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The tectonic setting of the eastern margin of the Sino-Korean Block inferred from detrital zircon U–Pb age and Nd isotope composition of the Pyeongan Supergroup (upper Palaeozoic – Lower Triassic), Korea

Published online by Cambridge University Press:  20 November 2017

MUN GI KIM
Affiliation:
School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
YONG IL LEE*
Affiliation:
School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
TAEJIN CHOI
Affiliation:
Department of Energy and Resources Engineering, Chosun University, Gwangju 61542, Korea
YUJI ORIHASHI
Affiliation:
Earthquake Research Institute, The University of Tokyo, Tokyo 113-0032, Japan
*
Author for correspondence: [email protected]

Abstract

The upper Palaeozoic succession (Pyeongan Supergroup) in central eastern Korea is well correlated with the equivalent successions distributed in North China, suggestive of the Korean upper Palaeozoic being part of the Sino-Korean Block. Detrital zircon U–Pb ages and Sm–Nd isotope compositions of the Pyeongan Supergroup in the Samcheok coalfield of the Taebaeksan Basin were analysed. A single predominant zircon age peak at c. 1.9 Ga (> 70%) is marked in all sedimentary units, followed by varying amounts of minor late Palaeozoic grains (up to 30%). The rarity of Meso- to Neoproterozoic- and Silurian-aged zircons confirms that sediment influx from the South China and Qinling blocks was insignificant. The 2.0–1.8 Ga-dominated zircon age pattern and the Nd isotope composition (average εNd(0) = −15.5±4.0) of the Pyeongan Supergroup most closely reflect the signature of the Yeongnam Massif basements, which supports a previous hypothesis that the Pyeongan Supergroup was mostly derived from a palaeo-orogen located to the east–southeast. Relatively higher εNd(0) values (> −10.1) in the lowermost and the upper parts of the succession are closely matched by the increased occurrence of syn-depositional-aged zircons, which indicates considerable mixing of juvenile materials at c. 320 Ma and 260 Ma. Both arc-related magmatic events are interpreted to have been related to oceanic subduction, suggesting that the eastern margin of the Sino-Korean Block was an active continental margin during late Palaeozoic times.

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Original Articles
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Copyright © Cambridge University Press 2017 

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References

Arakawa, Y., Saito, Y. & Amakawa, H. 2000. Crustal development of the Hida belt, Japan: evidence from Nd–Sr isotopic and chemical characteristics of igneous and metamorphic rocks. Tectonophysics 328, 183204.Google Scholar
Bock, B., McLennan, S. M. & Hanson, G. N. 1994. Rare earth element redistribution and its effects on the neodymium isotope system in the Austin Glen Member of the Normanskill Formation, New York, USA. Geochimica et Cosmochimica Acta 58, 5245–53.Google Scholar
Chang, K.-H. & Zhao, X. 2012. North and South China suturing in the east end: what happened in Korean Peninsula? Gondwana Research 22, 493506.Google Scholar
Cheong, C. H. 1969. Stratigraphy and paleontology of the Samcheog Coalfield, Gangweondo, Korea (Ⅰ). Journal of the Geological Society of Korea 5, 1355.Google Scholar
Cheong, C. H. 1973. A paleontological study of the fusulinids from the Samcheog Coalfield. Journal of the Geological Society of Korea 9, 4788 (in Korean with English abstract).Google Scholar
