Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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Geochronological and Geotectonic Implications of the Serpentinite Bodies in the Hongseong Area, Central-western Korean Peninsula

한반도 중서부 홍성지역 내에 분포하는 사문암체의 지질연대학 및 지구조적 의미

  • Kim, Sung Won (Geological Research Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Park, Seung-Ik (Geological Research Division, Korea Institute of Geoscience and Mineral Resources)
  • 김성원 (한국 지질자원연구원 국토지질연구본부) ;
  • 박승익 (한국 지질자원연구원 국토지질연구본부)
  • Received : 2016.08.10
  • Accepted : 2016.08.31
  • Published : 2016.08.28
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Abstract

The Hongseong area of the central-western Korean Peninsula is considered to be a part of collision zone that is tectonically correlated to the Qinling-Dabie-Sulu belt of China. The area includes the elliptical-shaped serpentinized ultramafic bodies, together with mafic rocks. The studied bodies are in contact with the surrounded Neoproterozoic alkali granites at the Baekdong and Wonnojeon bodies and the Paleoproterozoic Yugu gneiss at the Bibong body. The Baekdong body contains the blocks of the Neoproterozoic alkali granites and the Late Paleozoic metabasites. The Bibong body also includes the Neoproterozoic alkali granite blocks. The Mesozoic intrusive rocks are also recognized at the Baekdong, Wonnojeon and Bibong bodies. On the other hand, the Early Cretaceous volcanic rocks are occurred at the Bibong body. The detrital zircon SHRIMP U-Pb ages of the serpentinites at three bodies range variously from Neoarchean to Middle Paleozoic at the Baekdong body, and from Neoarchean to Early Cretaceous at the Wonnojeon and Bibong bodies. Although serpentinization does not generally produce minerals suitable for direct isotopic dating, the youngest Middle Paleozoic age at the Baekdong body and the Early Cretaceous age at the Wonnojeon and Bibong bodies indicate the possible upper age limit for the (re)serpentinization. Especially, the Early Cretaceous serpentinization ages may be related to the widespread Early Cretaceous igneous activity in the central-southern Korean Peninsula. Age results for the serpentinite bodies and the included blocks of the studied serpentinized ultramafic bodies in the Hongseong area, therefore, provide several possible interpretations for the serpentinization ages of the ultramafic rocks as well as the geotectonic implications of serpentinization, requiring more detailed study including other serpentinized ultramafic bodies in the Hongseong area.

한반도 중서부 홍성지역은 지구조적으로 중국의 친링-다비에-수루대와 대비되는 충돌대일 가능성이 고려되는 지역이다. 홍성지역은 다수의 다양한 시기의 렌즈상 사문암체가 렌즈상 염기성암체와 함께 분포한다. 주 연구대상 사문암체 중 백동과 원노전 암체는 신원생대 알칼리화강암과 그리고 비봉암체는 고원생대 유구편마암과 접촉한다. 백동암체는 신원생대 알칼리화강암 암괴 및 고생대 후기 변성염기성 암괴를 포함하며, 비봉암체는 신원생대 알칼리화강암의 암괴를 포함한다. 세 암체 모두에서 중생대 관입암체가 인지되며, 비봉암체는 백악기의 화산암을 포함한다. 사문암체의 사문암에 대한 SHRIMP U-Pb 쇄설성 저어콘 연대결과는 백동 암체에서 시생대 후기부터 고생대 중기, 원노전과 비봉 암체에서 시생대 후기부터 백악기 전기까지 연대 범위를 보여준다. 비록 사문암화 과정에서 연대측정을 수행할 광물이 생성되지는 않지만, 가장 젊은 쇄설성 저어콘의 연대인 백동 사문암체의 고생대 중기와 원노전과 비봉 사문암체의 백악기 연대는 지금까지 알려진 사실과 달리 이들 사문암체가 고생대 중기 이후 혹은 백악기 전기 이후 사문암화되었을 가능성 또는 재동되었을 가능성에 대한 새로운 정보를 제공한다. 특히, 사문암체 내에서 나타나는 백악기 초기의 연대들은 사문암화 작용이 한반도 중서부 내에 분포하는 백악기 초기 화성작용과 관련되었을 가능성을 배제할 수 없다. 결과적으로 홍성지역의 연구대상 사문암체의 사문암과 사문암 내의 다양한 시기의 암괴들로부터 측정된 연대 결과들은 사문암화된 초염기성암의 사문암화 시기 및 사문암화 되는 지구조 환경 해석에 여러 가지 가능성을 제공하며, 연구지역의 다른 사문암체들을 포함한 사문암체에 대한 좀 더 자세한 지질연대학적 연구가 필요함을 지시한다.

