P-V and T-V Equations of State of natural biotite: An in-situ high-pressure and high-temperature powder diffraction study, combined with Mössbauer spectroscopy
Articolo
Data di Pubblicazione:
2007
Citazione:
P-V and T-V Equations of State of natural biotite: An in-situ high-pressure and high-temperature powder diffraction study, combined with Mössbauer spectroscopy / A. PAVESE, N. CURETTI, V. DIELLA, D. LEVY, M. DAPIAGGI, U. RUSSO. - In: AMERICAN MINERALOGIST. - ISSN 0003-004X. - 92:7(2007), pp. 1158-1164.
Abstract:
The P-V and T-V equations of state of a natural biotite sample (Mg/Fe ratio ≈ 1) have been studied
using in-situ high-pressure (0.000111 GPa) synchrotron radiation powder diffraction at the European
Synchrotron Radiation Facilities (ESRF) in Grenoble, France, and in-situ high-temperature (298610
K) laboratory X-ray powder diffraction. A third-order Birch-Murnaghan model [V0 = 498.7(1) Å3,
measured value] provides the following elastic parameters: K0 = 49(1) GPa, K’ = 8.1(5). The volume
thermal expansion is satisfactorily described by a constant value resulting in 37(2) 106 K1. Mössbauer
spectroscopy proves that REDOX reactions have occurred upon heating, presumably 2(OH + Fe2+)
→ 2O2 + 2Fe3+ + H2
↑ and/or 4Fe2+ + 2OH + O2 → 4Fe3+ + 3O2 + H2O. On the basis of the elastic
and thermal parameters measured we have modeled the deformation contribution (Gdeform) to the Gibbs
energy. The third-order Birch-Murnaghan model with V0 Þ xed at its experimental value and the model
with reÞ ned V0 do not signiÞ cantly differ from one another in terms of Gdeform. A comparison based on
Gdeform between biotite and phlogopite shows a better compliance to P of the former, though balanced
in mineral reactions by a difference of molar volume, i.e., V0(biotite) > V0(phlogopite).
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
Biotite; High-pressure studies; High-temperature studies; P-T stability
Elenco autori:
A. PAVESE, N. CURETTI, V. DIELLA, D. LEVY, M. DAPIAGGI, U. RUSSO
Link alla scheda completa: