| DOI: | 10.1002/2015GL063446
|
| 论文题名: | Small shear modulus of cubic CaSiO3 perovskite |
| 作者: | Kawai K.; Tsuchiya T.
|
| 刊名: | Geophysical Research Letters
|
| ISSN: | 0094-8767
|
| EISSN: | 1944-8498
|
| 出版年: | 2015
|
| 卷: | 42, 期:8 | | 起始页码: | 2718
|
| 结束页码: | 2726
|
| 语种: | 英语
|
| 英文关键词: | Ca-perovskite
; elasticity
; first principles
; molecular dynamics
; shear modulus
|
| Scopus关键词: | Acoustics
; Calcium
; Calculations
; Elasticity
; Mean field theory
; Molecular dynamics
; Perovskite
; Shear strain
; Constant temperature
; Density functionals
; Earth's lower mantle
; First principles
; First-principles molecular dynamics methods
; Low-velocity anomaly
; New results
; Preliminary reference earth models
; Elastic moduli
; crystal structure
; elastic modulus
; elasticity
; lower mantle
; perovskite
; shear modulus
|
| 英文摘要: | Ca-perovskite (CaPv) is considered to be one of the most abundant minerals in the Earth's lower mantle (LM). Furthermore, previous static calculations and mean-field theory suggest that it has a much larger shear modulus than bridgmanite (MgPv). In this study, the elasticity of cubic CaPv was reinvestigated using the density functional constant-temperature first principles molecular dynamics method under the correct conditions to simulate its elasticity. Our new results clearly demonstrate that cubic CaPv has comparable bulk and slightly smaller shear moduli than Fe-bearing MgPv. This is because the boundary condition for the supercell used in this study allows for the rotational phonon motion of SiO6 octahedra under strain, which predominantly affects the decrease in C11 and C44. Acoustic wave velocities determined from the elastic moduli indicate that cubic CaPv has slower velocities and larger densities than Fe-bearing MgPv and preliminary reference Earth model in the LM. This suggests that if CaPv-rich material exists, it can accumulate in the lowermost LM and produce a seismically low-velocity anomaly. ©2015. American Geophysical Union. All Rights Reserved. |
| URL: | https://www.scopus.com/inward/record.uri?eid=2-s2.0-84929502549&doi=10.1002%2f2015GL063446&partnerID=40&md5=decea1591ce40cb1cfd7cae690290c40
|
| Citation statistics: |
|
| 资源类型: | 期刊论文
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/8383
|
| Appears in Collections: | 科学计划与规划
气候变化与战略
|
|
There are no files associated with this item.
|
|
作者单位: | Department of Earth Science and Astronomy, Graduate School of Arts and Sciences, University of Tokyo, Meguro, Japan
|
| Recommended Citation: | |
Kawai K.,Tsuchiya T.. Small shear modulus of cubic CaSiO3 perovskite[J]. Geophysical Research Letters,2015-01-01,42(8).
|
|
|