DOI: 10.1002/2015GL065142
论文题名: Variations in grain size and viscosity based on vacancy diffusion in minerals, seismic tomography, and geodynamically inferred mantle rheology
作者: Glišovic P. ; Forte A.M. ; Ammann M.W.
刊名: Geophysical Research Letters
ISSN: 0094-8598
EISSN: 1944-8329
出版年: 2015
卷: 42, 期: 15 起始页码: 6278
结束页码: 6286
语种: 英语
英文关键词: grain size
; mantle rheology
; seismic tomography
Scopus关键词: Elasticity
; Geodynamics
; Grain size and shape
; Seismic prospecting
; Seismographs
; Seismology
; Temperature distribution
; Viscosity
; Arrhenius temperature
; Deformation mechanism
; Distribution of grains
; Grain size
; Grain size variability
; Mantle rheology
; Seismic tomography
; Temperature and pressures
; Diffusion
; deformation mechanism
; diffusion
; geodynamics
; grain size
; high pressure
; high temperature
; mantle process
; mineral
; rheology
; seismic tomography
; viscosity
英文摘要: The effect of grain size on mantle viscosity is comparable to that of temperature and pressure. The current 3-D distribution of grain size in the mantle is, however, unknown. To explore the possible variability of grain size, we use the following: geodynamic inferences of effective viscosity, vacancy diffusion rates in upper mantle minerals and perovskite in the lower mantle, lateral variations in temperature derived from seismic images, and different geotherms. An important outcome of this modeling is a new mapping of lateral viscosity variations throughout the mantle. The corresponding 3-D variations in grain size are characterized by 2 orders of magnitude changes. We find a correlation between grain size variability in the mantle and absolute viscosity changes with depth. Our findings suggest that the traditional assumption of Arrhenius temperature dependence for vacancy diffusion in the lower mantle is not sufficient to constrain the deformation mechanisms that determine its effective bulk viscosity. ©2015. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940447527&doi=10.1002%2f2015GL065142&partnerID=40&md5=4e7ee85a04f3c9bc96fc0364c9dbe82c
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/8214
Appears in Collections: 科学计划与规划 气候变化与战略
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作者单位: GEOTOP, Université du Québec À Montréal, Montréal, QC, Canada
Recommended Citation:
Glišovic P.,Forte A.M.,Ammann M.W.. Variations in grain size and viscosity based on vacancy diffusion in minerals, seismic tomography, and geodynamically inferred mantle rheology[J]. Geophysical Research Letters,2015-01-01,42(15).