Elastic anisotropy of FeSiO3 end-members of the perovskite and post-perovskite phases
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چکیده
[1] 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. Citation: Stackhouse, S., J. P. Brodholt, and G. D. Price (2006), Elastic anisotropy of FeSiO3 end-members of the perovskite and post-perovskite phases, Geophys. Res. Lett., 33, L01304, doi:10.1029/2005GL023887.
منابع مشابه
High temperature elastic anisotropy of the perovskite and post- perovskite polymorphs of Al2O3
[1] Finite temperature ab initio molecular dynamics calculations were performed to determine the high temperature elastic and seismic properties of the perovskite and post-perovskite phases of pure endmember Al2O3. The post-perovskite phase exhibits very large degrees of shear-wave splitting. The incorporation of a few mole percent of Al2O3 into MgSiO3 is predicted to have little effect on the ...
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