气候变化领域集成服务门户(CCPortal): Inverse Migration of Seismicity Quiescence During the 2019 Ridgecrest Sequence

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DOI	10.1029/2020JB020329
	Inverse Migration of Seismicity Quiescence During the 2019 Ridgecrest Sequence
	Marsan D.; Ross Z.E.
发表日期	2021
ISSN	21699313
卷号	126 期号:3
英文摘要	Seismicity quiescences are best observed during sequences with multiple mainshocks and often emerge with some delay after an initial phase of aftershock triggering. The mechanisms controlling this delay are poorly understood, due to a lack of systematic and precise estimation of the duration of the triggering phase which is made complicated by the rapidly changing magnitude of completeness after the mainshock. Here, we analyze how such a delayed quiescence developed during the 2019 Ridgecrest (California) sequence, using a refined earthquake data set obtained by template matching and relative relocation. A method that allows estimating the aftershock occurrence rate after correcting for the change in detection (completeness magnitude) is applied. We find that an immediate seismicity shutdown was triggered by the second (M7.1) mainshock at the tips of the north-east trending cross-cut fault that hosted most of the slip of the first (M6.4) mainshock. This shutdown progressed toward the central part of this fault over the following days. The overall shutdown of the aftershock sequence of the M6.4 by the M7.1 rupture is consistent with static Coulomb stress modeling. This inverse migration is a unique observation, best explained by an enhanced spatial stress change variability in this central part where the cross-cut fault intersects the main fault of the M7.1 shock, hence a strongly damaged zone there. This further confirms previous observations of an enhanced structural disorder in this central part of the cross fault, showing that structural disorder has a first-order control on the seismicity dynamics at the scale of days. © 2021. American Geophysical Union. All Rights Reserved.
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/187257
作者单位	ISTerre, Université Savoie Mont-Blanc, CNRS, IRD, IFSTTAR, Le Bourget-du-Lac, France; Seismological Laboratory, California Institute of Technology, Pasadena, CA, United States
推荐引用方式 GB/T 7714	Marsan D.,Ross Z.E.. Inverse Migration of Seismicity Quiescence During the 2019 Ridgecrest Sequence[J],2021,126(3).
APA	Marsan D.,&Ross Z.E..(2021).Inverse Migration of Seismicity Quiescence During the 2019 Ridgecrest Sequence.Journal of Geophysical Research: Solid Earth,126(3).
MLA	Marsan D.,et al."Inverse Migration of Seismicity Quiescence During the 2019 Ridgecrest Sequence".Journal of Geophysical Research: Solid Earth 126.3(2021).