Korean Journal of Mineralogy and Petrology (광물과 암석)

The Petrological Society of Korea & The Mineralogical Society of Korea (한국암석학회 & 한국광물학회)
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Petrology of the Cretaceous Volcanic Rocks in Yeongdo island, Busan

부산 영도 일대의 백악기 화산암류에 대한 암석학적 연구

  • Kim, Dohyoung (Department of Earth Science, Pusan National University) ;
  • Yun, Sung-Hyo (Department of Earth Science, Pusan National University)
  • 김도형 (부산대학교 지구과학과) ;
  • 윤성효 (부산대학교 지구과학과)
  • Received : 2021.11.17
  • Accepted : 2021.12.24
  • Published : 2021.12.31
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Abstract

The volcanic rocks that make up Yeongdo island, an administrative district located on the southern coast of Busan, are composed of andesitic and rhyolitic rocks. Andesitic rock is mainly composed of volcanic breccia has a phenorysts of plagioclase and contains rock fragments. The rhyolitic rock is composed of volcanic angular rock at the base of Mt. Bongnae, and welded tuff forms the main mass of Mt. Bongnae. The fiamme structure can be easily observed with the naked eye, and the higher the altitude, the weaker the welded structure develops and the less the amount of rock fragments and crystals constituting the welded tuff. It is indicated that the magma that formed this study area is related to the tectonic environment of the continental margin related to subduction, and that it erupted after undergoing fractional cystallization at the same time with some contaminant in the continental crust. As a result of analyzing the main elements by altitude, it is believed to be the result of mixing at least 4 times or more of magma batches.

부산광역시 남해안에 위치한 행정자치구 영도(Yeongdo island) 봉래산 일원을 구성하는 화산암류는 안산암질~유문암질암으로 구성된다. 안산암질암은 주로 화산각력암으로 구성되며, 반정으로 사장석을 가지며 다량의 암편(岩片)을 함유하고 있다. 유문암질암은 산출형태에 따라 봉래산 기저부는 화산각력암으로 구성되며, 용결응회암이 봉래산 주산체를 이룬다. 육안으로 피아메 구조를 관찰할 수 있고, 고도가 높아질수록 용결구조는 약하게 발달하고 응회암을 구성하는 암편 및 결정 함량은 적어진다. 본 연구지역을 형성한 마그마는 섭입작용과 관련된 대륙연변부의 조구조 환경과 관련 있으며, 약간의 대륙지각의 혼염과 동시에 분별결정작용을 겪은 뒤 분출하였음을 지시한다. 고도별 주원소를 분석한 결과, 최소 4회 이상의 마그마 배취(magma batches)가 주입되어 혼합이 일어난 결과로 생각된다.

Keywords

Acknowledgement

이 연구는 기상청 기상·지진 See-At 기술개발연구사업(KMI2018-02710)의 지원으로 수행되었습니다.

