DOI: 10.1038/NGEO3050
论文题名: Dry Juan de Fuca slab revealed by quantification of water entering Cascadia subduction zone
作者: Canales J.P. ; Carbotte S.M. ; Nedimovic M.R. ; Carton H.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2017
卷: 10, 期: 11 起始页码: 864
结束页码: 870
语种: 英语
Scopus关键词: faulting
; Juan de Fuca plate
; lower crust
; lower mantle
; microtremor
; porewater
; seismicity
; slab
; subduction zone
; thermal structure
; water content
; Cascadia Margin
; Cascadia Subduction Zone
; Pacific Ocean
英文摘要: Water is carried by subducting slabs as a pore fluid and in structurally bound minerals, yet no comprehensive quantification of water content and how it is stored and distributed at depth within incoming plates exists for any segment of the global subduction system. Here we use seismic data to quantify the amount of pore and structurally bound water in the Juan de Fuca plate entering the Cascadia subduction zone. Specifically, we analyse these water reservoirs in the sediments, crust and lithospheric mantle, and their variations along the central Cascadia margin. We find that the Juan de Fuca lower crust and mantle are drier than at any other subducting plate, with most of the water stored in the sediments and upper crust. Variable but limited bend faulting along the margin limits slab access to water, and a warm thermal structure resulting from a thick sediment cover and young plate age prevents significant serpentinization of the mantle. The dryness of the lower crust and mantle indicates that fluids that facilitate episodic tremor and slip must be sourced from the subducted upper crust, and that decompression rather than hydrous melting must dominate arc magmatism in central Cascadia. Additionally, dry subducted lower crust and mantle can explain the low levels of intermediate-depth seismicity in the Juan de Fuca slab. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/105685
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, United States; Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; Department of Earth Sciences, Dalhousie University, Halifax, NS, Canada; Institut de Physique du Globe de Paris, Paris Cedex 05, France
Recommended Citation:
Canales J.P.,Carbotte S.M.,Nedimovic M.R.,et al. Dry Juan de Fuca slab revealed by quantification of water entering Cascadia subduction zone[J]. Nature Geoscience,2017-01-01,10(11)