Cheong, C.-S., Jo, H. J., Jeong, Y.-J., Park, C.-S. & Cho, M. 2016. Geochemical and Sr–Nd isotopic constraints on the petrogenesis of the Goesan monzodiorite pluton in the central Okcheon belt, Korea. Island Arc 25, 4354.Google Scholar
Cheong, C.-S., Kim, N., Kim, J., Yi, K., Jeong, Y.-J., Park, C.-S., Li, H.-K. & Cho, M. 2014. Petrogenesis of Late Permian sodic metagranitoids in southeastern Korea: SHRIMP zircon geochronology and elemental and Nd–Hf isotope geochemistry. Journal of Asian Earth Sciences 95, 228–42.Google Scholar
Cheong, C.-S., Yi, K., Kim, N., Lee, T.-H., Lee, S. R., Geng, J.-Z. & Li, H.-K. 2013. Tracking source materials of Phanerozoic granitoids in South Korea by zircon Hf isotopes. Terra Nova 25, 228–35.Google Scholar
Choi, D. K. & Kim, E. Y. 2006. Occurrence of Changshania (Trilobita, Cambrian) in the Taebaeksan Basin, Korea and its stratigraphic and paleogeographic significance. Palaeogeography, Palaeoclimatology, Palaeoecology 242, 343–54.Google Scholar
Choi, D. K., Kim, D. H. & Sohn, J. W. 2001. Ordovician trilobite faunas and depositional history of the Taebaeksan Basin, Korea: implications for palaeogeography. Alcheringa: An Australasian Journal of Palaeontology 25, 5368.Google Scholar
Choi, T., Lee, Y. I. & Orihashi, Y. 2016. Crustal growth history of the Korean Peninsula: constraints from detrital zircon ages in modern river sediments. Geoscience Frontiers 7, 707–14.Google Scholar
Chough, S. K., Kwon, S.-T., Ree, J.-H. & Choi, D. K. 2000. Tectonic and sedimentary evolution of the Korean peninsula: a review and new view. Earth-Science Reviews 52, 175235.Google Scholar
Chun, H. Y. 1985. Permo-Carboniferous plant fossils from the Samcheok coalfield, Gangweondo, Korea Part 1. Journal of Paleontological Society of Korea 1, 95122.Google Scholar
Chun, H. Y. 1987. Permo-Carboniferous plant fossils from the Samcheog coalfield, Gangweondo, Korea Part 2. Journal of Paleontological Society of Korea 3, 127.Google Scholar
Cope, T., Ritts, B. D., Darby, B. J., Fildani, A. & Graham, S. A. 2005. Late Paleozoic sedimentation on the Northern Margin of the North China Block: implications for regional tectonics and climate change. International Geology Review 47, 270–96.Google Scholar
Dan, W., Li, X.-H., Wang, Q., Wang, X.-C., Wyman, D. A. & Liu, Y. 2016. Phanerozoic amalgamation of the Alxa Block and North China Craton: evidence from Paleozoic granitoids, U–Pb geochronology and Sr–Nd–Pb–Hf–O isotope geochemistry. Gondwana Research 32, 105–21.Google Scholar
Darby, B. J. & Gehrels, G. 2006. Detrital zircon reference for the North China block. Journal of Asian Earth Sciences 26, 637–48.Google Scholar
Ding, L.-X., Ma, C.-Q., Li, J.-W., Robinson, P. T., Deng, X.-D., Zhang, C. & Xu, W.-C. 2011. Timing and genesis of the adakitic and shoshonitic intrusions in the Laoniushan complex, southern margin of the North China Craton: implications for post-collisional magmatism associated with the Qinling Orogen. Lithos 126, 212–32.Google Scholar
Doh, S.-J. & Piper, J. D. A. 1994. Palaeomagnetism of the (Upper Palaeozoic-Lower Mesozoic) Pyongan Supergroup, Korea: a Phanerozoic link with the North China Block. Geophysical Journal International 117, 850–63.Google Scholar
Domeier, M. & Torsvik, T. H. 2014. Plate tectonics in the late Paleozoic. Geoscience Frontiers 5, 303–50.Google Scholar
Dong, Y., Liu, X., Neubauer, F., Zhang, G., Tao, N., Zhang, Y., Zhang, X. & Li, W. 2013. Timing of Paleozoic amalgamation between the North China and South China Blocks: evidence from detrital zircon U–Pb ages. Tectonophysics 586, 173–91.Google Scholar
