气候变化领域集成服务门户(CCPortal): Partitioned Fault Movement and Aftershock Triggering: Evidence for Fault Interactions During the 2017 Mw 5.4 Pohang Earthquake, South Korea

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DOI	10.1029/2020JB020005
	Partitioned Fault Movement and Aftershock Triggering: Evidence for Fault Interactions During the 2017 Mw 5.4 Pohang Earthquake, South Korea
	Son M.; Cho C.S.; Lee H.K.; Han M.; Shin J.S.; Kim K.; Kim S.
发表日期	2020
ISSN	21699313
卷号	125 期号:12
英文摘要	The 2017 Pohang earthquake (Mw 5.4) is the largest earthquake associated with fluid injection activities. We report new characteristics of the earthquake and propose a dislocation-type model explaining previously reported observations. We identify fault geometry by relocating the hypocenters of 1,132 events that occurred during the first 3 months and then resolve their source regions as the northern, central, and southern patches, based on event groups with similar waveforms. The spatial features of these similar waveform groups, in addition to our obtained source mechanisms, indicate that oblique contraction is prevalent in the source region: Reverse faulting dominates the southern fault and the deeper part of the central fault; near-parallel strike-slip sense controls the northern fault and the shallower part of the central fault. Furthermore, we identify a migrating aftershock pattern that matches the fluid diffusion process along both sides of the northern and central faults. This observation suggests the interconnection of the two faults, allowing fluid transport, and implies mainshock coseismic movement along the fault intersection. The coseismic slip of the fault intersection can induce a fault-valve process, which explains the aftershock migration pattern along the two intersecting faults. The proposed fault interaction accounts for the previously reported uplift between the two intersecting faults and successfully reproduces the non-double-couple mechanism of the mainshock. Our results raise the question of fluid-faulting interactions in the aftershock seismicity of the Pohang earthquake, and the complex fault movement provides insight into the rupture process that allowed the Pohang earthquake runaway. ©2020. The Authors.
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187479
作者单位	Earthquake Research Center, Korea Institute of Geoscience and Mineral Resources, Daejeon, South Korea; Earth and Environmental Science, Korea University, Seoul, South Korea
推荐引用方式 GB/T 7714	Son M.,Cho C.S.,Lee H.K.,et al. Partitioned Fault Movement and Aftershock Triggering: Evidence for Fault Interactions During the 2017 Mw 5.4 Pohang Earthquake, South Korea[J],2020,125(12).
APA	Son M..,Cho C.S..,Lee H.K..,Han M..,Shin J.S..,...&Kim S..(2020).Partitioned Fault Movement and Aftershock Triggering: Evidence for Fault Interactions During the 2017 Mw 5.4 Pohang Earthquake, South Korea.Journal of Geophysical Research: Solid Earth,125(12).
MLA	Son M.,et al."Partitioned Fault Movement and Aftershock Triggering: Evidence for Fault Interactions During the 2017 Mw 5.4 Pohang Earthquake, South Korea".Journal of Geophysical Research: Solid Earth 125.12(2020).