Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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Element Dispersion by the Wallrock Alteration of Daehyun Gold-silver Deposit

대현 금-은광상의 모암변질에 따른 원소분산

  • Yoo, Bong Chul (Mineral Resources Research Department, Korea Institute of Geoscience and Mineral Resources)
  • 유봉철 (한국지질자원연구원 광물자원연구실)
  • Received : 2013.03.24
  • Accepted : 2013.04.09
  • Published : 2013.04.28
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Abstract

The Daehyun gold-silver deposit consists of two hydrothermal quartz veins that fill NE-trending fractures in the Cambro-Ordovician calcitic marble. I have sampled wallrock, hydrothermaly-altered rock and gold-silver ore vein to study the element dispersion and element gain/loss during wallrock alteration. The hydrothermal alteration doesn't remarkably recognized at this deposit and consists of mainly calcite, dolomite, quartz and minor epidote. The ore minerals composed of arsenopyrite, pyrrhotite, pyrite, sphalerite, stannite, chalcopyrite, galena, electrum, native bismuth and silver-bearing mineral. Based on analyzed data, the chemical composition of wallrock consists of mainly $SiO_2$, CaO, $CO_2$ with amounts of $Al_2O_3$, $Fe_2O_3(T)$ and MgO. The contents of $SiO_2$, $Fe_2O_3(T)$, MgO, CaO and $CO_2$ vary significantly with distance from ore vein. The element dispersion doesn't remarkably recognized during wallrock alteration and only occurs near the ore vein margin because of physical and chemical properties of wallrock. Remarkable gain elements during wallrock alteration are $Fe_2O_3(T)$, total S, Ag, As, Bi, Cd, Cu, Ni, Pb, Sb, Sn, W and Zn. Remarkable loss elements are $SiO_2$, MnO, MgO, CaO. $CO_2$ and Sr. Therefore, Our result may be used when geochemical exploration carry out at deposits hosted calcitic marble in the Hwanggangri metallogenic district.

대현 금-은광상은 Cambro-Ordovician 석회암질 대리암내에 발달된 NE 방향성의 단열대를 따라 형성된 2개의 열수성 석영맥으로 구성된다. 모암변질시 원소 분산과 이득/손실을 알아보기 위해 모암, 열수변질대 및 금-은 광맥에서 시료를 채취하였다. 모암변질시 뚜렷한 변질대가 관찰되지 않으며 구성광물은 주로 방해석, 돌로마이트, 석영과 소량 녹염석 등이다. 이 광상의 광석광물은 유비철석, 자류철석, 황철석, 섬아연석, 황석석, 황동석, 방연석, 에렉트럼, 자연 창연 및 은 광물 등이 산출된다. 분석된 자료를 기초로, 모암은 주로 $SiO_2$, CaO 및 $CO_2$로 구성되며 소량 $Al_2O_3$, $Fe_2O_3(T)$ 및 MgO 등이 함유되어 있다. 광체로부터 모암으로 감에 따라 $SiO_2$, $Fe_2O_3(T)$, MgO, CaO 및 $CO_2$ 함량은 변화 폭이 크게 관찰된다. 모암변질시 모암의 물리-화학적 물성 때문에 원소 분산은 현저히 관찰되지 않으며 단지 광체 주변부에서만 관찰된다. 모암변질시 이득원소들은 $Fe_2O_3(T)$, 총 S, Ag, As, Bi, Cd, Cu, Ni, Pb, Sb, Sn, W 및 Zn이고 손실원소들은 $SiO_2$, MnO, MgO, CaO. $CO_2$ 및 Sr 이다. 따라서 우리의 결과물은 황강리 광화대내 석회암질 대리암을 모암으로 갖는 광상들의 지화학탐사시 활용될 수 있을 것이다.