Dong, Y., Zhang, G., Neubauer, F., Liu, X., Genser, J. & Hauzenberger, C. 2011. Tectonic evolution of the Qinling orogen, China: review and synthesis. Journal of Asian Earth Sciences 41, 213–37.Google Scholar
Ehiro, M., Tsujimori, T., Tsukada, K. & Nuramkhaan, M. 2016. Palaeozoic basement and associated cover. In The Geology of Japan (eds Moreno, T., Wallis, S., Kojima, T. & Gibbons, W.), pp. 2560. London: Geological Society of London.Google Scholar
Hirata, T., Iizuka, T. & Orihashi, Y. 2005. Reduction of mercury background on ICP-mass spectrometry for in situ U–Pb age determinations of zircon samples. Journal of Analytical Atomic Spectrometry 20, 696701.Google Scholar
Horie, K., Yamashita, M., Hayasaka, Y., Katoh, Y., Tsutsumi, Y., Katsube, A., Hidaka, H., Kim, H. & Cho, M. 2010. Eoarchean–Paleoproterozoic zircon inheritance in Japanese Permo-Triassic granites (Unazuki area, Hida Metamorphic Complex): unearthing more old crust and identifying source terranes. Precambrian Research 183, 145–57.Google Scholar
Hoskin, P. W. O. & Black, L. P. 2000. Metamorphic zircon formation by solid-state recrystallization of protolith igneous zircon. Journal of Metamorphic Geology 18, 423–39.Google Scholar
Hu, L., Cawood, P. A., Du, Y., Xu, Y., Xu, W. & Huang, H. 2015a. Detrital records for Upper Permian–Lower Triassic succession in the Shiwandashan Basin, South China and implication for Permo-Triassic (Indosinian) orogeny. Journal of Asian Earth Sciences 98, 152–66.Google Scholar
Hu, L., Cawood, P. A., Du, Y., Yang, J. & Jiao, L. 2015b. Late Paleozoic to Early Mesozoic provenance record of Paleo-Pacific subduction beneath South China. Tectonics 34, 9861008.Google Scholar
Hu, L., Du, Y., Cawood, P. A., Xu, Y., Yu, W., Zhu, Y. & Yang, J. 2014. Drivers for late Paleozoic to early Mesozoic orogenesis in South China: Constraints from the sedimentary record. Tectonophysics 618, 107–20.Google Scholar
Ishiwatari, A. & Tsujimori, T. 2003. Paleozoic ophiolites and blueschists in Japan and Russian Primorye in the tectonic framework of East Asia: a synthesis. Island Arc 12, 190206.Google Scholar
Jeong, H. & Lee, Y. I. 2000. Late Cambrian biogeography: conodont bioprovinces from Korea. Palaeogeography, Palaeoclimatology, Palaeoecology 162, 119–36.Google Scholar
Jeong, H. & Lee, Y. I. 2004. Nd isotopic study of Upper Cambrian conodonts from Korea and implications for early Paleozoic paleogeography. Palaeogeography, Palaeoclimatology, Palaeoecology 212, 7794.Google Scholar
Jian, P., Liu, D., Kröner, A., Windley, B. F., Shi, Y., Zhang, W., Zhang, F., Miao, L., Zhang, L. & Tomurhuu, D. 2010. Evolution of a Permian intraoceanic arc–trench system in the Solonker suture zone, Central Asian Orogenic Belt, China and Mongolia. Lithos 118, 169–90.Google Scholar
Kim, H. M. 1971. Paleozoic and Mesozoic paleocurrents of the Danyang coalfield district, Korea. Journal of the Geological Society of Korea 7, 257–76.Google Scholar
Kim, J. H., Lee, Y. I., Li, M. & Bai, Z. 2001. Comparison of the Ordovician-Carboniferous boundary between Korea and NE China: implications for correlation and tectonic evolution. Gondwana Research 4, 3953.Google Scholar
Kim, H. S., Ree, J.-H. & Kim, J. 2012. Tectonometamorphic evolution of the Permo-Triassic Songrim (Indosinian) orogeny: evidence from the late Paleozoic Pyeongan Supergroup in the northeastern Taebaeksan Basin, South Korea. International Journal of Earth Sciences 101, 483–98.Google Scholar
Kim, H. S., Seo, B. & Yi, K. 2014. Medium temperature and lower pressure metamorphism and tectonic setting of the Pyeongan Supergroup in the Munkyeong Area. The Journal of the Petrological Society of Korea 23, 311–24 (in Korean in English abstract).Google Scholar
