Elastic anisotropy of FeSiO3 end-members of the perovskite and post-perovskite phases -: art. no. L01304

被引:47
作者
Stackhouse, S [1 ]
Brodholt, JP [1 ]
Price, GD [1 ]
机构
[1] UCL, Dept Earth Sci, London WC1E 6BT, England
基金
英国自然环境研究理事会;
关键词
D O I
10.1029/2005GL023887
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The athermal elastic constants of the perovskite and post-perovskite polymorphs of pure end-member FeSiO3 were calculated from ab initio calculations. We predict that incorporating ten mole percent FeSiO3 together with four mole percent Al2O3 into MgSiO3 reduces the perovskite to post-perovskite phase transition pressure by 5 GPa. Small changes in the seismic properties of the post-perovskite phase due to the incorporation of iron and alumina are compatible with observations for the lower mantle. MgSiO3 post-perovskite enriched in fifty percent or more iron may be responsible for ultra-low velocity zones at the base of the mantle.
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页数:4
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共 39 条
[1]  
Anderson D., 1989, Theory of the Earth
[2]   Electronic transitions in perovskite:: Possible nonconvecting layers in the lower mantle [J].
Badro, J ;
Rueff, JP ;
Vankó, G ;
Monaco, G ;
Fiquet, G ;
Guyot, F .
SCIENCE, 2004, 305 (5682) :383-386
[3]   PROJECTOR AUGMENTED-WAVE METHOD [J].
BLOCHL, PE .
PHYSICAL REVIEW B, 1994, 50 (24) :17953-17979
[4]   Prediction of a new phase transition in Al2O3 at high pressures -: art. no. L06303 [J].
Caracas, R ;
Cohen, RE .
GEOPHYSICAL RESEARCH LETTERS, 2005, 32 (06) :1-4
[5]   Subducted banded iron formations as a source of ultralow-velocity zones at the core-mantle boundary [J].
Dobson, DP ;
Brodholt, JP .
NATURE, 2005, 434 (7031) :371-374
[6]   A VERY SLOW BASAL LAYER UNDERLYING LARGE-SCALE LOW-VELOCITY ANOMALIES IN THE LOWER MANTLE BENEATH THE PACIFIC - EVIDENCE FROM CORE PHASES [J].
GARNERO, EJ ;
HELMBERGER, DV .
PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 1995, 91 (1-3) :161-176
[7]   The elasticity of the MgSiO3 post-perovskite phase in the Earth's lowermost mantle [J].
Iitaka, T ;
Hirose, K ;
Kawamura, K ;
Murakami, M .
NATURE, 2004, 430 (6998) :442-445
[8]   A synchrotron Mossbauer spectroscopy study of (Mg,Fe)SiO3 perovskite up to 120 GPa [J].
Jackson, JM ;
Sturhahn, W ;
Shen, GY ;
Zhao, JY ;
Hu, MY ;
Errandonea, D ;
Bass, JD ;
Fei, YW .
AMERICAN MINERALOGIST, 2005, 90 (01) :199-205
[9]   Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set [J].
Kresse, G ;
Furthmuller, J .
PHYSICAL REVIEW B, 1996, 54 (16) :11169-11186
[10]   From ultrasoft pseudopotentials to the projector augmented-wave method [J].
Kresse, G ;
Joubert, D .
PHYSICAL REVIEW B, 1999, 59 (03) :1758-1775