영남육괴 남서부 구례군 둥주리봉 화산암복합체에 대한 암석학적 연구

Petrology of the Mt. Dungjuribong Volcanic Complex, Gurye-gun, Southwest of Ryeongnam Massif

  • 고정선 (부산대학교 과학교육연구소) ;
  • 윤성효 (부산대학교 지구과학교육과) ;
  • 김영라 (장영실과학고등학교)
  • Koh, Jeong-Seon (Research Institute of Science Education, Pusan National University) ;
  • Yun, Sung-Hyo (Department of Earth Science, Pusan National University) ;
  • Kim, Young-La (Jangyoungsil Science High School)
  • 발행 : 2009.12.31

초록

영남육괴의 남서부에 위치한 구례군 둥주리봉 화산암복합체는 백악기의 안산암과 유문암으로 구성된다. 화산암류의 $SiO_2$ 함량은, 52.0~78.5 wt.%의 넓은 조성범위를 나타내며, 칼크-알칼리 계열의 분화경향을 나타낸다. 주원소, 미량원소와 희토류원소의 패턴 및 조구조 판별도에 의하면, 연구지역의 화산암류가 지판이 침강 섭입하는 지판경계부에서 생성된 마그마로부터 유래된 대륙연변호 칼크-알칼리암 계열 화산암임을 지시한다. 화산암내 반정광물의 비평형 특징 즉, 휘석 결정 주변의 반응연의 존재, 사장석 결정의 역누대구조와 중심부의 융식구조, 석영 반정의 가장자리의 융식된 구조 등 마그마가 진화하는 동안 경험한 마그마혼합에서 나타나는 증거들이 비교적 잘 관찰된다.

The Mt. Dungjuribong Volcanic Complex located in Gurye-gun, southwest of Ryeongnam massif, composed of Cretaceous andesitic rocks and rhyolite. $SiO_2$ contents of the volcanic rocks range from 52.0 to 78.5 wt.%. The major and trace elements composition, REE patterns and tectonomagmatic discrimination diagrams of volcanic rocks suggest that they are typical of continental margin arc calc-alkaline rocks produced in the subduction environment. The phenocrysts of the volcanic rocks show that they had gone in disequilibrium state, such as reversal zoning and resorbed core of plagioclase, reaction rim around pyroxene and resorbed margins of quartz, which showing the evidence of magma mixing during the evolution of magma.