Korea Institute of Geoscience and Mineral Resources (KIGAM). 1979. Geological Atlas of the Samcheog Coalfield, 1: 25,000 and Geology of the Samcheog Coalfield (Explanatory text), edited.Google Scholar
Korea Institute of Geoscience and Mineral Resources (KIGAM). 1995. Geological Map of Korea (1: 1,000,000), edited.Google Scholar
Lee, Y. I. 1990. Absence of feldspar in Carboniferous Manhang (Samcheog Coalfield) and Yobong Sandstones, Korea. Journal of the Geological Society of Korea 26, 63–9.Google Scholar
Lee, Y. I. 2002. Provenance derived from the geochemistry of late Paleozoic–early Mesozoic mudrocks of the Pyeongan Supergroup, Korea. Sedimentary Geology 149, 219–35.Google Scholar
Lee, S.-R. & Cho, K.-O. 2012. Precambrian crustal evolution of the Korean Peninsula. The Journal of the Petrological Society of Korea 21, 89112 (in Korean with English abstract).Google Scholar
Lee, Y., Cho, M., Cheong, W. & Yi, K. 2014a. A massif-type (~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, 408–16.Google Scholar
Lee, S. R., Cho, M., Hwang, J.H., Lee, B.-J., Kim, Y.-B. & Kim, J. C. 2003. Crustal evolution of the Gyeonggi massif, South Korea: Nd isotopic evidence and implications for continental growths of East Asia. Precambrian Research 121, 2534.Google Scholar
Lee, Y. I., Choi, T., Lim, H. S. & Orihashi, Y. 2010. Detrital zircon geochronology of the Cretaceous Sindong Group, Southeast Korea: implications for depositional age and Early Cretaceous igneous activity. Island Arc 19, 647–58.Google Scholar
Lee, Y. I., Choi, T. & Orihashi, Y. 2012. Depositional ages of upper Pyeongan Supergroup strata in the Samcheok coalfield, eastern central Korea. Journal of the Geological Society of Korea 48, 93–9 (in Korean with English abstract).Google Scholar
Lee, S.-G., Kim, T.-K. & Lee, T.-J. 2011. Rare Earth Element, Sm–Nd and Rb–Sr age and its geochemical implication of leucogranite in the Deokgu Hot Spring Area, Yeongnam Massif, Korea. The Journal of the Petrological Society of Korea 20, 207–17 (in Korean in English abstract).Google Scholar
Lee, Y. I. & Lee, J. I. 2003. Paleozoic sedimentation and tectonics in Korea: a review. Island Arc 12, 162–79.Google Scholar
Lee, Y. I. & Lim, C. 1995. Provenance and compositional variance of the Carboniferous Manhang sandstones, central eastern Korea. Journal of the Geological Society of Korea 31, 637–52.Google Scholar
Lee, Y. I. & Sheen, D.-H. 1998. Detrital modes of the Pyeongan Supergroup (Late Carboniferous–Early Triassic) sandstones in the Samcheog coalfield, Korea: implications for provenance and tectonic setting. Sedimentary Geology 119, 219–38.Google Scholar
Lee, T.-H., Yi, K., Cheong, C.-S., Jeong, Y.-J., Kim, N. & Kim, M.-J. 2014b. SHRIMP U–Pb zircon geochronology and geochemistry of drill cores from the Pohang basin. The Journal of the Petrological Society of Korea 23, 167–85 (in Korean with English abstract).Google Scholar
Li, H.-Y., He, B., Xu, Y.-G. & Huang, X.-L. 2010. U–Pb and Hf isotope analyses of detrital zircons from Late Paleozoic sediments: insights into interactions of the North China Craton with surrounding plates. Journal of Asian Earth Sciences 39, 335–46.Google Scholar
Li, X.-H., Li, Z.-X., He, B., Li, W.-X., Li, Q.-L., Gao, Y. & Wang, X.-C. 2012. The Early Permian active continental margin and crustal growth of the Cathaysia Block: in situ U–Pb, Lu–Hf and O isotope analyses of detrital zircons. Chemical Geology 328, 195207.Google Scholar
