The Journal of the Petrological Society of Korea (암석학회지)

The Petrological Society of Korea (한국암석학회)
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Petrological Study on Small-scale Granites in the Central Part of Yeongnam Massif

영남육괴 중부지방에 존재하는 소규모 화강암체들의 암석학적 연구

  • Kim, Hyeong-Gyu (Department of Geology and Research Institute of Natural Sciences, Gyeongsang National University) ;
  • Jwa, Yong-Joo (Department of Geology and Research Institute of Natural Sciences, Gyeongsang National University) ;
  • Kim, Jae-Hwan (National Research Institute of Cultural Heritage, Cultural Heritage Administration) ;
  • Park, Sung-Chul (National Research Institute of Cultural Heritage, Cultural Heritage Administration)
  • 김형규 (경상대학교 지질과학과 및 기초과학연구소) ;
  • 좌용주 (경상대학교 지질과학과 및 기초과학연구소) ;
  • 김재환 (문화재청 국립문화재연구소) ;
  • 박성철 (문화재청 국립문화재연구소)
  • Received : 2019.11.25
  • Accepted : 2019.12.16
  • Published : 2019.12.31
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Abstract

Mupung granite, which is located adjacent to Gimcheon granites to the north and Geochang granites to the south, has been known to consist of biotite-hornblende granite (Gbh), porphyritic granite (Gp), and hornblende-biotite granite (Ghb). In this study, we subdivided the Gbh of Mupung granite into biotite granite (Gb) and biotite hornblende granite (Gbh), based on petrological observations. The grayish Gb with medium to coarse grain and porphyritic texture contains a small amount of muscovite, but the hornblende and mafic microgranular enclave (MME) is not observed in Gb. On the other hand, MME can be commonly found in pinkish Gbh. The mafic minerals in Gbh are mostly hornblende and biotite. In the Gb in Mupung granites, the hornblende and sphene (which is the characteristic minerals in Gimcheon granite) are not observed. In addition, the trend of the changes in major elements of Gb in Mupung granites is similar to that of Geochang granites. These petrological characteristics suggest that the Gb in Mupung granite has a similarity with Geochang granite (than Gimchen granite). We also observed that the texture and composition of minerals of Gbh, as well as those of surrounding Gp and Ghb, are consistent with the characteristics of Cretaceous granites in Gyeongsang basin, rather than those of Jurassic granites in Yeongnam massif.

무풍 화강암체는 북쪽으로는 김천 화강암체와, 남쪽으로는 거창 화강암체와 인접하고 있으며, 흑운모각섬석 화강암(Gbh), 반상화강암(Gp), 각섬석 흑운모 화강암(Ghb)으로 구성되어 있다고 알려져 있다. 이 연구에서, 우리는 암석학적 관찰 결과를 토대로 무풍 화강암체 내 Gbh를 흑운모 화강암(Gb)와 흑운모 각섬석 화강암(Gbh)으로 세분하였다. Gb는 회백색의 암색을 띠며, 중조립질의 반상 조직을 가진다. Gb는 마그마 기원으로 추정되는 소량의 백운모를 포함하고 있으나, 각섬석 및 염기성 미립 포유암(MME)가 관찰되지 않는다. 반면, 홍색 내지 담홍색의 Gbh에서는 MME가 흔히 발견된다. Gbh 내 유색 광물은 대부분 각섬석과 흑운모로 관찰된다. 무풍 화강암체 내 Gb에서는 김천 화강암체의 특징적 광물인 각섬석과 스핀이 관찰되지 않으며, Gb의 주성분 원소의 변화 경향이 김천 화강암체 보다는 거창 화강암체와 비슷한 것으로 보아, Gb의 경우 거창 화강암체와 유사성이 크다는 것을 알 수 있다. 또한, 무풍 화강암체 내 Gbh의 조직과 광물 구성은 주변의 Gp 및 Ghb와 유사하며, 이러한 암석학적 특징은 영남육괴 내 중생대 쥐라기 화강암류 보다는 경상분지 내 백악기 화강암들과 유사하다.

