Measured oxygen fugacities of the Angra dos Reis achondrite as a function of temperature

R. Brett; Huebner J. Stephen; M. Sato

doi:10.1016/0012-821x(77)90139-x

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Measured oxygen fugacities of the Angra dos Reis achondrite as a function of temperature

R. Brett·Huebner J. Stephen·M. Sato

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Abstract

Measurements of the oxygen fugacity (ƒO 2 ) as a function of temperature ( T ) were made on an interior bulk sample of the cumulate achondrite, Angra dos Reis. Data clustered between the ƒO 2 -T relationship of the iron-wüstite assemblage and 1.2 log atm units above iron-wüstite. Interpretation of the data indicates that, throughout most of the cooling history of the meteorite, ƒO 2 values were defined by equilibria involving iron-bearing species at values close to the ƒO 2 of the assemblage iron-wüstite. Measured ƒO 2 data are compatible with crystallization and cooling at pressures greater than 50 bars.

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R. Brett, Huebner J. Stephen, M. Sato. 1977. Measured oxygen fugacities of the Angra dos Reis achondrite as a function of temperature. https://doi.org/10.1016/0012-821x(77)90139-x

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