Keywords

References

  1. Arai, S., Tamura, A., Ishimaru, S., Kadoshima, K. and Lee, Y.I. (2007) Petrology of the Yugu peridotites in the Gyeonggi Massif, South Korea: implications for its origin and hydration process. Island Arc, v.17, p.485-501.
  2. Choi, S.J., Kee, W.S., Koh, H.J., Kwon, C.W., Kim, B.C., Kim, S.W., Kim, Y.B., Khim, Y.H., Kim, H.C., Park, S.-I., Song, K.Y., Yeon, Y.K., Lee, S.S., Lee, S.R., Lee, Y.S., Lee, H.J., Cho, D.R., Choi, B.Y., Hwan, J.K., Hyeon, H.J., Hwang, J.H. and Lee, J.A. (2014) Tectonic evolution of the western Gyeonggi block and construction of geologic DB system. Basic Research Report of the Korea Institute of Geoscience and Mineral Resources, 420p (In Korean with English summary).
  3. Kee, W.S., Koh, H.J., Kim, S.W., Kim, Y.B., Khim, Y.H., Kim, H.C., Park, S.-I., Song, K.Y., Lee, S.R., Lee, Y.S., Lee, H.J., Cho, D.R., Choi, B.Y., Choi, S.J. and Hwang, J.H. (2011) Tectonic evolution of the upper crustal units in the mid-western part of the Korean peninsula. Basic Research Report of the Korea Inst. Geosci. Mineral Res., 242p.
  4. Kim, S.W., Kee,W.-S., Lee, S.R., Santosh, M. and Kwon, S. (2013) Neoproterozoic plutonic rocks from the western Gyeonggi massif, South Korea: implications for the amalgamation and break-up of the Rodinia supercontinent. Precambrian Research v.227, p.349-367. https://doi.org/10.1016/j.precamres.2012.01.014
  5. Kim, S.W., Kwon, S., Park, S.-I., Lee, C., Cho, D.-L., Lee, H.-J., Ko, K. and Kim, S.J. (2016) SHRIMP U-Pb dating and geochemistry of the Cretaceous plutonic rocks in the Korean Peninsula: A new tectonic model of the Cretaceous Korean Peninsula. Lithos, v.262, p.88-106. https://doi.org/10.1016/j.lithos.2016.06.027
  6. Kim, S.W., Kwon, S., Ryu, I.-C., Jeong, Y.-J., Choi, S.J., Kee, W.-S., Yi, K., Lee, Y.S., Kim, B.C. and Park, D.W. (2012) Characteristics of the Early Cretaceous igneous activity in the Korean Peninsula and tectonic implications. Journal of Geology, v.120, p.625-646. https://doi.org/10.1086/667811
  7. Kim, S.W., Kwon, S., Santosh, M., Williams, I.S. and Yi, K. (2011b) A Paleozoic subduction complex in Korea: SHRIMP zircon U-Pb ages and tectonic implications. Gondwana Res., v.20, p.890-903. https://doi.org/10.1016/j.gr.2011.05.004
  8. Kim, S.W., Park, S.-I., Ko, K., Lee, H.-J., Koh, H.J., Kihm, Y.H. and Lee, S.R. (2014c) 1:100,000 Tectonostratigraphic map of the Hongseong area, map 1: Solid Geology Interpretation. Korea Institution of Geoscience and Mineral Resources.
  9. Kim, S.W., Oh, C.W., Williams, I.S., Rubbato, D., Ryu, I.-C., Rajesh, V.J., Kim, C.-B., Guo, J. and Zhai, M. (2006) Phanerozoic high-pressure eclogite and intermediate- pressure granulite facies metamorphism in the Gyeonggi block, South Korea: implications for the eastward extension of the Dabie-Sulu continental collision zone. Lithos, v.92, p.357-377. https://doi.org/10.1016/j.lithos.2006.03.050
  10. Kim, S.W., Santosh, M., Park, N. and Kwon, S. (2011c) Forearc serpentinite mélange from the Hongseong suture, South Korea. Gondwana Research, v.20, p.852-864. https://doi.org/10.1016/j.gr.2011.01.012
  11. Kim, S.W., Williams, I.S., Kwon, S. and Oh, C.W. (2008) SHRIMP zircon geochronology and geochemical characteristics of metaplutonic rocks from the south-western Gyeonggi block, Korea: implications for Paleoproterozoic to Mesozoic tectonic links between the Korean Peninsula and eastern China. Precambrian Research, v.162, p.475-497. https://doi.org/10.1016/j.precamres.2007.10.006
  12. Kwon, S., Kim, S.W. and Santosh, M. (2013) Multiple generations of mafic-ultramafic rocks from the Hongseong suture zone, western South Korea: implications for the geodynamic evolution of NE Asia. Lithos, v.160-161, p.68-83. https://doi.org/10.1016/j.lithos.2012.11.011
  13. Kwon, S., Sajeev, K., Mitra, G., Park, Y., Kim, S.W. and Ryu, I.-C. (2009) Evidence for Permo-Triassic collision in Far East Asia: The Korean collisional orogen. Earth Planet. Sci. Lett., v.279, p.340-349. https://doi.org/10.1016/j.epsl.2009.01.016
  14. Ludwig, K.R, (2008) In: User's Manual for Isoplot 3.6: a Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center Special Publication, Berkeley.
  15. Ludwig, K.R. (2009) User's Manual for SQUID 2. Berkeley Geochronology Center Special Publication, Berkeley.