Keywords

References

  1. Chappell, B.W., 1999, Aluminium saturation in I-and S-type granites and the characterization of fractionated haplogranites. Lithos, 46(3), 535-551 https://doi.org/10.1016/S0024-4937(98)00086-3
  2. Cheong, C.-S., Kwon. S.-T. and Park, K.-H., 2000, Pb and Nd isotopic constraints on Paleoproterozoic crustal evolution of the northeastern Yeongnam massif, South Korea. Precambrian Research, 102, 207-220. https://doi.org/10.1016/S0301-9268(00)00066-8
  3. Cho, D.-L., 1992, Mineralogical and lithochemical studies on the origin of Phanerozoic granitic rocks in South Korea, Unpublished Ph.D. dissertation, Yonsei University. 189p.
  4. 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, 41-60.
  5. Choi, J.B., Jwa, Y.-J., Kim, K.-K. and Hwang, G.-C., 2006, Analyses of Mineral Composition of Geochang granitic rocks for stone specification. Journal of Mineralogical Society of Korea, 19, 363-381.
  6. Chough, S.K., Kwon, S.-T., Ree, J.-H. and Choi, D.K., 2000, Earth-Science Reviews, 52(1-3), 175-235 https://doi.org/10.1016/S0012-8252(00)00029-5
  7. Hwang, J.H. and Kihm, Y.H., 2005, Geological report of The Ganghwa.Onsuri sheet. Korea Institite of Geoscience and Mineral Resources, 46p.
  8. Hine, R., Williams, I.S., Chappell, B.W. and White, A.J.R., 1978, Contrasts Between I- and S-Type granitoids of the Kosciusco Batholith. Journal of Geological Society of Australia, 25, 219-234. https://doi.org/10.1080/00167617808729029
  9. Irvine, T.N. and Baragar, W.R.A., 1971, A Guide to the Chemical Classification of the Common Volcanic Rocks. Canadian Journal of Earth Science, 8, 523-548. https://doi.org/10.1139/e71-055
  10. Lee, H.-S., 2010, Magmatic and Metamorphic Events from the Early Triassic to the Early Jurassic in the Central Yeongnam Massif, South Korea and their tectoic implications. Ph.D. dissertation, Pukyong national university, 273p
  11. Lee, S.R. and Cho, K.O., 2012, Precambrian crustal evolution of the Korean Peninsula. Journal of Petrological Society of Koera, 21, 89-112. https://doi.org/10.7854/JPSK.2012.21.2.089
  12. Lee, Y.I., Choi, T.J., Lim, H.S. and Yuji Orihashi., 2010, Detrital zircon geochronology of the Cretaceous Sindong Group, Southeast Korea: Implications for depositional age and Early Cretaceous igneous activity. Island Arc, 19, 647-658. https://doi.org/10.1111/j.1440-1738.2010.00717.x
  13. Jwa, Y.-J. and Park, J.-M., 1996, Petrology of the igneous rocks in the Goseong area, Gyeongsang basin. I. Major element geochemistry and K-Ar radiometric age. Economic and Environmental Geology, 29, 561-573.
  14. Jwa, Y.-J., 2002, Geochemistry of Cretaceous granites in South Korea: The implications for tectonically controlled granitic magmatism. In Mesozoic sedimentation, igneous activity and mineralization in South Korea (ed. Jin et al.), KIGAM, 1, 157-166
  15. Jwa, Y.-J., 2004, Possible source rocks of Mesozoic granites in South Korea: Implications for crustal evolution in NE Asia. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 95, 181-198. https://doi.org/10.1017/S0263593304000161
  16. Jwa, Y.-J., Yuji Orihashi, Kim, H.-G. and Sung, K.-H., 2008, Zircon U-Pb ages of the Mesozoic granites in the central Yeongnam Massif: Including newly found Cretaceous granites. 63th annual meeting of the Geological Socity of Korea (Abstract), Daejeon Convention Center, Oct. 23-24, p.14.
  17. Kee, W.S., Kim, S.W., Jeong, Y.-J. and Kwon S.-H, 2010, Characteristics of Jurassic Continental Arc Magmatism in South Korea: Tectonic Implications: Journal of Geology, 118, 305-323. https://doi.org/10.1086/651503
  18. Kim, J.-S., 2001, Petrology of enclaves from the granitoids in the southern Gyeongsang Basin: Emphasis on magma mingling. Unpublished Ph.D. dissertation, Pusan National University, 210p
  19. Kim, J.-S., Kim, K.-K., Jwa, Y.-J. and Son, M., 2012, Cretaceous to Early Tertiary Granites and Magma Mixing in South Korea: Their Spatio-temporal Variations and Tectonic Implications (Multiple Slab Window Model), Journal of the Geological Society of Korea, 21, 203-216.
  20. Kim, N.-J. and Kim, J.-H., 1970, Explanatory text of the geologic map of Geochang sheet (1:50,000), Geological Survey of Korea, 14p.
  21. Kim, Y.-J., Park, Y.-S., Choo, S.-H. and Oh, M.-S., 1989, The study on the Igneous Activity in the Southeastern Zone of the Ogcheon Geosynclinal Belt, Korea(I) with the Igneous Activity in Namweon-Geochang-Sangju Area. Journal of the Korean Institute of Mining Geology, 4, 355-370.
  22. Kwon, S.-T., Cho, D.-L., Lan, C.Y., Shin, K.B., Lee, T., Mertzman, S.A., 1994, Petrology and geochemistry of the Seoul granitic batholith. Journal of Petrological Society of Korea. 6, 109-127.
  23. Kwon, S.-T. and Ree, J.H., 1997, A note on the age of the Honam Shear Zone. Journal of the Geological Society of Korea, 33, 183-188.
  24. Le Maitre, R.W., 1976, The chemical variability of some common igneous rocks, Jour. Petro., 17, 589-637. https://doi.org/10.1093/petrology/17.4.589
  25. Miller, C.F., Stoddard, E.F., Bradfish, L.J. and Dollase, W.A., 1981, Compositon of plutonic muscovite: genetic implications. Canadian Mineralogist, 19, 25-34.
  26. Park, B.-S. and Lee, Y.-J., 1969, Explanatory text of the geologic map of Mupung sheet (1:50,000), Geological Survey of Korea, 26p.
  27. Park, K.-H., Lee, H.-S., Song, Y.-S. and Cheong, C.-S., 2006, Sphene U-Pb ages of the granite-granodiorites from Hamyang, Geochang and Yeongju areas of the Yeongnam massif. Journal of Petrological Society of Korea, 15, 39-48.
  28. Park, K.-H., 2012, Cyclic igneous activities during the Late Paleozoic to Early Cenozoic period over the Korean peninsula. Journal of Petrological Society of Korea, 21, 193-202. https://doi.org/10.7854/JPSK.2012.21.2.193
  29. Park, Y.-S., Kim, Y.-J., Kwon, S.-T. and Park, J.-B., 1993, Rb-Sr isotopic study on igneous rocks form the Geochang-Koryong area. Journal of the Korean Earth Science Society, 14, 32-43.
  30. Sagong, H., Kwon, S.-T. and Ree, J.-H., 2005, Mesozoic episodic magmatism in south Korea and its tectonic implication. Tectonics 24, TC5002
  31. Yun, H.S. and Hong, S.S., 2003, Geochemistry of granites in the Southern Gimcheon area of Korea. Journal of the Geological Society of Korea, 12, 16-31.