암석학회지 (The Journal of the Petrological Society of Korea)

한국암석학회 (The Petrological Society of Korea)
권호 표지
DOI QR코드

DOI QR Code

지리산 : 지각 깊은 곳을 들여다보는 창문

Jiri Mountain, Korea : A Window into the Deep Crust

  • 송용선 (부경대학교 지구환경과학과) ;
  • 박계헌 (부경대학교 지구환경과학과)
  • Song, Yong-Sun (Department of Earth Environmental Sciences, Pukyong National University) ;
  • Park, Kye-Hun (Department of Earth Environmental Sciences, Pukyong National University)
  • 투고 : 2017.12.13
  • 심사 : 2017.12.28
  • 발행 : 2017.12.31
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

지리산은 한반도 선캠브리아 기반 육괴 중의 하나인 영남육괴의 남서부에 위치하며, 주로 고도변성의 변성암류로 구성되어 있다. 이 지역 지질은 산상과 암석기재적 특성에 의해 구분된 퇴적기원 미그마타이트질 편마암류, 화강암질 편마암, 반상변정질 편마암, 규장질 편마암으로 구분되는 화강암질 편마암류, 차노카이트 및 회장암 등의 고원생대 암석들로 주로 구성되어 있다. 이들 암석들에서 얻어진 연대는, 저어콘의 상속핵들은 조금 더 오래된 연대(>2,020 Ma)를 보이지만, 대체로 약 1,876에서 1,856 Ma 사이이다. 주 변성작용의 시기도 약 1850-1840 Ma이며 광물군과 지질온도압력계로부터 얻어진 변성조건은 4-6 kb, $700-750^{\circ}C$에 이른다. 이러한 결과는 이 지역이 고원생대의 조산운동기에 지각 깊은 곳에서 일어난 강렬한 화강암질 마그마작용과 변성작용을 받았음을 지시한다. 연대가 약간 젊은 차노카이트(1,856-1,865 Ma)와 회장암(ca. 1,861-1,862 Ma)의 연대는 아마도 조산운동기 직후에 판내부에서 시작된 열개로 규장질 및 고철질 마그마작용이 일어났음을 지시하는 것으로 보인다. 결론적으로, 지리산의 암석들은 중 내지 하부지각에서 생성된 것들로 우리가 지각의 내부를 들여다 볼 수 있게 해주는 창문이다.

Jiri Mountain lies in the southwestern portion of the Yeongnam massif, which is one of the Precambrian basement massifs of the Korean Peninsular, consisting essentially of high-grade metamorphic rocks. The geology of the area mainly consists of Paleoproterozoic metasedimentary migmatitic gneisses, granitic gneisses which are classified into granitic gneiss, (K-feldspar porphyroblastic) granitic gneiss and quartzo-feldspathic gneiss, charnockite and anorthosite based on their occurrence and petrographic characteristics. The ages obtained from these rocks mainly span a narrow range between ca. 1,876 and 1,856 Ma although inherited cores of zircons from massive granite gneiss yielded much older age spectrum (>2,029 Ma). The age of major metamorphism is ca. 1850-1840 Ma and the metamorphic condition obtained from mineral assemblages and geothermobarometers is about 4-6 kb and up to $700-750^{\circ}C$. These results indicate that in the area intense granitic magmatism and metamorphism occurred in the deep crust during Paleoproterozoic orogeny. Some younger age of charnockite (1,856-1,865 Ma) and anorthosite (1,861-1,862 Ma) might indicate the beginning of intraplate rifting leading to felsic and mafic magmatism just after the orogeny. In conclusion, the rocks in the Jiri Mountain area which formed at a mid to deep crustal zone provide us windows into the deep crust.