  16. Oh, C.W., Choi, S.G., Seo, J., Rajesh, V.J., Lee, J.H., Zhai, M. and Peng, P. (2009) Neoproterozoic tectonic evolution of the Hongseong area, the southwestern part of Gyeonggi Massif, South Korea; implication for the tectonic evolution of Northeast Asia. Gondwana Research, v.16, p.272-284. https://doi.org/10.1016/j.gr.2009.04.001
  17. Oh, C.W., Choi, S.G., Song, S.W. and Kim, S.W. (2004) Metamorphic evolution of the Baekdong metabasite in the Hongseong area, South Korea and its relationship with the Sulu collision belt of China. Gondwana Research, v.7, p.809-816. https://doi.org/10.1016/S1342-937X(05)71065-0
  18. Oh, C.W., Kim, S.W., Choi, S.G., Zhai, M., Guo, J. and Sajeev, K. (2005) First finding of eclogite facies metamorphic event in South Korea and its correlation with the Dabie-Sulu collision belt in China. Journal of Geology, v.113, p.226-232. https://doi.org/10.1086/427671
  19. Oh, C.W., Rajesh, V.J., Seo, J., Choi, S.-G. and Lee, J.H. (2010) Spinel compositions and tectonic relevance of the Bibong ultramafic bodies in the Hongseong collision belt, South Korea. Lithos, v.117, p.198-208. https://doi.org/10.1016/j.lithos.2010.02.015
  20. Oh, C.W., Seo, J., Choi, S.G., Rajesh, V.J. and Lee, J.H., 2012. U-Pb SHRIMP zircon geochronology, petrogenesis, and tectonic setting of the Neoproterozoic Baekdong ultramafic rocks in the Hongseong collision belt, South Korea. Lithos, v.128-131, p.100-112. https://doi.org/10.1016/j.lithos.2011.10.008
  21. Park, S.-I., Kim, S.W., Kwon, S., Thanh, N.X., Yi, K. and Santosh, M. (2014a) Paleozoic tectonics of the southwestern Gyeonggi massif, South Korea: insight from geochemistry, chromian-spinel chemistry and SHRIMP U-Pb geochronology. Gondwana Research, v.26, p.684-698. https://doi.org/10.1016/j.gr.2013.07.015
  22. Park, S.-I., Kwon, S., Kim, S.W., Yi, K. and Santosh, M, (2014b) Continental origin of the Bibong eclogite, southwestern Gyeonggi massif, South Korea. Journal of Asian Earth Sciences, v.95, p.192-202. https://doi.org/10.1016/j.jseaes.2014.08.024
  23. Seo, J., Choi, S.-G., Oh, C.W., Kim, S.W. and Song, S.H. (2005) Genetic implications of two different ultramafic rocks from Hongseong area in the southwestern Gyeonggi Massif, South Korea. Gondwana Research, v.8, p.539-552. https://doi.org/10.1016/S1342-937X(05)71154-0
  24. Seo, J., Oh, C.W., Choi, S.G. and Rajesh, V.J. (2013) Two ultramafic rock types in the Hongseong area, South Korea: tectonic significance for northeast Asia. Lithos, v.175-176, p.30-39. https://doi.org/10.1016/j.lithos.2013.04.014
  25. Song, S.H. and Song, Y.S. (2001) Mineralogy and geochemistry of ultramafic rocks from the Singok Area, Western Part of Chungnam. Economic and Environmental Geology, v.34, p.395-415.
  26. Song, S.H., Choi, S.G., Oh, C.H., Seo, J. and Choi, S. (2004) Petrography and geochemistry of the ultramafic rocks from the Hongseong and Kwangcheon areas, Chungcheongnam-Do. Economic and Environmental Geology, v.37, p.477-497.
  27. Song, S.H., Choi, S.G. and Woo, J.G. (1997) Genetic implications of ultramafic rocks from the Bibong area in the Gyeonggi gneiss complex. Economic and Environmental Geology, v.30, p.477-491.
  28. Steiger, R. and Jager, E. (1977) Subcommission of geochronology: convention on the use of decay constants in geo- and cosmo-chronology. Earth and Planetary Science Letters, v.36, p.359-362. https://doi.org/10.1016/0012-821X(77)90060-7
  29. Williams, I.S. (1998) U-Th-Pb geochronology by ion microprobe. In: McKibben, M. A., Shanks, W.C.I.I.I., Ridley, W.L. (Eds.), Applications of Microanalytical Techniques to Understanding Mineralizing Processes, vol. 7. Society of Economic Geologists, Socorro, Reviews in Economic Geology, pp.1-35.
  30. Williams, I.S., Cho, D.-L. and Kim, S.W. (2009) Geochronology, and geochemical and Nd-Sr isotopic characteristics, of Triassic plutonic rocks in the Gyeonggi Massif, South Korea: constraints on Triassic post-collisional magmatism. Lithos, v.107, p.239-256. https://doi.org/10.1016/j.lithos.2008.10.017
  31. Wu, Y.-K. and Suh, M.-C. (2000) Petrological study on the ultramafic rocks in Choongnam area. Journal of the Korean Earth Science Society, v.21, p.323-336.