Li, Z., Peng, S.-T., Xu, C.-W., Han, Y.-X. & Zhai, M.-G. 2009. U–Pb ages of the Paleozoic sandstone detrital zircons and their tectonic implications in the Tabeaksan basin, Korea. Acta Petrologica Sinica 25, 182–92 (in Chinese with English abstract).Google Scholar
Lu, S., Zhao, G., Wang, H. & Hao, G. 2008. Precambrian metamorphic basement and sedimentary cover of the North China Craton: a review. Precambrian Research 160, 7793.Google Scholar
Ludwig, K. R. 2003. User's Manual for Isoplot 3.00: A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center Special Publication no. 4.Google Scholar
Lv, D. & Chen, J. 2014. Depositional environments and sequence stratigraphy of the Late Carboniferous−Early Permian coal-bearing successions (Shandong Province, China): sequence development in an epicontinental basin. Journal of Asian Earth Sciences 79, 1630.Google Scholar
Ma, S., Meng, Q., Duan, L. & Wu, G. 2014. Reconstructing Late Paleozoic exhumation history of the Inner Mongolia Highland along the northern edge of the North China Craton. Journal of Asian Earth Sciences 87, 89101.Google Scholar
McDaniel, D. K., Hemming, S. R., McLennan, S. M. & Hanson, G. N. 1994. Resetting of neodymium isotopes and redistribution of REEs during sedimentary processes: the Early Proterozoic Chelmsford Formation, Sudbury Basin, Ontario, Canada. Geochimica et Cosmochimica Acta 58, 931–41.Google Scholar
McLennan, S. M. & Hemming, S. 1992. Samarium/neodymium elemental and isotopic systematics in sedimentary rocks. Geochimica et Cosmochimica Acta 56, 887–98.Google Scholar
Metcalfe, I. 2013. Gondwana dispersion and Asian accretion: tectonic and palaeogeographic evolution of eastern Tethys. Journal of Asian Earth Sciences 66, 133.Google Scholar
Park, S.-I. 1989. Conodont biostratigraphy of the Pyeongan Supergroup in Sabuk-Gohan area. Journal of the Geological Society of Korea 25, 192201 (in Korean with English abstract).Google Scholar
Park, S.-I. & Sun, Y. 2014. Neuropterid fossil plants from the basal part of the Middle Carboniferous Manhang Formation in the Taebaek area, Korea and their significance. Geosciences Journal 19, 1724.Google Scholar
Song, Y.-S., Lee, H.-S., Park, K.-H., Fitzsimons, I. C. W. & Cawood, P. A. 2015. Recognition of the Phanerozoic “young granite gneiss” in the central Yeongnam massif. Geosciences Journal 19, 116.Google Scholar
Stacey, J. S., & Kramers, J. D. 1975. Approximation of terrestrial lead isotope evolution by a two-stage model. Earth and Planetary Science Letters 26, 207–21.Google Scholar
Takahashi, Y., Cho, D.-L. & Kee, W.-S. 2010. Timing of mylonitization in the Funatsu Shear Zone within Hida Belt of southwest Japan: implications for correlation with the shear zones around the Ogcheon Belt in the Korean Peninsula. Gondwana Research 17, 102–15.Google Scholar
Tsutsumi, Y., Isozaki, Y. & Terabayashi, M. 2017. The most continent-sided occurrence of the Phanerozoic subduction-related orogens in SW Japan: zircon U–Pb dating of the Mizoguchi gneiss on the western foothill of Mt. Daisen volcano in Tottori. Journal of Asian Earth Sciences 145, 530–41.Google Scholar
Vermeesch, P. 2012. On the visualisation of detrital age distributions. Chemical Geology 312, 190–4.Google Scholar
Walker, J. D., Geissman, J. W., Bowring, S. A. & Babcock, L. E. 2012. Geologic Time Scale v. 4.0. Boulder, Colorado: Geological Society of America.Google Scholar
Wang, Q., Deng, J., Liu, X., Zhao, R. & Cai, S. 2016. Provenance of Late Carboniferous bauxite deposits in the North China Craton: new constraints on marginal arc construction and accretion processes. Gondwana Research 38, 8698.Google Scholar
