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http://dx.doi.org/10.9719/EEG.2021.54.2.271

Structural Geometry, Kinematics and Microstructures of the Imjingang Belt in the Munsan Area, Korea  

Lee, Hyunseo (Department of Earth System Sciences, Yonsei University)
Jang, Yirang (Department of Earth and Environmental Sciences, Chonnam National University)
Kwon, Sanghoon (Department of Earth System Sciences, Yonsei University)
Publication Information
Economic and Environmental Geology / v.54, no.2, 2021 , pp. 271-283 More about this Journal
Abstract
The Imjingang Belt in the middle-western Korean Peninsula has tectonically been correlated with the Permo-Triassic Qinling-Dabie-Sulu collisional belt between the North and South China cratons in terms of collisional tectonics. Within the belt, crustal-scale extensional ductile shear zones that were interpreted to be formed during collapsing stage with thrusts and folds were reported as evidence of collisional events by previous studies. In this study, we tried to understand the nature of deformation along the southern boundary of the belt in the Munsan area based on the interpretations of recently conducted structural analyses. To figure out the realistic geometry of the study area, the down-plunge projection was carried out based on the geometric relationships between structural elements from the detailed field investigation. We also conducted kinematic interpretations based on the observed shear sense indicators from the outcrops and the oriented thin-sections made from the mylonite samples. The prominent structures of the Munsan area are the regional-scale ENE-WSW striking thrust and the N-S trending map-scale folds, both in its hanging wall and footwall areas. Shear sense indicators suggest both eastward and westward vergence, showing opposite directions on each limb of the map-scale folds in the Munsan area. In addition, observed deformed microstructures from the biotite gneiss and the metasyenite of the Munsan area suggest that their deformation conditions are corresponding to the typical mid-crustal plastic deformation of the quartzofeldspathic metamorphic rocks. These microstructural results combined with the macro-scale structural interpretations suggest that the shear zones preserved in the Munsan area is mostly related to the development of the N-S trending map-scale folds that might be formed by flexural folding rather than the previously reported E-W trending crustal-scale extensional ductile shear zone by Permo-Triassic collision. These detailed examinations of the structures preserved in the Imjingang Belt can further contribute to solving the tectonic enigma of the Korean collisional orogen.
Keywords
Imjingang Belt; ductile shear zone; collisional orogeny; collapsing stage; deformation condition;
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1 Stallard, A. and Hickey, K. (2001) Fold mechanisms in the Carton Schist: Constraints on the contribution of flexural flow. Journal of Structural Geology, v.23, p.1865-1881. doi: 10.1016/s0191-8141(01)00032-3   DOI
2 Stipp, M., Stunitz, H., Heilbronner, R. and Schmid, S.M. (2002a) The eastern Tonale fault zone: a 'natural laboratory' for crystal plastic deformation of quartz over a temperature range from 250 to 700 ℃. Journal of Structural Geology, v.24, p.1861-1884. doi: 10.1016/s0191-8141(02)00035-4   DOI
3 Stipp, M., Stunitz, H., Heilbronner, R. and Schmid, S.M. (2002b). Dynamic recrystallization of quartz: correlation between natural and experimental conditions. In: De Meer, S., Drury, M.R., De Bresser, J.H.P., Pennock, G.M. (Eds.), Deformation Mechanism, Rheology and Tectonics: Current Status and Future Perspectives vol. 200, Special Publications of the Geological Society of London: London, UK, p.171-190. doi: 10.1144/gsl.sp.2001.200.01.11
4 Tullis, J. and Yund, R.A. (1987) Transition from cataclastic flow to dislocation creep of feldspar: Mechanisms and microstructure, Geology, v.15, p.606-609. doi: 10.1130/0091-7613(1987)15<606:tfcftd>2.0.co;2   DOI
5 Bell, T.H. and Johnson, S.E. (1989) The role of deformation partitioning in the deformation and recrystallization of plagioclase and K-feldspar in the Woodroffe thrust mylonite zone, Central Australia. Journal of Metamorphic Geology, v.7, p.151-168. doi: 10.1111/j.1525-1314.1989.tb00582.x   DOI
6 Chang, K.-H. and Zhao, X. (2012) North and South China suturing in the east end: What happened in Korean Peninsula?. Gondwana Research, v.22, p.493-506. doi: 10.1016/j.gr.2011.12.010   DOI
7 Cho, M., Kwon, S.-T., Ree, J.-H. and Nakamura, E. (1995) High-pressure amphibolite of the Imjingang belt in the Yeoncheon-Cheongok area. The Journal of Petrological Society of Korea, v.4, p.1-19 (in Korean with English abstract).
