气候变化领域集成服务门户(CCPortal): Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust

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DOI	10.1038/s41561-021-00740-1
	Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust
	Guo H.; McGuire J.J.; Zhang H.
发表日期	2021
ISSN	17520894
起始页码	341
结束页码	348
卷号	14 期号:5
英文摘要	The unknown onshore extent of megathrust earthquake rupture in the Cascadia subduction zone represents a key uncertainty in earthquake hazard for the Pacific Northwest that is governed by the physical state and mechanical properties of the plate interface. The Cascadia plate interface is segmented into an interseismically locked zone located primarily offshore that is expected to rupture in large earthquakes, a region of aseismic slow slip at greater depth, and an intervening transition zone of uncertain rupture potential. Here we image the evolution of the ratio of seismic compressional to shear wave velocities from the locked zone to the transition zone, which is related to changes in fluid content of the plate boundary zone, using a dense onshore–offshore seismic dataset from southernmost Cascadia. The locked zone shows evidence of high fluid content implying a high porosity, yet the downdip transition zone shows an order of magnitude lower porosity. This strong variation is consistent with models that contain a ductile region between the earthquake rupture and slow slip zones that would inhibit onshore propagation of future large earthquake ruptures and hence reduce seismic hazard. © 2021, The Author(s), under exclusive licence to Springer Nature Limited.
英文关键词	autocorrelation; correlation; earthquake rupture; rheology; S-wave; seismic hazard; subduction zone; transition zone; Pacific Northwest; Cascadia
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/206902
作者单位	Laboratory of Seismology and Physics of Earth’s Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China; Department of Geoscience, University of Wisconsin-Madison, Madison, WI, United States; US Geological Survey, Moffett Field, CA, United States; CAS Center for Excellence in Deep Earth Science, Guangzhou, China; Mengcheng National Geophysical Observatory, University of Science and Technology of China, Hefei, China
推荐引用方式 GB/T 7714	Guo H.,McGuire J.J.,Zhang H.. Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust[J],2021,14(5).
APA	Guo H.,McGuire J.J.,&Zhang H..(2021).Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust.Nature Geoscience,14(5).
MLA	Guo H.,et al."Correlation of porosity variations and rheological transitions on the southern Cascadia megathrust".Nature Geoscience 14.5(2021).