U-Pb(SHRIMP) and K-Ar Age Dating of Intrusive Rocks and Skarn Minerals at the W-Skarn in Weondong Deposit

원동 중석 스카른대에서의 관입암류와 스카른광물에 대한 U-Pb(SHRIMP) 및 K-Ar 연대

  • Received : 2013.08.26
  • Accepted : 2013.09.27
  • Published : 2013.09.30


The geology of the weondong deposit area consists mainly of Cambro-Ordovician and Carboniferous-Triassic formations, and intruded quartz porphyry and dyke. The skarn mineralized zone in the weondong deposit is the most prospective region for the useful W-mineral deposits. To determine the skarn-mineralization age, U-Pb SHRIMP and K-Ar age dating methods were employed. The U-Pb zircon ages of quartz porphyry intrusion (WD-A) and feldspar porphyry dyke (WD-B) are 79.37 Ma and 50.64 Ma. The K-Ar ages of coarse-grained crystalline phlogopite (WD-1), massive phlogopite (WDR-1), phlogopite coexisted with skarn minerals (WD-M), and vein type illite (WD-2) were determined as $49.1{\pm}1.1$ Ma, $49.2{\pm}1.2$ Ma, $49.9{\pm}3.6$ Ma, and $48.3{\pm}1.1$ Ma, respectively. And the ages of the high uranium zircon of hydrothermally altered quartz porphyry (WD-C) range from 59.7 to 38.7 Ma, which dependson zircon's textures affected by hydrothermal fluids. It is regarded as the effect of some hydrothermal events, which may precipitate and overgrow the high-U zircons, and happen the zircon's metamictization and dissolution-reprecipitation reactions. Based on the K-Ar age datings for the skarn minerals and field evidences, we suggest that the timing of W-skarn mineralization in weondong deposit may be about 50 Ma. However, for the accurate timing of skarn mineralization in this area, the additional researches about the sequence of superposition at the skarn minerals and geological relationship between skarn deposits and dyke should be needed in the future.


Weondong deposit;zircon U-Pb (SHRIMP) age dating;K-Ar age dating;high Uranium zircon;zircon metamictization texture;zircon dissolution-reprecipitation texture


