气候变化领域集成服务门户(CCPortal): Near-Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion

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DOI	10.1029/2019JB017638
	Near-Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion
	Beeler N.M.; McLaskey G.C.; Lockner D.; Kilgore B.
发表日期	2020
ISSN	21699313
卷号	125 期号:2
英文摘要	We compared near-fault velocity spectra recorded during laboratory experiments to that of natural earthquakes. We fractured crystalline rock samples at room temperature and intermediate confining pressure (50 MPa). Subsequent slip events were generated on the fracture surfaces under higher confinement (300 MPa). Velocity spectra from rock fracture resemble the inverse frequency (1/f) decay of natural earthquake velocity. This spectrum can be attributed to fault creation via seismic fracturing over a wide range of spatial scales. In contrast, subsequent slips on the rough fracture surfaces are depleted in high frequency energy and falloff approximately as 1/f2. The 1/f2 spectrum is more consistent with a slider-block model obeying static-kinetic friction than a natural earthquake. The depleted high frequency content precludes the rough fault experiments from being directly analogous to natural sources. The suppression of high frequencies may have resulted from two possible factors: (1) the presence of a well-developed shear zone and coseismic damping of the fault motion by dissipation within it or, in our favored interpretation, (2) a smaller amount of energy dissipated by shearing relative to the total energy release at elevated confining pressure. In context of the latter explanation, a unifying concept that applies to these experiments, earthquakes, ground motion, and models of complex radiated motion is that high frequency radiated energy is relatively enhanced when total energy release is nearly balanced within the source region by dissipative processes. This near-critical energy release condition can be accessed at low normal stress in laboratory experiments. Published 2019. This article is a US Government work and is in the public domain in the USA.
英文关键词	earthquake source; friction; rock failure
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/187977
作者单位	U.S. Geological Survey, Cascades Observatory, Vancouver, WA, United States; School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, United States; U.S. Geological Survey, Earthquake Science Center, Menlo Park, CA, United States
推荐引用方式 GB/T 7714	Beeler N.M.,McLaskey G.C.,Lockner D.,et al. Near-Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion[J],2020,125(2).
APA	Beeler N.M.,McLaskey G.C.,Lockner D.,&Kilgore B..(2020).Near-Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion.Journal of Geophysical Research: Solid Earth,125(2).
MLA	Beeler N.M.,et al."Near-Fault Velocity Spectra From Laboratory Failures and Their Relation to Natural Ground Motion".Journal of Geophysical Research: Solid Earth 125.2(2020).