气候变化领域集成服务门户(CCPortal): Across-Fault Velocity Gradients and Slip Behavior of the San Andreas Fault Near Parkfield

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DOI	10.1029/2019GL084480
	Across-Fault Velocity Gradients and Slip Behavior of the San Andreas Fault Near Parkfield
	Piana Agostinetti N.; Giacomuzzi G.; Chiarabba C.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:1
英文摘要	A long-lasting question in earthquake physics is why slip on faults occurs as creep or dynamic rupture. We compute passive measurements of the seismic P wave velocity gradient across the San Andreas Fault near Parkfield, where this transition of slip mode occurs at a scale of a few kilometers. Unbiased measurements are obtained through the application of a new Bayesian local earthquake tomographic code that avoids the imposition of any user-defined, initial velocity-contrast across the fault, or any damping scheme that may cause biased amplitude in retrieved seismic velocities. We observe that across-fault velocity gradients correlate with the slip behavior of the fault. The P wave velocity contrast decays from 20% in the fault section that experience dynamic rupture to 4% in the creeping section, suggesting that rapid change of material properties and attitude to sustain supra-hydrostatic fluid pressure are conditions for development of dynamic rupture. Low Vp and high Vp/Vs suggest that fault rheology at shallow depth is conversely controlled by low frictional strength material. © 2019. The Authors.
英文关键词	Acoustic wave velocity; Earthquakes; Elasticity; Seismic waves; Strike-slip faults; Tomography; Wave propagation; Earthquake physics; Frictional strength; Initial velocities; Non linear; Passive measurements; Seismic velocities; Slip behavior; Velocity gradients; Fault slips; amplitude; earthquake event; earthquake rupture; fault; fluid pressure; P-wave; rheology; San Andreas Fault; seismic wave; wave velocity; California; Parkfield; United States
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170883
作者单位	Department of Geodynamics and Sedimentology, University of Wien, Wien, Austria; Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy
推荐引用方式 GB/T 7714	Piana Agostinetti N.,Giacomuzzi G.,Chiarabba C.. Across-Fault Velocity Gradients and Slip Behavior of the San Andreas Fault Near Parkfield[J],2020,47(1).
APA	Piana Agostinetti N.,Giacomuzzi G.,&Chiarabba C..(2020).Across-Fault Velocity Gradients and Slip Behavior of the San Andreas Fault Near Parkfield.Geophysical Research Letters,47(1).
MLA	Piana Agostinetti N.,et al."Across-Fault Velocity Gradients and Slip Behavior of the San Andreas Fault Near Parkfield".Geophysical Research Letters 47.1(2020).