키워드

참고문헌

  1. Chang, H., 1983, Priglacial Landforms in the Eastern Part of the Main Ridge of Mt. Jiri, South Korea. Geography, Korean Geographical Society, 27, 31-50.
  2. Choi, Y.G., Cheong, C.H., Lee, D.S., Kim, S.U., and Kim, S.J., 1964, Explanatory Text of the Geological Map of Dan Sung Sheet (1:50,000), Kyeong Sang Nam Do Korea, 28p.
  3. Choo, S.-H. and Kim, S.-J., 1989, Rb-Sr Age Determinations on the Ryeongnam Massf (II): Granitic Gneisses and Gneissose Granites in the South-Western Jirisan Region. Korean Inst. Energy Res. Research paper KR-86-7, 7-33.
  4. Hwang, I.J. and Jeong, C.S., 1968, Explanatory Text of the Geological Map of Boseong Sheet (1:50,000), Geological Survey of Korea, 29p.
  5. Jeon, J.-Y., 2014, Study on the Intrusive ages and Magma differentiation process in Hadong-Sancheong anorthosite complex. MSc. dissertation, Pukyong National University, 117p.
  6. Jeong, J-G., Kim, W-S., and Watkinson, D.H. 1989, Geologic Structure of Hadong Anorthositic Rocks and Associated titanium Orebody. Journal of Geological Society of Korea, 25, 98-111. (in Korean with English abstract)
  7. Kim, B.K. and Park, B.K., 1966, Explanatory Text of the Geological Map of Dongbok Sheet (1:50,000). Geological Survey of Korea, 33p.
  8. Kim, C.-B. and Turek, A., 1996, Advances in U-Pb zircon geochronology of Mesozoic plutonism in the southwestern part of Ryeongnam massif, Korea, Geochemical Journal, 30, 323-338. https://doi.org/10.2343/geochemj.30.323
  9. Kim, D-Y., Song, Y-S., and Park, K-H., 2001, Sm-Nd mineral ages of charnockites and ilmenite-bearing anorthositic rocks of Jirisan area and their genetic relationship. Journal of Petrological Society of Korea, 10, 27-35. (in Korean with English abstract)
  10. Kim, D-Y., Song, Y-S., and Park, K-H., 2002, Petrogenesis and Metamorphism of Charnockite of Eastern Jirisan Area. Journal of Petrological Society of Korea, 11, 138-156. (in Korean with English abstract)
  11. Kim, N.J. and Kang, P.C., 1965, Explanatory Text of the Chingyo Sheet (1:50,000). Geological Survey of Korea, 34p.
  12. Kim, O.J., Hong, M.S., Park, H.I., Park, Y.D., Kim, K.T. and Yoon S., 1964a, Explanatory Text of the Geological Map of San Cheong Sheet (1:50,000), Geological Survey of Korea, 26p.
  13. Kim, O.J., Hong, M.S., Yun, S.K., Park, H.I., Park, Y.D., Kim, K.T., Lee, H.Y., and Yoon, S., 1964b, Explanatory Text of the Geological Map of Un Bong Sheet (1:50,000), Kyeong Sang Nam Do Korea, 18p.
  14. Kim, S.-W., Kwon, S., Yi, K., and Santosh, M., 2014, Arc magmatism in the Yeongnam massif, Korean Peninsula: imprints of Columbia and Rodinia supercontinents. Gondwana Res. 26, 1009-1027. https://doi.org/10.1016/j.gr.2013.08.020
  15. Kim, Y.-J., 1986, Geochronology and Petrogenesis on the Older Granitic Rocks collected across the Ryeongsam Massif, Korea. Journal of Korean Institute of Mining Geology, 19, Special Issue, 151-162. (in Korean with English abstract)
  16. Kwon, S.-T. and Jeong, J.G., 1990, Preliminary Sr-Nd isotope study of the Hadong-Sanchung anorthositic rocks in Korea: Implication for their origin and for the Precambrian tectonics, Journal of Geological Society of Korea, 26, 341-349.
  17. Lee, J.-M, Jeong, J.-G., and Kim, W.-S., 1999, The Preliminary Study on the Evolution of Hadong Anorthositic Rocks and Their Genetic Relations with Ilmenite-Bearing Ore Bodies, Korea. Journal of Geological Society of Korea, 35, 321-336. (in Korean with English abstract)
  18. Lee, S.-M. 1980, Some Metamorphic Aspects of the Metapelites in Jirisan (Hadong-Sancheong) Region. Journal of Geological Society of Korea, 16, 1-15. (in Korean with English abstract)
  19. Lee, S.M. and Kim, H.S., 1966, Explanatory Text of the Geological Map of Bongnae Sheet (1:50,000), Geological Survey of Korea, 44p.
  20. Lee, S.-M., Na, K.-C., Lee, S.-H. Park, B.-Y., and Lee, S.-W., 1981, Regional Metamorphism of the Metamorphic Rock Complex in the Southeastern Region of the Sobaegsan Massif. Journal of Geological Society of Korea, 17, 169-188. (in Korean with English abstract)
  21. Lee, Y., Cho, M., Cheong, W., and Yi, K., 2014. A massiftype (1.86 Ga) anorthosite complex in the Yeongnam Massif, Korea: late-orogenic emplacement associated with the mantle delamination in the North China Craton. Terra Nova 26, 408-416. https://doi.org/10.1111/ter.12115
  22. Lee, Y., Cho, M., and Yi, K., 2017, In situ U-Pb and Lu-Hf isotopic studies of zircons from the Sancheong-Hadong AMCG suite, Yeongnam Massif, Korea: Implications for the petrogenesis of 1.86 Ga massif-type anorthosite. Journal of Asian Earth Sciences, 138, 629-646. https://doi.org/10.1016/j.jseaes.2017.02.038
  23. Oh, C-W., Jeon, E-Y., Park, B.-Y., Ahn, K.-S., and Lee, J.-H., 2000, Metamorphic evolution of granitic and porphyroblastic gneisses in the Seungju-Suncheon area, the southwestern part of the Sobacksan Massif. Journal of Petrological Society of Korea, 9, 121-141. (in Korean with English abstract)
  24. Park, K.-H., Song, Y.-S., Park, M.-E., Lee, S-G., and Ryu, H.-J., 2000, Petrological, Geochemical and Geochronological Studies of Precambrian Basement in Northeast Asia Region: 1. Age of the Metamorphism of Jirisan Area, Journal of Petrological Society of Korea, 9, 29-39. (in Korean with English abstract)
  25. Son, C.M. and Kim S.J., 1966, Explanatory Text of the Changpyong Sheet (1:50,000). Geological Survey of Korea, 30p.
  26. Son, C.M., Lee, S.M., Won, C.G., Chang, K.H., and Kim, Y.C., 1965, Explanatory Text of the Geological Map of Hwa Gae Sheet (1:50,000), Geological Survey of Korea, 22p.
  27. Song, Y-S., 1999, Granulite xenoliths in porphyroblastic gneiss from Mt. Jiri Area, Sw sobaegsan massif, Korea. Journal of Petrological Society of Korea, 8, 34-45. (in Korean with English abstract)
  28. Song, Y.-S., Kim, D.-Y., and Park, K.-H., 2007, The Overview of Layered structures in Mafic-Ultramafic Macheon Intrusion. Journal of Petrological Society of Korea, 16, 162-179. (in Korean with English abstract)
  29. Turek, A. and Kim, C.-B., 1996, U-Pb zircon ages for Precambrian rocks in southwestern Ryeongnam and southwestern Gyeonggi massifs, Korea, Geochemical Journal, 30, 231-249. https://doi.org/10.2343/geochemj.30.231