New accurate compression data for γ-FeSiO
Résumé
The equation of state for γ-FeSiO was determined by single-crystal X-ray diffraction up to 10.2GPa at room temperature. The pressure-volume data, measured at 10 different pressures, do not show any evidence of a phase transformation and were fit by a third-order Birch-Murnaghan equation of state. The following coefficients were refined simultaneously: =559.44(6)Å,=187.3(1.7) GPa, and '=5.5(4). This result implies that the Mg/Fe substitution along the γ-Fo-Fa join does not significantly affect the bulk modulus. The sample shows higher ' than other compositions along the Fo-Fa join, which generally have ' ∼ 4. Based on our results we can calculate the sound bulk velocity of γ-FeSiO up to the pressures of the Transition Zone. Due to the larger ' of γ-FeSiO, the difference in bulk sound velocity between the two end-members decreases with increasing pressure.
Domaines
Sciences de la Terre
Origine : Fichiers produits par l'(les) auteur(s)
Loading...