4.7 Article

Sound velocities and density measurements of solid hcp-Fe and hcp-Fe-Si (9 wt.%) alloy at high pressure: Constraints on the Si abundance in the Earth's inner core

Journal

EARTH AND PLANETARY SCIENCE LETTERS
Volume 482, Issue -, Pages 446-453

Publisher

ELSEVIER SCIENCE BV
DOI: 10.1016/j.epsl.2017.11.043

Keywords

seismic wave velocities; iron; iron-silicon alloys; high pressure; high temperature; Earth's inner core

Funding

  1. Investissements d'Avenir programme [ANR-11-IDEX-0004-02]
  2. Carnegie Institution for Science
  3. NSF [EAR-1619868]
  4. Sorbonne Universites
  5. Division Of Earth Sciences
  6. Directorate For Geosciences [1619868] Funding Source: National Science Foundation

Ask authors/readers for more resources

We carried out sound velocity and density measurements on solid hcp-Fe and an hcp-Fe-Si alloy with 9 wt.% Si at 300 K up to similar to 170 and similar to 140 GPa, respectively. The results allow us to assess the density (rho) dependence of the compressional sound velocity (V-p) and of the shear sound velocity (V-s) for pure Fe and the Fe-Si alloy. The established V-p-rho and V-s-rho relations are used to address the effect of Si on the velocities in the Fe-FeSi system in the range of Si concentrations 0 to 9 wt.% applicable to the Earth's core. Assuming an ideal linear mixing model, velocities vary with respect to those of pure Fe by similar to+80 m/s for V-p and similar to-80 m/s for Vs for each wt.% of Si at the inner core density of 13 000 kg/m(3). The possible presence of Si in the inner core and the quantification of its amount strongly depend on anharmonic effects at high temperature and on actual core temperature. (C) 2017 Elsevier B.V. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available