The offshore Uljin, Korea, earthquake sequence of April 2006: seismogenesis in the western margin of the Ulleung Basin

다국어 초록 (Multilingual Abstract)

An unusual earthquake sequence comprising 11events with magnitude range of ML 2.0 to 3.2 ocurred of the east-ern coast of the southern Korean Peninsula in April 2006. Sincethere is no obvious mainshock in this sequence unlike a typicalmainshock-aftershock sequence, the seismicity patern shows thecharacteristics of swarm behavior. Focal mechanism of the largestevent (ML 3.2) on Hypocenter relocations of nine events improve the epicenter loca-tions that fal within an area with a radius of about 0.7 km whiledepths are les well constrained with ranges of 1.6 km to 13.0 km.We propose that a swarm behavior of the sequence is closelyrelated to the marginal geometry of the Ulleung Basin and theregional stress regime. The fact that epicenters of the April 2006sequence are at the same transitional zone of continental to riftedcontinental crust as that of the 29 May 2004, Mw 5.1, earthquakeindicates that the Uleung Fault is seismically active.

참고문헌 (Reference)

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