DOI: 10.1016/j.epsl.2017.10.014
Scopus记录号: 2-s2.0-85042148766
论文题名: Single-crystal elasticity of MgAl2O4-spinel up to 10.9 GPa and 1000 K: Implication for the velocity structure of the top upper mantle
作者: Duan Y. ; Li X. ; Sun N. ; Ni H. ; Tkachev S.N. ; Mao Z.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 481 起始页码: 41
结束页码: 47
语种: 英语
英文关键词: Brillouin scattering
; high pressure-temperature
; MgAl2O4-spinel
; single-crystal elasticity
; top upper mantle
; velocity
Scopus关键词: Brillouin scattering
; Crystal structure
; Elastic moduli
; Elasticity
; Pressure effects
; Silicate minerals
; Structural geology
; Velocity
; X ray diffraction
; Diamond-anvil cell
; High pressure
; MgAl2O4 spinels
; Pressure and temperature
; Pressure dependence
; Spinel peridotites
; Upper mantle
; Velocity structure
; Single crystals
英文摘要: The combined effect of pressure and temperature on the single-crystal elasticity of MgAl2O4-spinel has been studied using Brillouin scattering and X-ray diffraction up to 10.9 GPa and 1000 K in externally-heated diamond anvil cells. The obtained single-crystal elastic moduli of MgAl2O4-spinel at ambient conditions are consistent with literature values and follow a linear increase with pressure at high temperatures. More importantly, the pressure dependence of the elastic moduli at high temperatures is much smaller than that at 300 K, indicating a stronger temperature effect on the elastic moduli of MgAl2O4-spinel at high pressures. Our new results were applied to model the sound velocity of MgAl2O4-spinel at relevant pressure and temperature conditions of the top upper mantle, showing that MgAl2O4-spinel has the greatest velocity and the VP/VS ratio among major mantle minerals. We further modeled the velocity of spinel-peridotite at the top upper mantle. Varying the composition of spinel-peridotite can lead to up to 2.1% variation in VP and 1.3% in VS. The top upper mantle with greater VP and VS should contain more olivine and spinel but less orthopyroxene. The velocity of the top upper mantle is thus strongly correlated with the composition of the region. Our results are thus important in understanding the composition and velocity of the top upper mantle. © 2017 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/110178
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Laboratory of Seismology and Physics of Earth's Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; Center for Advanced Radiation Sources, University of Chicago, Chicago, IL, United States
Recommended Citation:
Duan Y.,Li X.,Sun N.,et al. Single-crystal elasticity of MgAl2O4-spinel up to 10.9 GPa and 1000 K: Implication for the velocity structure of the top upper mantle[J]. Earth and Planetary Science Letters,2018-01-01,481