气候变化领域集成服务门户(CCPortal): A Double Difference Tomography Study of the Washington Forearc: Does Siletzia Control Crustal Seismicity?

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DOI	10.1029/2020JB019750
	A Double Difference Tomography Study of the Washington Forearc: Does Siletzia Control Crustal Seismicity?
	Merrill R.; Bostock M.G.; Peacock S.M.; Calvert A.J.; Christensen N.I.
发表日期	2020
ISSN	21699313
卷号	125 期号:10
英文摘要	We present new seismic tomography of the Washington forearc using a suite of manually picked regional earthquake phase arrivals. The recovery of similarly sampled P and S velocity permits the robust calculation of Poisson's ratio throughout the region. The seismological signature of Siletzia, an accreted oceanic plateau that crops out in Washington as the Crescent Formation, is evident in our models as a continuous high Poisson's ratio body that coincides with subsurface structures estimated from potential field maps. Relocated earthquakes preferentially locate in low Poisson's ratio regions in the forearc crust and, in particular, in a diffuse layer located at 15–25 km depth in the crust beneath relatively aseismic Siletzia. Our imaging of the Puget Sound is consistent with previous interpretations of the architecture of major faults and blocks, as evident by distinct Poisson's ratio signatures that distinguish sedimentary basins from mafic rocks of the Crescent Formation. We speculate that seismicity below the Puget Sound is promoted by slab-derived fluids that are localized beneath Siletzia as a result of intrinsic low vertical permeability. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	relocation; seismicity; seismogenesis; Siletzia; tomography; velocity model
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/187539
作者单位	Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC, Canada; Department of Earth Sciences, Simon Fraser University, Burnaby, BC, Canada
推荐引用方式 GB/T 7714	Merrill R.,Bostock M.G.,Peacock S.M.,et al. A Double Difference Tomography Study of the Washington Forearc: Does Siletzia Control Crustal Seismicity?[J],2020,125(10).
APA	Merrill R.,Bostock M.G.,Peacock S.M.,Calvert A.J.,&Christensen N.I..(2020).A Double Difference Tomography Study of the Washington Forearc: Does Siletzia Control Crustal Seismicity?.Journal of Geophysical Research: Solid Earth,125(10).
MLA	Merrill R.,et al."A Double Difference Tomography Study of the Washington Forearc: Does Siletzia Control Crustal Seismicity?".Journal of Geophysical Research: Solid Earth 125.10(2020).