DOI: 10.1038/ngeo2922
论文题名: The cold and relatively dry nature of mantle forearcs in subduction zones
作者: Abers G.A. ; Van Keken P.E. ; Hacker B.R.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2017
卷: 10, 期: 5 起始页码: 333
结束页码: 337
语种: 英语
Scopus关键词: earthquake event
; forearc basin
; island arc
; metamorphic rock
; plate boundary
; seismic data
; subduction zone
; tectonic wedge
英文摘要: Some of Earth's coldest mantle is found in subduction zones at the tip of the mantle wedge that lies between the subducting and overriding plates. This forearc mantle is isolated from the flow of hot material beneath the volcanic arc, and so is inferred to reach temperatures no more than 600 to 800 °C-conditions at which hydrous mantle minerals should be stable. The forearc mantle could therefore constitute a significant reservoir for water if sufficient water is released from the subducting slab into the mantle wedge. Such a reservoir could hydrate the plate interface and has been invoked to aid the genesis of megathrust earthquakes and slow slip events. Our synthesis of results from thermal models that simulate the conditions for subduction zones globally, however, indicates that dehydration of subducting plates is too slow over the life span of a typical subduction zone to hydrate the forearc mantle. Hot subduction zones, where slabs dehydrate rapidly, are an exception. The hottest, most buoyant forearcs are most likely to survive plate collisions and be exhumed to the surface, so probably dominate the metamorphic rock record. Analysis of global seismic data confirms the generally dry nature of mantle forearcs. We conclude that many subduction zones probably liberate insufficient water to hydrate the shallower plate boundary where great earthquakes and slow slip events nucleate. Thus, we suggest that it is solid-state processes and not hydration that leads to weakening of the plate interface in cold subduction zones. © 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/105785
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 Earth and Atmospheric Sciences, Cornell University, 2122 Snee Hall, Ithaca, NY, United States; Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington, DC, United States; Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA, United States
Recommended Citation:
Abers G.A.,Van Keken P.E.,Hacker B.R.. The cold and relatively dry nature of mantle forearcs in subduction zones[J]. Nature Geoscience,2017-01-01,10(5)