Keywords

References

  1. Chang, H.W. and Lee, K.S. (1991) Behavior of elements in hydrothermal alteration zones of granitic rocks : Examples from the Mugeug granodiorite and the Naeduckri granite, South Korea. Journal of Geological Society of Korea, v.27, p.156-170.
  2. Cho, D.L. and Kwon, S.T. (1994) Hornblede geobarometry of the Mesozoic granitoids and the evolution of crustal thickness. Journal of Geological Society of Korea, v.30, p.41-61.
  3. Grant, J.A. (1986) The isocon diagram-A simple solution to Gresens' equation for metasomatic alteration. Economic Geology, v.81, p.1976-1982. https://doi.org/10.2113/gsecongeo.81.8.1976
  4. Gresens, R.L. (1967) Composition-volume relationships of metasomatism. Chemical Geology, v.2, p.47-65. https://doi.org/10.1016/0009-2541(67)90004-6
  5. Hofmann, A. (1972) Chromatographic theory of infiltration metasomatism and its application to feldspar. American Journal of Sciences, v.272, p.69-90.
  6. Hwang, I.H. and Chon, H.T. (1994a) Wallrock alteration and primary dispersion of elements in the vicinity of the Mugeug gold-bearing quartz veins. Economic and Environmental Geology, v.27, p.387-396.
  7. Hwang, I.H. and Chon, H.T. (1994b) Primary dispersion of elements in altered wallrocks around the gold-bearing quartz veins the Okgye mine. Economic and Environmental Geology, v.27, p.549-556.
  8. Ishihara, S., Jin, M.S. and Terashima, S. (2005) Morelated adakitic granitoids from non-island-arc setting: Jecheon pluton of South Korea. Resource Geology, v.55, p.385-396. https://doi.org/10.1111/j.1751-3928.2005.tb00259.x
  9. Korea Mining Promotion Corporation (2006) Detailed survey report (Au-Ag-Cu-Pb-Zn: Jecheon area), 114p.
  10. Korea Mining Promotion Corporation (1987) Deposits of the Korea, p.172-173.
  11. Maclean, W.H. and Barrett, T.J. (1993) Lithogeochemical techniques using immobile elements. Journal of Geochemical Exploration, v.48, p.109-133. https://doi.org/10.1016/0375-6742(93)90002-4
  12. Maclean, W.H. and Kranidiotis, P. (1987) Immobile elements as monitors of mass transfer in hydrothermal alteration: Phelps Dodge massive sulfide deposit, Matagami, Quebec. Economic Geology, v.82, p.951- 962. https://doi.org/10.2113/gsecongeo.82.4.951
  13. Moon, S.H. and Park, H.I. (1994) Alterations of granite gneiss and their genetic relationship to tin mineralization in the Uljin area. Journal of Geological Society of Korea, v.30, p.125-139.
  14. Oh, D.G. and Chon, H.T. (1993) Geochemical dispersion of elements in volcanic wallrocks of pyrophyllite deposits in Milyang area, Kyeongnam province. Mining Geology, v.26, p.337-347.
  15. Reedman, H.H., Fletcher, C.J.N., Evans, R.B., Workman, D.R., Yoon, K.S., Rhyu, H.S., Jeong, S.W. and Park, J.N. (1973) Geological, geophysical and geochemical investigations in the Hwanggangri area Chungchong pukdo. Anglo-Korean Mineral Exploration Group, 118p.
  16. Shin, D.B. and Lee, I.S. (2003) Carbonate-hosted talc deposits in the contact aureole of an igneous intrusion (Hwanggangri mineralized zone, South Korea): geochemistry, phase relationships, and stable isotope studies. Ore Geology Reviews, v.22, p.17-39. https://doi.org/10.1016/S0169-1368(02)00085-9
  17. So, C.S. and Yun, S.T. (1992) Geochemistry and genesis of hydrothermal Au-Ag-Pb-Zn deposits in the Hwanggangri mineralized district, Republic of Korea. Economic Geology, v.87, p.2056-2084. https://doi.org/10.2113/gsecongeo.87.8.2056
  18. Yoo, B.C. (2012) Element dispersion by the wallrock alteration of Janggun Lead-Zinc-Silver deposit. Economic and Environmental Geology, v.45, p.623-641. https://doi.org/10.9719/EEG.2012.45.6.623
  19. Yoo, B.C., Chi, S.J., Lee, G.J., Lee, J.K. and Lee, H.K. (2007) Element dispersion and wall-rock alteration from Daebong gold-silver deposit, Republic of Korea. Economic and Environmental Geology, v.40, p.713- 726.
  20. Yoo, B.C., Lee, G.J., Lee, J.K., Ji, E.K. and Lee, H.K. (2009) Element dispersion and wallrock alteration from Samgwang deposit. Economic and Environmental Geology, v.42, p.177-193.
  21. Yoo, B.C., Brown, P.E. and White, N.C. (2011) Magmatichydrothermal fluid characteristics and genesis of Cu quartz veins in the Hwanggangri metallogenic distrit, Republic of Korea: Mineralogy, fluid inclusion and stable isotope studies. Journal of Geochemical Exploration, v.110, p.245-259. https://doi.org/10.1016/j.gexplo.2011.05.012
  22. Yoon, C.H. (1993) Gold abundance in acid-sulfate alteration zone of the Ogmaesan-Seongsan ore deposits in Haenam area, Korea. Mining Geology, v.26, p.155-166.