Ferrous iron diffusion in ferro-periclase across the spin transition

Details Ferrous iron diffusion in ferro-periclase across the spin transition Ferrous iron diffusion in ferro-periclase across the spin transition

Feb 2011

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011e%26psl.302..393a&link_type=abstract

Earth and Planetary Science Letters, Volume 302, Issue 3-4, p. 393-402.

Physics

4

Scientific paper

We present first-principle calculations on absolute diffusion rates of high- and low-spin ferrous iron in ferro-periclase. The diffusivity of high- and low-spin iron depends on the physical conditions (pressure and temperature), iron concentration and the value of the chosen Hubbard U. We also find that low-spin iron swaps back to high-spin during migration. Our results show that throughout the Earth's lower mantle, iron diffuses at a faster rate than magnesium (up to an order of magnitude). Thus, the effect of the spin transition only has a small impact on the rheology of periclase in the Earth's mantle. Using reasonable vacancy concentrations, we find that ferro-periclase is much weaker than MgSiO3-perovskite throughout the mantle. We conclude, therefore, that ferro-periclase controls the viscosity of the mantle in regions where it becomes interconnected, such as regions of high strain around slabs or near plumes. At very high pressures, such as in Super-Earths, low-spin iron diffusion is expected to become much slower than magnesium, eventually making ferro-periclase more viscous than pure periclase.

Affiliated with

Also associated with

No associations

Rating

Ferrous iron diffusion in ferro-periclase across the spin transition does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ferrous iron diffusion in ferro-periclase across the spin transition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ferrous iron diffusion in ferro-periclase across the spin transition will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1119533