气候变化领域集成服务门户(CCPortal): Fluid transport and storage in the Cascadia forearc influenced by overriding plate lithology

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DOI	10.1038/s41561-022-00981-8
	Fluid transport and storage in the Cascadia forearc influenced by overriding plate lithology
	Egbert, Gary D.; Yang, Bo; Bedrosian, Paul A.; Key, Kerry; Livelybrooks, Dean W.; Schultz, Adam; Kelbert, Anna; Parris, Blake
发表日期	2022
ISSN	1752-0894
EISSN	1752-0908
起始页码	677
结束页码	+
卷号	15 期号:8 页码:17
英文摘要	Subduction of hydrated oceanic lithosphere can carry water deep into the Earth, with consequences for a range of tectonic and magmatic processes. Most of the fluid is released in the forearc where it plays a critical role in controlling the mechanical properties and seismic behaviour of the subduction megathrust. Here we present results from three-dimensional inversions of data from nearly 400 long-period magnetotelluric sites, including 64 offshore, to provide insights into the distribution of fluids in the forearc of the Cascadia subduction zone. We constrain the geometry of the electrically resistive Siletz terrane, a thickened section of oceanic crust accreted to North America in the Eocene, and the conductive accretionary complex underthrust along the margin. We find that fluids accumulate over timescales exceeding 1 My above the plate in metasedimentary units, while the mafic rocks of Siletzia remain dry. Fluid concentrations tend to peak at slab depths of 17.5 and 30 km, suggesting control by metamorphic processes, but also concentrate around the edges of Siletzia, suggesting that this mafic block is impermeable, with dehydration fluids escaping up-dip along the megathrust. Our results demonstrate that the lithology of the overriding crust can play a critical role in controlling fluid transport in a subduction zone. The lithology of the overriding plate plays a critical role in determining fluid transport in subduction zones, according to magnetotelluric imaging of the impact of the dry, mafic Siletzia terrane on fluids in the Cascadia subduction zone, North America.
学科领域	Geosciences, Multidisciplinary
语种	英语
WOS研究方向	Geology
WOS记录号	WOS:000825177800003
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/272503
作者单位	Oregon State University; Zhejiang University; United States Department of the Interior; United States Geological Survey; Columbia University; University of Oregon; United States Department of Energy (DOE); Pacific Northwest National Laboratory; United States Department of the Interior; United States Geological Survey
推荐引用方式 GB/T 7714	Egbert, Gary D.,Yang, Bo,Bedrosian, Paul A.,et al. Fluid transport and storage in the Cascadia forearc influenced by overriding plate lithology[J],2022,15(8):17.
APA	Egbert, Gary D..,Yang, Bo.,Bedrosian, Paul A..,Key, Kerry.,Livelybrooks, Dean W..,...&Parris, Blake.(2022).Fluid transport and storage in the Cascadia forearc influenced by overriding plate lithology.NATURE GEOSCIENCE,15(8),17.
MLA	Egbert, Gary D.,et al."Fluid transport and storage in the Cascadia forearc influenced by overriding plate lithology".NATURE GEOSCIENCE 15.8(2022):17.