气候变化领域集成服务门户(CCPortal): Seismic Moment Accumulation Response to Lateral Crustal Variations of the San Andreas Fault System

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DOI	10.1029/2020JB021208
	Seismic Moment Accumulation Response to Lateral Crustal Variations of the San Andreas Fault System
	Ward L.A.; Smith-Konter B.R.; Xu X.; Sandwell D.T.
发表日期	2021
ISSN	21699313
卷号	126 期号:4
英文摘要	Rheologic variations in the Earth's crust (like elastic plate thickness [EPT] or crustal rigidity) modulate the rate at which seismic moment accumulates for potentially hazardous faults of the San Andreas Fault System (SAFS). To quantify rates of seismic moment accumulation, Global Navigation Satellite Systems, and Interferometric Synthetic Aperture Radar data were used to constrain surface deformation rates of a four-dimensional viscoelastic deformation model that incorporates rheological variations spanning a 900 km section of the SAFS. Lateral variations in EPT, estimated from surface heat flow and seismic depth to the lithosphere-asthenosphere boundary, were converted to lateral variations in rigidity and then used to solve for seismic moment accumulation rates on 32 fault segments. We find a cluster of elevated seismic moment rates (11–20 × 1015 Nm year−1 km−1) along the main SAFS trace spanning the historical Mw 7.9 1857 Fort Tejon earthquake rupture length; present-day seismic moment magnitude on these segments ranges from Mw 7.2–7.6. We also find that the average plate thickness in the Salton Trough is reduced to only 60% of the regional average, which results in a ∼60% decrease in moment accumulation rate along the Imperial fault. Likewise, a 30% increase of average plate thickness results in at least a ∼30% increase in moment rate and even larger increases are identified in regions of complex plate heterogeneity. These results emphasize the importance of considering rheological variations when estimating seismic hazard, suggesting that meaningful changes in seismic moment accumulation are revealed when considering spatial variations in crustal rheology. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	4D earthquake cycle model; earthquake potential; San Andreas Fault System; seismic moment accumulation rate; variable rheology
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/187201
作者单位	Department of Earth Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States; Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States
推荐引用方式 GB/T 7714	Ward L.A.,Smith-Konter B.R.,Xu X.,et al. Seismic Moment Accumulation Response to Lateral Crustal Variations of the San Andreas Fault System[J],2021,126(4).
APA	Ward L.A.,Smith-Konter B.R.,Xu X.,&Sandwell D.T..(2021).Seismic Moment Accumulation Response to Lateral Crustal Variations of the San Andreas Fault System.Journal of Geophysical Research: Solid Earth,126(4).
MLA	Ward L.A.,et al."Seismic Moment Accumulation Response to Lateral Crustal Variations of the San Andreas Fault System".Journal of Geophysical Research: Solid Earth 126.4(2021).