키워드

참고문헌

  1. 김민석, 윤성효, 고정선, 2008, 영남육괴내 무주 설천응회암의 암석학적 연구. 지질학회지, 4492, 199-217
  2. 김영라, 고정선, 이정현, 윤성효, 2008, 영남육괴 남서부에 분포하는 백악기 화산암류에 대한 암석학적 연구: (1) 승주군 문유산 화산암복합체. 암석학회지, 17(2), 57-82
  3. 남기상, 유환수, 이종덕, 1989, 하동지질도폭(1:50,000). 한국동력자원연구소, 16p
  4. 손치무, 이상만, 원종관, 장기홍, 김영주, 1964, 화개지질도폭(1:50,000). 경상남도, 22p
  5. 유환수, 김용준, 박배영, 1993, 괴목지질도폭(1:50,000). 한국자원연구소, 19p
  6. 이병주, 김정찬, 김유봉, 조등룡, 최현일, 전희영, 김복칠, 1997, 광주지질도폭 (1:25만). 한국자원연구소, 82
  7. 이영엽, 송준호, 2007, 전남 구례군 백악기 구례분지의 층서 및 퇴적환경. 지질학회지, 43, 265-297
  8. 이영엽, 2008, 전남 구례군 백악기 구례분지에서 발견된 공룡뼈 화석. 지질학회지, 44(3), 353-357
  9. 홍승호, 황상구, 1984, 구례지질도폭(1:50,000). 한국동력자원연구소, 22p
  10. Brown, G.M., Thorpe, R.S. and Webb, P.C., 1984, The geochemical characteristic of granitoids in contrasting arc and comments on magma sources. J. Geol. Soc. London, 141, 413-426 https://doi.org/10.1144/gsjgs.141.3.0413
  11. Deer, W.A., Howie, R.A. and Zussman, J., 1972, Rock forming minerals, Vol. 1, orth- and ring silicates. Longmans, Group Ltd, London, England, 77-112
  12. Gill, J,B., 1981, Orogenic andesites and plate tectonics. Springer, Berlin, 390p
  13. Green, T.H., 1980, Island arc and continent-building magmatism;A review of petrogenic models on experimental petrology and geochemistry. Tectonophysics, 63, 367-385 https://doi.org/10.1016/0040-1951(80)90121-3
  14. Irvine, T.N. and Barargar, W.R.A., 1971, A gude to the chemical classification of the common volcanic rocks. Can. J. Earth Sci., 8, 523-548 https://doi.org/10.1139/e71-055
  15. Jakes, P. and White, A.J.R., 1972, Major and trace element abundances in volcanic rocks of orogenic areas. Geol. Soc. Am, Bull., 83, 29-40 https://doi.org/10.1130/0016-7606(1972)83[29:MATEAI]2.0.CO;2
  16. Kuno, H., 1968, Differentiation of basalt magmas. In; Hess H.H. and Poldervaart A. (eds.), Basalts; The Poldervaart treatise on rocks of basaltic composition. Vol. 2, Interscience, New York, 623-688
  17. Le Maitre, R.W., Bateman, P., Dudek, A., Keller, J., Lameyre Le Bas, M.J., Sabine, P.A., Schmid, R., Sorensen, H., Streckeisen, A., Wooldey, A.R. and Zanettin, B., 1989, A classification of igneous rocks and glossary of terms. Blackwell, Oxford, 193p
  18. Lofgren, G., 1970, Experimental devitrification rates of rhyolitic glass. Geol. Soc. Am. Bull., 81, 553-560 https://doi.org/10.1130/0016-7606(1970)81[553:EDRORG]2.0.CO;2
  19. Lofgren, G., 1971a, Spherulitic textures in glassy and crystalline rocks. J. Geophys. Res., 76, 5635-5648 https://doi.org/10.1029/JB076i023p05635
  20. Lofgren, G., 1971b, Experimentally produced devitrification textures in natural rhyolitic glass. Geol. Soc. Am. Bull., 82, 111-124 https://doi.org/10.1130/0016-7606(1971)82[111:EPDTIN]2.0.CO;2
  21. Miyamoto, T., Yanagi, T. and Yun, S.-H., 2003, U-Pb age of clastic zircon in the porphyroblastic gneiss, Gurye area, southwest of Sobaegsan massif., Abstract of Annual meeting of Geological Society of Korea, 29
  22. Morimoto, N., 1988, Nomenclature of pyroxenes. Amer., Min., 73, 1123-1133
  23. Pearce, J.A., 1983, The role of sub-continental lithosphere in magma genesis at destructive plate margins. In continental basalts and mantle xenoliths. Hawkesworth, C. J. and Norry, M. J. (eds.), Nantwich, Shiva. 230-249
  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 Basins (Saunders, A. D. and Norry, M. J. eds.), Geol. Soc. Spic. Publ., 42, 313-345 https://doi.org/10.1144/GSL.SP.1989.042.01.19
  25. Wilson, M., 1989, Igneous petrogenesis. Unwin Hyman, London, 466p
  26. Winchester, J.A. and Floyd, P.A., 1977, Geochemical discrimination of different magma series and their differentiation products using immobile element. Chem. Geol., 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 Planet. Sci. Lett., 50, 11-30 https://doi.org/10.1016/0012-821X(80)90116-8
  28. Yun, S.H., 2002, Cretaceous volcanic activity in the Korean Peninsula. The 1st and 2nd Symposium on the Geology of Korea Special Publication, Korea Institute of Geoscience and Mineral Resources, 157-180