Wiedenbeck, M., Alle, P., Corfu, F., Griffin, W. L., Meier, M., Oberli, F., Von Quadt, A., Roddick, J. C. & Spiegel, W. 1995. Three natural zircon standards for U–Th–Pb, Lu–Hf, trace element and REE analyses. Geostandards and Geoanalytical Research 19, 123.Google Scholar
Wu, Y.-B. & Zheng, Y.-F. 2013. Tectonic evolution of a composite collision orogen: an overview on the Qinling–Tongbai–Hong'an–Dabie–Sulu orogenic belt in central China. Gondwana Research 23, 1402–28.Google Scholar
Yang, J., Wu, F., Shao, J., Wilde, S., Xie, L. & Liu, X. 2006. Constraints on the timing of uplift of the Yanshan Fold and Thrust Belt, North China. Earth and Planetary Science Letters 246, 336–52.Google Scholar
Yi, K., Cheong, C.-S., Kim, J., Kim, N., Jeong, Y.-J. & Cho, M. 2012. Late Paleozoic to Early Mesozoic arc-related magmatism in southeastern Korea: SHRIMP zircon geochronology and geochemistry. Lithos 153, 129–41.Google Scholar
Yu, K.-M. & Lee, E.-S. 1993. Mineral assemblages and heavy minerals of sandstones from the Pyeongan Group in Taeback area, Korea. Journal of the Sedimentological Society of Japan 39, 6983.Google Scholar
Yu, K.-M., Lee, G.-H. & Boggs, S. 1997. Petrology of late Paleozoic-early Mesozoic Pyeongan Group sandstones, Gohan area, South Korea and its provenance and tectonic implications. Sedimentary Geology 109, 321–38.Google Scholar
Yuan, W. & Yang, Z. 2015. The Alashan Terrane did not amalgamate with North China block by the Late Permian: evidence from Carboniferous and Permian paleomagnetic results. Journal of Asian Earth Sciences 104, 145–59.Google Scholar
Zhai, M., Guo, J., Li, Z., Chen, D., Peng, P., Li, T., Hou, Q. & Fan, Q. 2007. Linking the Sulu UHP belt to the Korean Peninsula: evidence from eclogite, Precambrian basement, and Paleozoic sedimentary basins. Gondwana Research 12, 388403.Google Scholar
Zhai, M., Hu, B., Zhao, T., Peng, P. & Meng, Q. 2015. Late Paleoproterozoic–Neoproterozoic multi-rifting events in the North China Craton and their geological significance: a study advance and review. Tectonophysics 662, 153–66.Google Scholar
Zhang, J., Zhang, B. & Zhao, H. 2016. Timing of amalgamation of the Alxa Block and the North China Block: constraints based on detrital zircon U–Pb ages and sedimentologic and structural evidence. Tectonophysics 668–669, 6581.Google Scholar
Zhang, S.-H., Zhao, Y., Song, B., Hu, J.-M., Liu, S.-W., Yang, Y.-H., Chen, F.-K., Liu, X.-M. & Liu, J. 2009. Contrasting Late Carboniferous and Late Permian–Middle Triassic intrusive suites from the northern margin of the North China craton: geochronology, petrogenesis, and tectonic implications. Geological Society of America Bulletin 121, 181200.Google Scholar
Zhao, X., Mao, J., Ye, H., Liu, K. & Takahashi, Y. 2013a. New SHRIMP U–Pb zircon ages of granitic rocks in the Hida Belt, Japan: implications for tectonic correlation with Jiamushi massif. Island Arc 22, 508–21.Google Scholar
Zhao, Z., Wang, D.-H., Li, P.-G. & Lei, Z.-Y. 2013 b. Detrital zircon U–Pb geochronology of Dazhuyuan formation in northern Guizhou: implications for bauxite mineralization. Rock and Mineral Analysis 32, 166–73 (in Chinese with English abstract).Google Scholar
Zhou, J. B., & Wilde, S. A. 2013. The crustal accretion history and tectonic evolution of the NE China segment of the Central Asian Orogenic Belt. Gondwana Research 23, 1365–77.Google Scholar
Zhu, X.-Q., Zhu, W.-B., Ge, R.-F. & Wang, X. 2014. Late Paleozoic provenance shift in the south-central North China Craton: implications for tectonic evolution and crustal growth. Gondwana Research 25, 383400.Google Scholar
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