홍성지역 월현리 복합체 내에 분포하는 트라이아스기 심성암류의 지질연대학 및 지구화학적 연구 = Geochronological and Geochemical Studies for Triassic Plutons from the Wolhyeonri Complex in the Hongseong Area, Korea

국문 초록 (Abstract)

한국 경기육괴의 서남부 홍성지역은 지구조적으로 중국의 친링-다비에-수루대와 비교 연장되는 봉합대의 하나로 고려된다. 홍성지역의 중앙부에 위치하는 월현리복합체는 주로 신원생대의 편마암과 고생대 중기의 중-고변성의 편암, 정편마암과 변성염기성화산암으로 주로 구성된다. 이 지역은 트라이아스기 중기에서 말기까지의 암맥상 혹은 암주상의 다양한 관입암이 분포한다. 주 암상은 몬조니암과 반화강암으로 구성되며 부수적으로 소규모 암주상의 몬조섬록암, 섬장암과 섬록암 등이 산출된다. 연구지역 심성암에 대한 SHRIMP U-Pb 저어콘 연대결과는 237 Ma부터 222 Ma의 범위를 보여준다. 연구대상 트라이아스기 심성암은 TaNb의 골, P와 Ti의 결핍과 저장력 원소들이 부화된 경향을 가지는 섭입형 혹은 호상형과 유사한 지화학적 특징을 보여준다. 연구지역 트라이아스기 심성암과 홍성지역의 주 트라이아스기 심성암인 화강암-섬장암은 대부분 칼륨 함량이 높은 고칼륨 캘크-알칼라인에서 쇼쇼나이트까지의 지구조 특징을 가진다. 이들 결과들은 중국의 북중국판과 남중국판의 트라이아스기 충돌이후 생성된 후충돌형 마그마 사건의 지구조적 연결을 가능하게 한다. 결과적으로 홍성지역의 트라이아스기 심성암은 동북아시아의 지구조동력 역사 내 트라이아스기 봉합의 중요한 이해를 제공하여준다.

다국어 초록 (Multilingual Abstract)

The Hongseong area of the southwestern Gyeonggi massif is considered to be part of suture zone that is tectonically correlated with the Qinling-Dabie-Sulu belt of China in terms of the preservation of collisional evidences during Triassic in age. The Wolhyeonri complex, preserved at the center of the Hongseong area, consists mainly of Neoproterozoic orthogneisses and Middle Paleozoic intermediate- to high-grade metamorphic schists, orthogneisses and mafic metavolcanics. The area includes various Middle to Late Triassic intrusives (e.g. dyke or stock). They are mainly monzonite and aplite with small intrusions of monzodiorit, syenite and diorite in composition. The SHRIMP U-Pb zircon ages yield 237 Ma to 222 Ma. The geochemistry of the studied Triassic intrusives show similar subuction- or arc-type signatures having Ta-Nb troughs, depletion of P and Ti, and enrichment of LILEs (large ion lithophile elements). In addition, the Triassic plutons in the Hongseong area, including those from this study, mostly possess high-K calc-alkaline to shoshonitic tectonic affinity. These results could be tectonically correlated to the post-collisional magmatic event following the Triassic collision between the North and South China blocks in China. Therefore, the Triassic plutons in the Hongseong area offer an important insight into the Triassic geodynamic history of the NE Asian region.

참고문헌 (Reference)

1 김성원, "홍성 신리 지역 대리암 내 함석류석 변성염기성암의 암석지화학 연구 및 그 지구조적 의미" 한국암석학회 19 (19): 209-225, 2010

2 김형수, "태백산분지에 분포하는 후기 고생대 평안누층군의 변성-변형작용: 페름-삼첩기 송림 조산운동의 고찰" 한국암석학회 21 (21): 151-171, 2012

3 오창환, "원생대 이후 트라이아스기까지의 남한과 동북아시아의 지구조 진화" 한국암석학회 21 (21): 59-87, 2012

4 정창식, "남한 지역 현생 화강암류의 연대측정 결과 정리" 한국암석학회 21 (21): 173-192, 2012

5 김성원, "경기육괴 남서부 홍성지역 월현리 지구조 복합체의 변성화산암류에 대한 지질연대 및 지구화학 특징" 대한지질학회 46 (46): 453-471, 2010

6 Ludwig, K. R., "User’s manual for Isoplot 3.6: a geochronological toolkit for Microsoft Excel" Berkeley Geochronology Center Special Publication 77-, 2008

7 Williams, I. S., "U-Th-Pb geochronology by ion microprobe, In Applications of Microanalytical Techniques to Understanding Mineralizing Processes" 7 : 1-35, 1998

8 Pearce, J. A., "Trace element discrimination diagrams for the tectonic interpretation of granitic rocks" 25 : 956-983, 1984

9 Streckeisen, A. L., "To each plutonic rock its proper name" 12 : 1-33, 1976

10 Oh, C.W., "The late Permian to Triassic Hongseong-Odesan collision belt in South Korea, and its tectonic correlation with China and Japan" 49 : 636-657, 2007

