The oxygen fugacity at which graphite or diamond forms from carbonate-bearing melts in eclogitic rocks

@article{Stagno2015TheOF,
  title={The oxygen fugacity at which graphite or diamond forms from carbonate-bearing melts in eclogitic rocks},
  author={Vincenzo Stagno and Daniel J. Frost and Catherine A. McCammon and H. Mohseni and Yi Wei Fei},
  journal={Contributions to Mineralogy and Petrology},
  year={2015},
  volume={169},
  pages={1-18}
}
The oxygen fugacity (fO2) at which carbonate-bearing melts are reduced to either graphite or diamond in synthetic eclogite compositions has been measured in multi-anvil experiments performed at pressures between 3 and 7 GPa and temperatures between 800 and 1,300 °C using iron–iridium and iron–platinum alloys as sliding redox sensors. The determined oxygen fugacities buffered by the coexistence of elemental carbon and carbonate-bearing melt are approximately 1 log unit below thermodynamic… 
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CO2 content of andesitic melts at graphite-saturated upper mantle conditions with implications for redox state of oceanic basalt source regions and remobilization of reduced carbon from subducted eclogite
We have performed experiments to determine the effects of pressure, temperature and oxygen fugacity on the CO2 contents in nominally anhydrous andesitic melts at graphite saturation. The andesite
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Ab initio molecular dynamics calculations on a carbonate‐silicate‐metal melt were performed to study speciation and coordination changes as a function of pressure and temperature. We examine in
Carbon, carbides, carbonates and carbonatitic melts in the Earth's interior
  • V. Stagno
  • Geology
    Journal of the Geological Society
  • 2019
Over recent decades, many experimental studies have focused on the effect of CO2 on phase equilibria and melting behaviour of synthetic eclogites and peridotites as a function of pressure and
Redox state determination of eclogite xenoliths from Udachnaya kimberlite pipe (Siberian craton), with some implications for the graphite/diamond formation
The formation of diamonds within eclogitic rocks has been widely linked to the fate of carbon during subduction and, therefore, referred to conditions of pressure, temperature, and oxygen fugacity
Experimental quantification of vanadium partitioning between eclogitic minerals (garnet, clinopyroxene, rutile) and silicate melt as a function of temperature and oxygen fugacity
Vanadium is a multivalent element that may speciate as V2+; V3+; V4+ and V5+ in silicate and oxide phases. The relative abundance of V in planetary materials can be used as a proxy for oxygen
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