References

  1. Baier, J., Audetat, A. and Keppler, H., 2008, The origin of the negative niobium tantalum anomaly in subduction zone magmas. Earth and Planetary Science Letter, 267, 290-300. https://doi.org/10.1016/j.epsl.2007.11.032
  2. Cha, M.S., 1976, Petrological study on the Bulgugsa acidic igneous rocks in Busan area. Journal of Korea Institute of Mining Geology, 9, 85-106.
  3. Cha, M.S., 1985, Ring structure in the southeastern Kyeongsang basin(1), Journal of College of Education, Pusan National University, 11, 369-386.
  4. Cha, M.S. and Yun, S.H., 1982, Cretaceous volcanic activity in the vicinity of Busan: Jangsan caldera remnant structure, Journal of Natural Science, Pusan National University, 34, 377-388.
  5. Chang, T.W., Kang, P.J., Park, B.H., Hwang, S.K., and Lee, D.W., 1983, Explanation text and geologic map(1:50,000) of Pusan and Gadeok sheet. KIGAM, 53p.
  6. Gill J., 1981. Orogenic andesites and plate tectonics. Springer Verlag, Berlin, 392p.
  7. Hwang, S.K. and Kim, S.W., 1994a, Petrology of Cretaceous volcanic rocks in the Milyang-Yangsan area, Korea: Petrotectonic setting. Journal of the Geological Society of Korea, 30, 229-241.
  8. Hwang, S.K. and Kim, S.W., 1994b, Petrology of Cretaceous volcanic rocks in the Miryang-Yangsan area, Korea (II): Petrogenesis. Journal of the Geological Society of Korea, 30, 563-577.
  9. Hwang, S.K., 2012, Tectonic setting and arc volcanisms of the Gyeongsang Arc in the southeastern Korean Peninsula. Journal of the Petrological Society of Korea, 21, 367-383. https://doi.org/10.7854/JPSK.2012.21.3.367
  10. Irvine, T.N. and Baragar, W.R.A., 1971, A guide to the chemical classification of the common volcanic corks. Canadian Journal of Earth Science, 8, 523-548. https://doi.org/10.1139/e71-055
  11. Jwa, Y.J., 1998, Petrology of the igneous rocks in the Goseong area, Gyeongsang Basin II. Trace element geochemistry and Rb-Sr radiometric age. Economic and Environmental Geology, 31, 473-483.
  12. Kim, H.J., 2009, Petrological study on the felsic volcanic rocks in the Jangsan, Pusan. Pusan National University, Master thesis, 82p.
  13. Kim, J.S. and Yun, S.H., 1993, Petrology of the Cretaceous volcanic rocks in Pusan area, Korea. The Journal of the Petrological Society of Korea, 2, 156-166
  14. Kim, J.S., Lee, J.D. and Jeong, N.I., 1999, Petrochemical study on the Cretaceous volcanic rocks in the Namhae island, Korea. The Korean Earth Science Society, 20, 640-651.
  15. Kim, N.-H., Song, Y.-S., Park, K.-H. and Lee, H-S., 2009, Shrimp U-Pb zircon ages of the granite gneisses from the Pyeonghae area of the northeastern Yeongnam Massif (Sobaeksan Massif). Journal of Petrological Society of Korea, 18, 31-47.
  16. Kim, S.W. and Lee, Y.G., 1981, Petrology and Structural Geology of the Late Cretaceous Volcanic Rocks in the Northeastern Part of Yucheon Basin. Journal of the Korean Institute of Mining Geology, 14, 35-49.
  17. Koh, J.S., Kim, E.H., and Yun, S.H., 2004, Petrology of the Cretaceous igneous rocks in Gadeog island, Busan, Korea. Journal of Petrological Society of Korea, 13, 47-63.
  18. Kuno, H., 1968, Differentiation of basalt magmas. In: Hess H.H. and Poldevaart A. (eds.), Basalts: The Poldervarrt treatise on rocks of basaltic composition. 2, Interscience, New York, 623-688.
  19. Le Maitre, R.W., 1989, A propose by the IUGS subcomission on the systematics of igneous rocks for a chemical classification of volcanic rocks based on the total alkali silica (TAS) diagram. Australian Journal of Earth Science, 31, 243-255. https://doi.org/10.1080/08120098408729295
  20. Martin, H., 1987, Petrogenesis of Archaean trondhjemites, tonalites, and granodiorites from eastern Finland: major and trace element geochemistry. Journal of Petrology, 28(5), 921-953. https://doi.org/10.1093/petrology/28.5.921
  21. Park, C.S., Shin, H.S., Oh, H., Moon, J.H., Cho, H. and Cheong, C.S., 2013, Determination of trace elements in geological reference materials G-3, GSP-2 and SGD-1aby low dilution glass bead digestion and ICP-MS, Geo-standards and Geoanalytical Research, 37, 361-368. https://doi.org/10.1111/j.1751-908X.2012.00212.x
  22. Pearce, J.A., Harris, N.B.W. and Tindle, A.G., 1984, Trace element discrimination diagram for the tectonic interpretation of granitic rocks. Journal of Petrology, 25, 956-983. https://doi.org/10.1093/petrology/25.4.956
  23. Son, C.M., Lee, S.M., Kim, Y.G., KIm, S.W., and Kim, H.S., 1978, Explanatory text of the geological map (1:50,000) of Dongrae and Weolnae sheets (Sheet-7019- IV-I). Korea Research Institute of Geological and Mineral Resources, Seoul, Korea, 27p.
  24. Sun, S.S. and McDonough, W.F., 1989, Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In Magmatism in the Ocean Basisn. In: Saunders, A.D. and Norry, M.J. (des.), Geological Society Special Publication, 42, 313-345.
  25. Sung, J.G., Kim, J.S. and Lee, J.D., 1998, Petrochemical Study on the Cretaceous Volcanic Rocks in Kyeongsang Basin, Korea: Possibility of Magma Heterogeneity. Economic and Environmental Geology, 31(3), 249-264.
  26. Winchester, J.A. and Floyd, P.A., 1977, Geochemical discrimination of different magma series and their differentiation products using immobile element. Chemical Geology, 20, 325-343. https://doi.org/10.1016/0009-2541(77)90057-2
  27. Wood, D.A., 1980, The application of a Th-Hf-Ta diagram to problems of tectonomagmatic classification and to establishing the nature of crustal contamination of basaltic lavas of the British Tertiary volcanic province. Earth and Planetary Science Letter, 50, 11-30. https://doi.org/10.1016/0012-821X(80)90116-8
  28. Yun, S.H. and Sang, K.N., 1994, Geochronology and cauldron structure of the Cretaceous volcanic complexes in southern Kyeongsang basin, Korea. Journal of Korean Earth Science Society, 15, 376-391.
  29. Yun, S.H., 1998, Volcanic activiy and petrology of the Cretaceous volcanic complex in Yuchon volcanic field of southeastern Korea. Journal of Korean Earth Science Society, 19, 408-424.
  30. Yun, S.H., Lee J.D., Lee, S.W., Koh, J.S. and Seo, Y.J., 1997, Petrology of the volcanic rocks in Geoje Island, South Korea. Journal of the Petrological Society of Korea, 6, 1-18.