11 Cho, D. -L., "Termination of the Permo-Triassic Songrim (Indosinian) orogeny in the Ogcheon belt, South Korea: Occurrence of ca. 220 Ma post-orogenic alkali granites and their tectonic implications" 105 : 191-200, 2008

12 Choi, S. J., "Tectonic evolution of the western Gyeonggi Block and construction of geologic DB system" Basic Research Report of the Korea Inst. Geosci. Mineral Res. 420-, 2012

13 Kee, W. S., "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. 242-, 2011

14 Chough, S. K., "Tectonic and sedimentary evolution of the Korean Peninsula: a review and new view" 52 : 175-235, 2000

15 Zhao, Z. -F., "Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen" 328 : 70-88, 2012

16 Steiger, R., "Subcommission of geochronology: convention on the use of decay constants in geo- and cosmo-chronology" 36 : 359-362, 1977

17 Pearce, J. A., "Sources and settings of granitic rocks" 19 : 120-125, 1996

18 Ludwig, K. R., "SQUID 2: a user’s manual" Berkeley Geochronology Center Special Publication 100-, 2009

19 Kim, S. W., "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" 92 : 357-377, 2006

20 Choi, S. G., "Petrology, geochronology and tectonic implications of Mesozoic high Ba°©Sr granites in the Haemi area, Hongseong Belt, South Korea" 18 : 266-281, 2009

21 Seo, J., "Petrology, geochemistry, and geochronology of the post-collisional Triassic mangerite and syenite in the Gwangcheon area, Hongseong Belt, South Korea" 18 : 479-496, 2010

22 Yang, J. -H., "Petrogenesisof post-orogenic syenites in the Sulu Orogenic Belt, East China: geochronological, geochemical and Nd-Sr isotopic evidence" 214 : 99-125, 2005

23 Peng, P., "Petrogenesis of Triassic postcollisional syenite plutons in the Sino-Korean craton: an example from North Korea" 145 : 637-647, 2008

24 Kwon, S., "Multiple generations of mafic-ultramafic rocks from the Hongseong suture zone, western South Korea: Implications for the geodynamic evolution of NE Asia" 160 : 68-83, 2013

25 Cho, M., "Metamorphic evolution of the Imjingang Belt, Korea: Implications for Permo-Triassic collisional orogeny" 49 : 30-51, 2007

26 Kim, J. H., "Mesozoic tectonics in Korea" 13 : 251-265, 1996

27 Sagong, H., "Mesozoic episodic magmatism in South Korea and its tectonic implication" 24 : 2005

28 Zhai, M., "Linking the Sulu UHP belt to the Korean Peninsula: evidence from eclogite, Precambrian basement, and Paleozoic sedimentary basins" 12 : 388-403, 2007

29 Cohen, K.M., "Interaltional Chronostratigraphic Chart" International Commission on Stratigraphy of the International Union of Geological Sciences 2013

30 Kim, S. W., "Geotectonic framework of Permo-Triassic magmatism within the Korean Peninsula" 20 : 865-889, 2011

31 Song, K. Y., "Geological report of the Sokcho-Yangyang sheet (1:50,000)" Daejon, Korea Inst. Geosci. Mineral Res. 68-, 2011

32 Lee, B. J., "Geological report of the Gisan sheet (1:50,000)" Daejon, Korea Inst. Geosci. Mineral Res. 39-, 2006

33 Kim, Y. B., "Geological report of the Gimje sheet (1:50,000)" Daejon, Korea Inst. Geosci. Mineral Res. 32-, 2012

34 Kihm, Y.H., "Geological report of the Gangneung-Jumunjin sheets (1:50,000)" Korea Inst. Geosci. Mineral Res. 62-, 2011

35 Williams, I. S., "Geochronology, and geochemical and Nd-Sr isotopic characteristics, of Triassic plutonic rocks in the Gyeonggi Massif, South Korea: Constraints on Triassic post-collisional magmatism" 107 : 239-256, 2009

36 Kim, J., "Geochronological and geochemical constraints on the petrogenesis of Mesozoic high-K granitoids in the central Korean peninsula" 20 : 608-620, 2011

37 Harris, N. B. W., "Geochemical characteristics of collision-zone magmatism, In Collision Tectonics" Blackwell 1986

38 Seo, J., "Genetic implications of two different ultramafic rocks from Hongseong area in the southwestern Gyeonggi Massif, South Korea" 8 : 539-552, 2005

39 Oh, C. W., "First finding of eclogite facies metamorphic event in South Korea and its correlation with the Dabie-Sulu collision belt in China" 113 : 226-232, 2005

40 Lee, S.H., "Explanatory text of the Geological map of Hong Song Sheet" Geol. Sur. Korea 33-, 1963

41 Kwon, S., "Evidence for Permo-Triassic collision in Far East Asia: The Korean collisional orogen" 279 : 340-349, 2009

42 Sun, S.S., "Chemical and isotopic systematics of oceanic basalt: implications for mantle composition and process, In Magmatism in the Ocean Basins. Geol. Soc. London. Special Publ., v.42" 313-345, 1989