Thermoelasticity of Silicate Perovskite and Magnesiowüstite and Stratification of the Earth's Mantle
- 21 August 1992
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 257 (5073), 1099-1101
- https://doi.org/10.1126/science.257.5073.1099
Abstract
Analyses of x-ray-diffraction measurements on (Mg,Fe)SiO3 perovskite and (Mg,Fe)O magnesiowüstite at simultaneous high temperature and pressure are used to determine pressure-volume-temperature equations of state and thermoelastic properties of these lower mantle minerals. Detailed comparison with the seismically observed density and bulk sound velocity profiles of the lower mantle does not support models of this region that assume compositions identical to that of the upper mantle. The data are consistent with lower mantle compositions consisting of nearly pure perovskite (>85 percent), which would indicate that the Earth's mantle is compositionally, and by implication, dynamically stratified.Keywords
This publication has 28 references indexed in Scilit:
- Global mapping of topography on the 660-km discontinuityNature, 1992
- Effects of phase transions and possible compositional changes on the seismological structure near 650 km depthGeophysical Research Letters, 1991
- Crystal structure and thermal expansion of (Mg,Fe)SiO3 perovskiteGeophysical Research Letters, 1990
- Experimental petrology of the lower mantle: A natural peredottte taken to 54 GPAGeophysical Research Letters, 1990
- Constraints on lower mantle composition and temperature from density and bulk sound velocity profilesGeophysical Research Letters, 1990
- Synthesis and Equation of State of (Mg,Fe) SiO 3 Perovskite to Over 100 GigapascalsScience, 1987
- Transition region of the Earth's upper mantleNature, 1986
- Phase transitions and mantle discontinuitiesReviews of Geophysics, 1983
- Some geophysical constraints on the chemical composition of the earth's lower mantleEarth and Planetary Science Letters, 1983
- Preliminary reference Earth modelPhysics of the Earth and Planetary Interiors, 1981