norman, D.I. (1984) Mineralogy and fluid inclusion study of the southern amethyst vein system, Creede mining district, Colorado. Econ. Geol., v. 79, p. 439-447 https://doi.org/10.2113/gsecongeo.79.3.439
  40. Shelton, K.L., So, C.S., Haeussler, G.T., Chi, S.J. and Lee, K.Y. (1990) Geochemical studies of the Tongyoung gold-silver deposits, Republic of Korea; Evidence of meteoric water dominance in a Te-bearing epithermal system. Econ. Geol., v. 85, p. 1114-1132 https://doi.org/10.2113/gsecongeo.85.6.1114
  41. Sheppard, S.M.F. (1986) Characterization and isotope variations in natural waters. Reviews in Min., v. 16, p. 165-183
  42. Sterner, S.M., Hall, D.L. and Bodnar, R.J. (1988) Synthetic fluid inclusions. V. Solubility relations in the system NaCl-KCl-$H_2O$ under vapor-saturated conditions. Geochim. Cosmochim. Acta., v. 52, p. 989-1005 https://doi.org/10.1016/0016-7037(88)90254-2
  43. Yoo, B.C., Lee, H.K. and Kim, K.J. (2006) Ore minerals and genetic environments from the Baekun gold-silver deposit, Republic of Korea. Econ. Environ. Geol., v. 39, p. 9-25