Anisotropy of akimotoite: A molecular dynamics study

doi:10.1016/j.pepi.2005.04.003

	Anisotropy of akimotoite: A molecular dynamics study
	Zhang, YG ; Zhao, DP ; Matsui, M
刊名	PHYSICS OF THE EARTH AND PLANETARY INTERIORS
	2005-08-15
卷号	151 期号:3-4 页码:309-319
关键词	Akimotoite Elastic Constants Anisotropy Mantle Transition Zone
ISSN号	0031-9201
DOI	10.1016/j.pepi.2005.04.003
文献子类	Article
英文摘要	Elastic constants of akimotoite at high-temperatures and pressures are calculated by using molecular dynamics simulations to study the anisotropic properties of akimotoite. We find that akimotoite becomes more anisotropic with increasing temperature but less with increasing pressure. On the (0 0 1) face, S-wave splitting and azimuthal anisotropy will occur simultaneously while the P-wave velocity remains almost constant. Polarization directions of the two S-waves are neither strictly perpendicular nor parallel to the crystallographic face. The polarization direction of the fast S-wave is more parallel with the plane than that of the slow S-wave for all wave propagation directions. On the (10 0) face, no S-wave splitting will occur for waves passing along the crystallographic c-axis, and the P-wave velocity along the axis is smaller than that in other directions. Polarization anisotropy changes its sign with the variation of wave propagation directions, giving rise to the dependence of the relative magnitude of V-SH and V-SV on the seismic wave propagation directions. We further calculate the anisotropic properties of a mineral assemblage containing ringwoodite, akimotoite, and Ca perovskite to infer the effect that akimotoite may have on the anisotropy of the lower portion of the mantle transition zone. We find that the mineral assemblage is much less anisotropic than akimotoite, but possesses many anisotropy features of akimotoite. Comparison of the anisotropy features with seismological observations indicates that a vertical flow direction is required in areas close to the subduction zones, which may be caused by the downward penetration of slabs to the lower mantle as well as upwelling of fluids and light materials in the mantle wedge associated with deep dehydration reactions of the slabs. (c) 2005 Elsevier B.V. All rights reserved.
WOS关键词	PACIFIC SUBDUCTION ZONES ; MANTLE TRANSITION ZONE ; X-RAY-DIFFRACTION ; HIGH-PRESSURE ; SEISMIC ANISOTROPY ; MGSIO3 ILMENITE ; HIGH-TEMPERATURES ; THERMAL EXPANSIVITY ; CASIO3 PEROVSKITE ; NORTHEAST CHINA
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000231078100009
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/65366]
专题	中国科学院地质与地球物理研究所
通讯作者	Zhang, YG
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 2.Ehime Univ, Geodynam Res Ctr, Matsuyama, Ehime 7908577, Japan 3.Univ Hyogo, Sch Sci, Kamigori, Hyogo 6781297, Japan
推荐引用方式 GB/T 7714	Zhang, YG,Zhao, DP,Matsui, M. Anisotropy of akimotoite: A molecular dynamics study[J]. PHYSICS OF THE EARTH AND PLANETARY INTERIORS,2005,151(3-4):309-319.
APA	Zhang, YG,Zhao, DP,&Matsui, M.(2005).Anisotropy of akimotoite: A molecular dynamics study.PHYSICS OF THE EARTH AND PLANETARY INTERIORS,151(3-4),309-319.
MLA	Zhang, YG,et al."Anisotropy of akimotoite: A molecular dynamics study".PHYSICS OF THE EARTH AND PLANETARY INTERIORS 151.3-4(2005):309-319.