气候变化领域集成服务门户(CCPortal): Episodic stress and fluid pressure cycling in subducting oceanic crust during slow slip

CCPortal

DOI	10.1038/s41561-019-0367-x
	Episodic stress and fluid pressure cycling in subducting oceanic crust during slow slip
	Warren-Smith E.; Fry B.; Wallace L.; Chon E.; Henrys S.; Sheehan A.; Mochizuki K.; Schwartz S.; Webb S.; Lebedev S.
发表日期	2019
ISSN	17520894
卷号	12 期号:6
英文摘要	Slow slip events are part of a spectrum of aseismic processes that relieve tectonic stress on faults. Their spatial distribution in subduction zones has been linked to perturbations in fluid pressure within the megathrust shear zone and subducting oceanic crust. However, physical observations of temporal fluid pressure fluctuations through slow slip cycles remain elusive. Here, we use earthquake focal mechanisms recorded on an ocean-bottom seismic network to show that crustal stresses and fluid pressures within subducting oceanic crust evolve before and during slow slip events. Specifically, we observe that the retrieved stress ratio, which describes the relative magnitudes of the principal compressive stresses, systematically decreases before slow slip events in New Zealand’s northern Hikurangi subduction zone, and subsequently increases during the evolution of each slow slip event. We propose that these changes represent the accumulation and release of fluid pressure within overpressured subducting oceanic crust, the episodicity of which may influence the timing of slow slip event occurrence on subduction megathrusts. This work contributes an improved understanding of the physical driving forces underlying slow subduction earthquakes, and a potential means by which to monitor stress and fluid pressure accumulation in such regions. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	earthquake event; fluid pressure; focal mechanism; oceanic crust; pressure field; shear zone; slip; spatial distribution; subduction; Hikurangi; New Zealand; North Island; Northland
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/124652
作者单位	GNS Science, Lower Hutt, New Zealand; University of Texas Institute for Geophysics, Austin, TX, United States; University of Colorado at Boulder, Boulder, CO, United States; Earthquake Research Institute, University of Tokyo, Tokyo, Japan; University of California at Santa Cruz, Santa Cruz, CA, United States; Lamont-Doherty Earth Observatory, Palisades, NY, United States; Dublin Institute for Advanced Studies, Dublin, Ireland
推荐引用方式 GB/T 7714	Warren-Smith E.,Fry B.,Wallace L.,et al. Episodic stress and fluid pressure cycling in subducting oceanic crust during slow slip[J],2019,12(6).
APA	Warren-Smith E..,Fry B..,Wallace L..,Chon E..,Henrys S..,...&Lebedev S..(2019).Episodic stress and fluid pressure cycling in subducting oceanic crust during slow slip.Nature Geoscience,12(6).
MLA	Warren-Smith E.,et al."Episodic stress and fluid pressure cycling in subducting oceanic crust during slow slip".Nature Geoscience 12.6(2019).