气候变化领域集成服务门户(CCPortal): Characteristics of Frequent Dynamic Triggering of Microearthquakes in Southern California

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DOI	10.1029/2020JB020820
	Characteristics of Frequent Dynamic Triggering of Microearthquakes in Southern California
	Fan W.; Barbour A.J.; Cochran E.S.; Lin G.
发表日期	2021
ISSN	21699313
卷号	126 期号:1
英文摘要	Dynamic triggering of earthquakes has been reported at various fault systems. The triggered earthquakes are thought to be caused either directly by dynamic stress changes due to the passing seismic waves, or indirectly by other nonlinear processes that are initiated by the passing waves. Distinguishing these physical mechanisms is difficult because of the general lack of high-resolution earthquake catalogs and robust means to quantitatively evaluate triggering responses, particularly, delayed responses. Here we use the high-resolution Quake Template Matching catalog in Southern California to systematically evaluate teleseismic dynamic triggering patterns in the San Jacinto Fault Zone and the Salton Sea Geothermal Field from 2008 to 2017. We develop a new statistical approach to identify triggered cases, finding that approximately 1 out of every 5 global Mw ≥ 6 earthquakes dynamically trigger microearthquakes in Southern California. The triggering responses include both instantaneous and delayed triggering, showing a highly heterogeneous pattern and indicating possible evolving triggering thresholds. We do not observe a clear peak ground velocity triggering threshold that can differentiate triggering earthquakes from nontriggering events, but there are subtle differences in the frequency content of the ground motion that may differentiate the earthquakes. In contrast to the depth distribution of background seismicity, the identified triggered earthquakes tend to concentrate at the edges of the seismogenic zones. Although instantaneously triggered earthquakes are likely a result of dynamic Coulomb stress changes, the cases of delayed-dynamic triggering are best explained by nonlinear triggering processes, including cyclic material fatigue, accelerated transient creep, and stochastic frictional heterogeneities. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	dynamic triggering; earthquakes; Salton Sea Geothermal Field; San Jacinto Fault Zone; Southern California
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/187420
作者单位	Scripps Institution of Oceanography, U.C. San Diego, La Jolla, CA, United States; Earthquake Science Center, U.S. Geological Survey, Moffett Field, CA, United States; Earthquake Science Center, U.S. Geological Survey, Pasadena, CA, United States; Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States
推荐引用方式 GB/T 7714	Fan W.,Barbour A.J.,Cochran E.S.,et al. Characteristics of Frequent Dynamic Triggering of Microearthquakes in Southern California[J],2021,126(1).
APA	Fan W.,Barbour A.J.,Cochran E.S.,&Lin G..(2021).Characteristics of Frequent Dynamic Triggering of Microearthquakes in Southern California.Journal of Geophysical Research: Solid Earth,126(1).
MLA	Fan W.,et al."Characteristics of Frequent Dynamic Triggering of Microearthquakes in Southern California".Journal of Geophysical Research: Solid Earth 126.1(2021).