Da Silva, CRS;
Karki, BB;
Stixrude, L;
Wentzcovitch, RM;
(1999)
Ab initio study of the elastic behavior of MgSiO3 ilmenite at high pressure.
Geophysical Research Letters
, 26
(7)
943 - 946.
10.1029/1999GL900149.
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Abstract
We investigate the athermal high pressure behavior of the elastic properties of MgSiO3 ilmenite up to 30 GPa using the ab initio pseudopotential method. Our results at zero pressure are in good agreement with single-crystal elasticity measurements. The elastic anisotropy is shown to decrease slightly under compression and hence to remain substantial (25 to 20% shear wave anisotropy and 16 to 10% longitudinal wave anisotropy) over the pressure regime studied. The directions of fastest and slowest wave propagation are found to change slightly with pressure as determined by the pressure dependence of c(14) and c(25). Comparisons with the elastic behavior of other deep transition zone phases such as ringwoodite and garnet show that ilmenite is likely to be the fastest and most anisotropic mineral in this region. Large contrasts (approximate to 10%) in velocities and densities between ilmenite and garnet are suggested to be significant for the interpretation of lateral structure in the transition zone.
Type: | Article |
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Title: | Ab initio study of the elastic behavior of MgSiO3 ilmenite at high pressure |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1029/1999GL900149 |
Publisher version: | http://dx.doi.org/10.1029/1999GL900149 |
Language: | English |
Additional information: | Copyright 1999 by the American Geophysical Union |
Keywords: | X-ray-diffraction, Mantle, Heterogeneity, Phase, Constants, Garnet, Model |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences |
URI: | https://discovery.ucl.ac.uk/id/eprint/86645 |
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