8 Cho, M., Kim , Y. and Ahn, J. (2007) Metamorphic evolution of the Imjingang Belt, Korea: implications for Permo-Triassic collisional orogeny. International Geology Review, v.49, p.30-51. doi: 10.2747/0020-6814.49.1.30   DOI
9 Zhai, M.G., Guo, J., Li, Z., Chen, D., Peng, P., Li, T., Hou, Q. and Fan, Q. (2007) Linking the Sulu UHP belt to the Korean Peninsula: evidence from eclogite, Precambrian basement, and Paleozoic sedimentary basins. Gondwana Research, v.12, p.388-403. doi: 10.1016/j.gr.2007.02.003   DOI
10 Yin, A. and Nie, S. (1993) An indentation model for the north and south China collision and the development of the Tan-Lu and Honam fault systems, eastern Asia. Tectonics, v.12, p.801-813. doi: 10.1029/93tc00313   DOI
11 Hanmer, S.K. (1982) Microstructure and geochemistry of plagioclase and microcline in naturally deformed granite. Journal of Structural Geology, v.4, p.197-213. doi: 10.1016/0191-8141(82)90027-X   DOI
12 Choi, S.-J., Lee, S.R., Kim, K.B., Kim, J.R. and Kim, B.C. (1998) Explanatory text of the Geological map of Munsan sheet (1:50,000). Korea Institute of Geology, Mining and Materials, 79p. (in Korean with English summary)
13 Chwae, U. and Choi, S.-J. (2009) Stratigraphic and Structural Review of Yeoncheon Group and Imjingang Fold Belt, and Its Edge of Distribution. Economic and Environmental Geology, v.42, p.627-634 (in Korean with English abstract)
14 Chwae, U., Choi, S.-J., Park, K.H. and Kim, K.B. (1996) Explanatory text of the Geological map of Cheolwon-Majwonri sheet (1:50,000). Korea Institute of Geology, Mining and Materials, 31p. (in Korean with English summary)
15 Debat, P., Soula, J.C., Kubin, L. and Vidal, J.L. (1978) Optical studies of natural deformation microstructures in feldspars (gneiss and pegmatites from Occitania, Southern France). Lithosphere, v.11, p.133-145. doi: 10.1016/0024-4937(78)90004-x   DOI
16 Ernst, W.G. and Liou, J.G. (1995) Contrasting plate-tectonic styles of the Qinling-Dabie-Sulu and Franciscan metamorphic belts. Geology, v.23, p.353-356. doi: 10.1130/0091-7613(1995)023<0353:cptsot>2.3.co;2   DOI
17 Hirth, G. and Tullis, J. (1992) Dislocation creep regimes in quartz aggregates. Journal of Structural Geology, v.14, p.145-159. doi: 10.1016/0191-8141(92)90053-Y   DOI
18 Ishiwatari, A. and Tsujimori, T. (2001) Late Paleozoic HighPressure Metamorphic Belts in Japan and Sikhote-Alin. Possible oceanic extension of the Chinese Dabie-Su-Lu Suture detouring Korea. Gondwana Research, v.4, p.636-638. doi: 10.1016/s1342-937x(05)70439-1   DOI
19 Kee, W.-S., Cho, D.-L., Kim, B.C. and Jin, K. (2005) Geological report of the Pocheon Sheet (1:50,000). Korea Institute of Geoscience and Mineral Resources, 69p. (in Korean with English summary)
20 Isozaki, Y., Aoki, K., Nakama, T. and Yanai, S. (2010) New insight into a subduction-related orogen: A reappraisal of the geotectonic framework and evolution of the Japanese Islands. Gondwana Research, v.18, p.82-105. doi: 10.1016/j.gr.2010.02.015   DOI
21 Kee, W.-S., Lim, S.-B., Kim, H., Kim, B.C., Hwang, S.K., Song, K.-Y. and Kihm, Y.,-H. (2008) Geological report of the Yeoncheon Sheet (1:50,000). Korea Institute of Geoscience and Mineral Resources, 83p. (in Korean with English summary)
22 Kim, I., Kim, A.-J., Woo, H. and Park, S.-I. (2019) Geological Structures of the Taean Formation in the Gomseom Area, Southwestern Gyeonggi Massif. Economic and Environmental Geology, v.52, p.159-168 (in Korean with English abstract). doi: 10.9719/EEG.2019.52.2.159   DOI
