Ferric iron in mantle-derived pyroxenes and a new oxybarometer for the mantle

  title={Ferric iron in mantle-derived pyroxenes and a new oxybarometer for the mantle},
  author={Robert W. Luth and Dante Canil},
  journal={Contributions to Mineralogy and Petrology},
  • R. Luth, D. Canil
  • Published 1 February 1993
  • Geology
  • Contributions to Mineralogy and Petrology
AbstractFerric iron contents of coexisting ortho- and clinopyroxene from spinel lherzolite xenoliths were measured with Mössbauer spectroscopy and found to be significant. In orthopyroxene, the range in Fe3+/ΣFe is from 0.04 to 0.14; in clinopyroxene, the range is from 0.12 to 0.24. Reactions involving coexisting olivine, orthopyroxene, and clinopyroxene, where either the esseneite (CaFe3+ AlSiO6) or the acmite (NaFe3+Si2O6) component in the clinopyroxene is considered, are used to calculate… 
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