Physics and Chemistry of Minerals

, Volume 19, Issue 6, pp 361–368 | Cite as

The effect of Fe on the crystal structure of wadsleyite β-(Mg1 − xFex)2SiO4, 0.00≤x≤0.40

  • Larry W. Finger
  • Robert M. Hazen
  • Jinmin Zhang
  • Jaidong Ko
  • Alexandra Navrotsky
Article

Abstract

Single crystals of five wadsleyite compositions, β-(Mg,Fe)2SiO4 with Fe/(Fe+Mg)=0.00, 0.08, 0.16, 0.25 and 0.40, have been synthesized at high temperature and pressure in a uniaxial, split-sphere apparatus. Crystal structures of these samples, determined by x-ray diffraction techniques, reveal that iron is significantly ordered: Fe is depleted in the M2 octahedron, while it is enriched in M1 and M3. The most iron-rich synthetic sample, which falls well outside previous estimates of wadsleyite stability, raises questions regarding published Mg2SiO4-Fe2SiO4 phase diagrams at transition zone conditions.

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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Larry W. Finger
    • 1
  • Robert M. Hazen
    • 1
  • Jinmin Zhang
    • 1
  • Jaidong Ko
    • 2
  • Alexandra Navrotsky
    • 3
  1. 1.Geophysical LaboratoryCarnegie Institution of WashingtonUSA
  2. 2.Department of Earth and Space SciencesState University of New YorkStony BrookUSA
  3. 3.Department of Geological and Geophysical SciencesPrinceton UniversityPrincetonUSA

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