Journal
GEOPHYSICAL RESEARCH LETTERS
Volume 42, Issue 6, Pages 1741-1749Publisher
AMER GEOPHYSICAL UNION
DOI: 10.1002/2014GL062888
Keywords
iron-bearing bridgmanite; thermoelasticity
Categories
Funding
- NSC [102-2112-M-008-001-MY3]
- State Key Development Program of Basic Research of China [2014CB845905]
- NSF of China [41274087]
- [NSF/EAR 1319368]
- [NSF/CAREER 1151738]
- Directorate For Geosciences
- Division Of Earth Sciences [1348066] Funding Source: National Science Foundation
- Division Of Earth Sciences
- Directorate For Geosciences [1319361] Funding Source: National Science Foundation
Ask authors/readers for more resources
We present local density approximation augmented by the Hubbard-type correction calculations of high-temperature elastic properties of bridgmanite with composition (Mg(1-x)Fex2+)SiO3 for 0 <= x <= 0.125. Results of elastic moduli and acoustic velocities for the Mg end-member (x=0) agree very well with the latest high-pressure and high-temperature experimental measurements. In the iron-bearing system, we focus particularly on the change in thermoelastic parameters across the state change that occurs in ferrous iron above similar to 30GPa, often attributed to a high-spin (HS) to intermediate-spin (IS) crossover but explained by first-principles calculations as a lateral displacement of substitutional iron in the perovskite cage. We show that the measured effect of this change on the equation of state of this system can be explained by the lateral displacement of substitutional iron and not by the HS to IS crossover. The calculated elastic properties of (Mg0.875Fe0.1252+)SiO3 along an adiabatic mantle geotherm somewhat overestimate longitudinal velocities but produce densities and shear velocities quite consistent with the Preliminary Reference Earth Model data throughout most of the lower mantle.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available