  1. Ahrens, L.H. (1965). Some observations on the uranium and thorium distributions in accessory zircon from granitic rocks. Geochimica et Cosmochimica Acta, 29, 711-716.
  2. Chi, S.J., Kang, I.-M., Kim, Y.U., Kim, E.-J., Kim, I.J., Park, S,-W., Lee, J.H., Lee, J.S., Lee, H.Y., Jin, K., Heo, C.-H., and Hong, Y.-K. (2011) Evaluation of development possibility for the security of industrial mineral resources (Cu, Pb, Zn, Au etc) on the domestic mines: Korea Institute Geoscience and Mineral Resources, GP2010-024-2011(2), 33-135.
  3. Cho, D.L. and Kwon, S.T. (1994) Hornblende geobarometry of the Mesozoic granitoids in South Korea and the evolution of crustal thickness. Journal of the Geological Society of Korea, 30, 41-61.
  4. Choi, S.-G., Ryu, I.-C., Pak, S.J., Wee, S.-M., Kim, C.S., and Park, M.-E. (2005a) Cretaceous epithermal gold–silver mineralization and geodynamic environment, Korea. Ore Geology Reviews, 26, 115-135.
  5. Choi, S.-G., Kwon, S.-T., Ree, J.-H., So, C.-S., and Pak S.J. (2005b) Origin of Mesozoic gold mineralization in South Korea. The Island Arc, 14, 102-114.
  6. Choi, S.-G., Pak, S.J., Kim, S.W., Kim, C.S., and Oh, C.-W. (2006) Mesozoic Gold-Silver Mineralization in South Korea: Metallogenic Provinces Reestimated to the Geodynamic Setting. Economic and Environmental Geology, 39, 567-581.
  7. Choi, S.-G. and Pak, S.J. (2007) The Origin and Evolution of the Mesozoic Ore-forming Fluids in South Korea: Their Genetic Implications. Economic and Environmental Geology, 40, 517-535.
  8. Farrar, E., Clark, A.H., and Kim, O.J. (1978) Age of the Sangdong tungsten deposits, Republic of Korea, and its bearing on metallogeny of the southern Korean Peninsula. Economic Geology, 76, 547-566.
  9. Geisler, T., Rashwan, A.A., Rahn, M., Poller, U., Zwingmann, H., Pidgeon, R.T., Schleicher, H., and Tomaschek, F. (2003) Low-temperature hydrothermal alteration of natural metamict zircons from the Eastern Desert, Egypt. Mineralogical Magazine, 67, 485-508.
  10. Geisler, T., Schaltegger, U., and Tomaschek, F. (2007) Re-equilibration of Zircon in Aqueous Fluids and Melts. Elements, 3, 43-50.
  11. Hanchar, J.M. and Hoskin, P.W.O. (2003). Zircon, 53, 500 p. Reviews in Mineralogy and Geochemistry, Mineralogical Society of America and the Geochemical Society, Chantilly, Virginia.
  12. Hwang, D.H. and Lee, J.Y. (1998) Ore genesis of the Wondong polymetallic mineral deposits in the Taebaegsan Metallogenic Province. Economic and Environmental Geology, 31, 375-388.
  13. Itaya, T., Nagao, K., Inoue, K., Honjou, Y., Okada, T., and Ogata, A. (1991). Argon isotope analysis by a newly developed mass spectrometric system for K-Ar dating. Mineralogical journal, 15, 203-221.
  14. Lee, J.H. (2011) The results of drilling in weondong mine area, the Taebaegsan mineralized district, Republic of Korea. Economic and Environmental Geology, 44, 313-320.
  15. Ludwig, K.R. (2003) User's manual for Isoplot 3.00: a geochronogical toolkit for Mirosoft Excel. Berkeley Geochronology, Center Special Publication, p.47.
  16. Maruyama, S., Isozaki, Y., Kimura, G., and Terabayashi, M. (1997) Paleogeographic maps of the Japanese Islands: Plate tectonic synthesis from 750Ma to the present. Island Arc, 6, 121-142.
  17. Paces, J.B. and Miller, J.D. (1993) Precise U-Pb ages of Duluth Complex and related mafic intrusions, northeastern Minnesota: geochronological insights to physical, petrogenetic, paleomagnetic, and tectonomagmatic processes associated with the 1.1 Ga midcontinent rift system. Journal of Geophysical Research 98, 13997-14013.
  18. Park, H.-I., Chang, H.W., and Jin, M.S. (1988) K-Ar ages of mineral deposits in the Taebaeg Mountain district. The Journal of Korean Institute of Mining Geology, 21, 57-67.
  19. Sato, K., Shibata, K., Uchiumi, S., and Shimazaki, H. (1981) Mineralization age of the Shinyemi Zn-Pb- Mo deposit in the Taebaegsan area, Southern Korea. Mining Geology, 31, 333-336
  20. Shore, M. and Fowler, A.D. (1996). Oscillatory zoning in minerals; a common phenomenon. The Canadian Mineralogist, 34(6), 1111-1126.
  21. Utsunomiya, S., Valley, J.W., Cavosie, A.J., Wilde, S. A., and Ewing, R.C. (2007) Radiation damage and alteration of zircon from a 3.3 Ga porphyritic granite from the Jack Hills, Western Australia. Chemical Geology, 236, 92-111.
  22. Williams, I.S. (1998) U-Th-Pb geochronology by ion microprobe. In: Mickibben, M.A., Shanks III, W.C., Ridley, W.I. (eds.), Applications of Micro Analytical Techniques to Understanding Mineralizing Processes. Reviews of Economic Geology, 7, 1-35.
  23. Xu, X.S., Zhang, M., Zhu, K.Y., Chen, X.M., and He, Z.Y. (2012) Reverse age zonation of zircon formed by metamictisation and hydrothermal fluid leaching. Lithos, 150, 256-267.
  24. Yun S. and Silberman M.L.(1979) K-Ar geochronology of igneous rocks in the Yeonhwa-Ulchin zinc-lead district and southern margin of the Taebaegsan basin, Korea. Journal of the Geological Society of Korea, 15, 89-99.

Cited by

  1. Metasomatic changes during periodic fluid flux recorded in grandite garnet from the Weondong W-skarn deposit, South Korea vol.451, 2017,
  2. Spectral characteristics of minerals associated with skarn deposits: a case study of Weondong skarn deposit, South Korea vol.20, pp.2, 2016,
  3. Skarn zonation and rock physical properties of the Wondong Fe-Pb-Zn polymetallic deposit, Korea vol.19, pp.4, 2015,
  4. Oscillatory zoning in skarn garnet: Implications for tungsten ore exploration vol.89, 2017,
  5. Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea: Record of post-magmatic alteration vol.260, 2016,
  6. Reactivated Timings of Yangsan Fault in the Sangcheon-ri Area, Korea vol.49, pp.2, 2016,


Supported by : 한국지질자원연구원