Abstract
Back-arc rifting at the middle eastern continental margin of the Korean Peninsula took place in the early stage of separation of the SW Japan Arc from mainland Asia in the Cenozoic. As a result, the margin preserves structural elements of rifting seawards that include a narrow rift (Hupo Basin), a major syn-rift border fault (Hupo Fault), and an uplifted rift flank (Hupo Bank). We correlated current seismicity at the margin with the rifting structures and estimated the potential seismic hazards. The Hupo Basin, in its overall shape, is a half-graben created by back-tilting of the hanging wall toward the Hupo Fault. The trace of the Hupo Fault is composed of multiple segments arcuate seawards, suggesting nucleation of rift faults at multiple places. The Hupo Fault is vertical at a shallow depth, but hypocentral locations of earthquakes indicate that the Hupo Fault is listric down to the upper and lower crustal boundary. Stochastic estimations of the maximum possible magnitude of earthquakes at the margin encompassing the Hupo Basin and the Hupo Bank average to ML 5.86. The estimated b-value of 0.63 is lower than that in the Korean Peninsula, which may suggest the dominance of thrust faulting with a strike-slip (or oblique) component on the listric and lower dipping portions of the faults at the margin.
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modified from Kim et al. 2018). (a) Back-arc rifting. (b) Breakup, back-arc spreading, and clockwise rotation of the SW Japan Arc. SKP = South Korean Plateau, HF = Hupo Fault, and UB = Ulleung Basin
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References
Anderson JG, Wesnousky SG, Stirling MW (1996) Earthquake size as a function of fault slip rate. Bull Seismol Soc Am 86:638–690
Han M, Kim HJ, Kang SY, Kim KH, Yoon SH, Kyung JB (2019) Detection of microearthquakes and identification of their causative structures in the eastern offshore region of South Korea. Tectonophysics 750:36–44
Ingle Jr JC (1992) Subsidence pattern of the Japan Sea: stratigraphic evidence from ODP sites and onshore sections. In: Tamaki K, Suyehiro K, Allan J, McWilliams M (eds) Pro ODP Sci Res, vol 127/128, pp 1197–1218. Ocean Drilling Program, College Station
Jackson J, McKenzie D (1983) The geometrical evolution of normal fault systems. J Struct Geol 5:471–482
Jain A, Verma AK, Vishal V, Singh TN (2013) Numerical simulation of fault reactivation phenomenon. Arab J Geosci 6:3293–3302
Kang YA, Kim W, Kang TS (2012) Relocation of earthquakes beneath the East Sea of Korea: uncertainty of hypocentral parameters caused by refracted waves. Geosci J 17:173–182
Kijko A, Smit A, Sellevoll MA (2016) Estimation of earthquake hazard parameters from incomplete data files. Part III. Incorporation of uncertainty of earthquake-occurrence model. Bull Seismol Soc Am 106:1210–1222
Kim HJ, Lee GH, Jou HT, Cho HM et al (2007) Evolution of the eastern margin of Korea: constraints on the opening of the East Sea. Tectonophysics 436:37–55
Kim HJ, Lee GH, Choi DL, Jou HT et al (2015) Back-arc rifting in the Korea Plateau in the East Sea (Japan Sea) and the separation of the SW Japan Arc from the Korean margin. Tectonophysics 638:147–157
Kim HJ, Jou HT, Lee GH (2018) Neotectonics of the eastern Korean margin inferred from back-arc rifting structure. Ocean Sci J 53:601–609
Lee GH, Yoon Y, Nam BH, Lim H, Kim YS et al (2011) Structural evolution of the southwestern margin of the Ulleung Basin, East Sea (Japan Sea) and tectonic implications. Tectonophysics 502:293–307
Noh MH, Lee SK, Choi KR (2000) Minimum magnitude of earthquake catalog of Korea Meteorological Agency for the estimation of seismicity parameters. J Korean Geophys Soc 3:261–268
Prosser S (1993) Rift-related linked depositional systems and their seismic expression. In: Williams GD, Dobb A (eds) Tectonics and seismic sequence stratigraphy. Geological Society Special Publication No. 71, pp 35–66
Rosendahl BR (1987) Architecture of continental rifts with special reference to East Africa. Annu Rev Earth Planet Sci 15:445–503
Sheen DH (2015) Comparison of local magnitude scales in South Korea. J Geol Soc Kor 51:415–424
Wu YM, Chen S, Chao WA, Koulakov I (2018) Relationship between earthquake b-values and crustal stresses in a young orogenic belt. Geophys Res Lett 45:1832–1837. https://doi.org/10.1002/2017GL076694
Zheng Y, ShenW ZL, Yang Y et al (2011) Crust and uppermost mantle beneath the North China Craton, northeast China, and the Sea of Japan from ambient noise tomography. J Geophys Res 116:B12312. https://doi.org/10.1029/2011JB008637
Yoon SH, Chough SK (1995) Regional strike-slip in the eastern continental margin of Korea and its tectonic implications for the evolution of Ulleung Basin, East Sea (Japan Sea). Geol Soc Am Bull 107:83–97
Acknowledgements
This work was funded by the Korea Institute of Ocean Science and Technology (Grant PE99941). HJ Kim and DG Yoo was supported from the Ministry of Oceans and Fisheries of Korea for the projects “A sustainable research and development of Dokdo (Grant No. PG52911)” and “Exploration on submarine active faults in the southern East Sea (Grant NP 2018-018)”, respectively. HJ Kim appreciates Dr. A Kijko for providing the HA3 software and Dr. Y Zheng for the 3-D Vs model of the NE Asia. We thank H Moon (KIOST) for drawing figures.
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Moon, S., Kim, HJ., Kim, KH. et al. Correlation of seismicity with geologic structures at the middle eastern Korean margin in the East Sea (Japan Sea) and seismic hazard assessment. Mar Geophys Res 43, 15 (2022). https://doi.org/10.1007/s11001-022-09479-9
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DOI: https://doi.org/10.1007/s11001-022-09479-9