23 Korea Institute of Geoscience and Mineral Resources (KIGAM) (2001) 1:1,000,000 Tectonic Map of Korea.
24 Kwon, S., Sajeev, K, Mitra, G., Park, Y, Kim, S.W. and Ryu, I.C. (2009) Evidence of Triassic collision in Far East Asia: the Korean collisional orogen. Earth and Planetary Science Letters, v.279, p.340-349. doi: 10.1016/j.epsl.2009.01.016   DOI
25 Kim, H.S., Kwon S., Kim, S.W. and Santosh, M. (2018) Permo-Triassic high-pressure metamorphism in the central western Korean Peninsula, and its link to Paleo-Tethyan Ocean closure: Key issues revisited. Geoscience Frontiers, v.9, p.1325-1335. doi: 10.1016/j.gsf.2018.01.007   DOI
26 Kim, J.-N., Ree, J.-H, Kwon, S.T., Park, Y., Choi, S.-J. and Cheong, C.-S. (2000) The Kyeonggi shear zone of the central Korean peninsula: Late orogenic imprint of the North and South China collision. The Journal of Geology, v.108, p.469-478. doi: 10.1086/314412   DOI
27 Lee, B.Y., Oh, C.W., Cho, D.L., Zhai, M., Lee, B.C., Peng, P. and Yi, K. (2019) The Devonian back-arc basin and Triassic arc-continent collision along the Imjingang belt in the Korean Peninsula and their tectonic meaning. Lithos, v.328-329, p.276-296. doi: 10.1016/j.lithos.2019.01.011   DOI
28 Kim, O.J. (1973) The Stratigraphy and Geologic Structure of the Metamorphic Complex in the Northwestern Area of the Kyonggi Massif. Journal of the Korean Institute of Mining Geology, v.6, p.201-218 (in Korean with English abstract).
29 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. Lithosphere, v.92, p.357-377. doi: 10.1016/j.lithos.2006.03.050   DOI
30 Kim, S.W., Santosh, M., Park, N. and Kwon, S. (2011) Forearc serpentinite melange from the Hongseong suture, South Korea. Gondwana Research, v.20, p.852-864. doi: 10.1016/j.gr.2011.01.012   DOI
31 Marshak, S. and Mitra, G. (1988) Basic Methods of Structural Geology. Prentice Hall, New Jersey, 446p.
32 Metcalfe, I. (2006) Paleozoic and Mesozoic tectonic evolution and paleography of East Asian crustal fragments: The Korean Peninsula in context. Gondwana Research, v.9, p.24-46. doi: 10.1016/j.gr.2005.04.002   DOI
33 Mitra, G. (1978) Ductile deformation zones and mylonites: the mechanical processes involved in the formation of crytstalline basement rocks. American Journal of Science, v.278, p.1057-1084. doi: 10.2475/ajs.278.8.1057   DOI
34 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. doi: 10.1086/427671   DOI
35 Ree, J.-H., Cho, M., Kwon, S.-T. and Nakamura, E. (1996) Possible eastward extension of Chinese collision belt in South-Korea: the Imjingang belt. Geology, v.24, p.1071-1074. doi: 10.1130/0091-7613(1996)024<1071:peeocc>2.3.co;2   DOI
36 Park, S.-I. (2017) A Preliminary Study on the Exhumation Mechanism of the Paleozoic Gwangcheon Gneiss in the Southwestern Margin of the Gyeonggi Massif. Economic and Environmental Geology, v.50, p.525-535 (in Korean with English abstract). doi: 10.9719/EEG.2017.50.6.525   DOI
37 Passchier, C.W. and Trouw, R.A.J. (2005) Microtectonics. Springer-Verlag, Berlin, 366p.
38 Ramsay, J.G. and Huber, M.I. (1987) The Techniques of Modern Structural Geology. vol. 2: Folds and Fractures, Academic Press, London, 700p.
39 Ree, J.-H., Kwon, S.-H., Park, Y., Kwon, S.-T. and Park, S.-H. (2001) Pretectonic and posttectonic emplacements of the granitoids in the south central Okcheon belt, South Korea: Implications for the timing of strike-slip shearing and thrusting. Tectonics, v.20, p.850-867. doi: 10.1029/2000tc001267   DOI
40 Sajeev, K., Jeong, J., Kwon, S., Kee, W.-S., Kim, S.W., Komiya, T., Itaya, T., Jung, H.-S. and Park, Y. (2010) High P-T granulite relicts from the Imjingang Belt, South Korea: tectonic significance. Gondwana Research, v.17, p.75-86. doi: 10.1016/j.gr.2009.07.001   DOI
41 Behrmann, J.H. and Mainprice, D. (1987) Deformation mechanism in a high temperature quartz-feldspar mylonite: evidence for superplastic flow in the lower continental crust. Tectonophysics, v.140, p.297-305. doi: 10.1016/0040-1951(87)90236-8   DOI
42 Simpson, C. (1985) Deformation of granitic rocks across the brittleductile transition. Journal of Structural Geology, v.7, p.503-511. doi: 10.1016/0191-8141(85)90023-9   DOI
43 Omori, S. and Isozaki, Y. (2011) Paleozoic Japan and the Eastern Extension of the collisional suture between the North and South China Cratons. Journal of Geography, v.120, p.40-51. doi: 10.5026/jgeography.120.40   DOI