Contributions to Mineralogy and Petrology

, Volume 62, Issue 2, pp 129–139 | Cite as

Pyroxene thermometry in simple and complex systems

  • Peter R. A. Wells
Article

Abstract

Simple mixing models have been applied to ortho- and clinopyroxene solid solutions and a semi-empirical equation of state extracted from the available experimental data for the diopside-enstatite miscibility gap. This equation successfully reproduces the miscibility gap over a temperature range of 800 °C to 1700 °C and is apparently also applicable to aluminous pyroxenes in the system CaSiO3-MgSiO3-Al2O3. The effect of iron solubility in the pyroxenes has been calibrated empirically using most of the available experimental data for multicomponent pyroxenes. This semi-empirical model reproduces most of the experimental data within 70 °C. Temperatures calculated for naturally equilibrated Mg-rich two-pyroxene assemblages deviate markedly from those estimated using the thermometer of Wood and Banno (1973). These discrepancies can be attributed to large inaccuracies in the thermometer of Wood and Banno (1973) for Mg-rich compositions.

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Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • Peter R. A. Wells
    • 1
  1. 1.Department of Geology and MineralogyUniversity of OxfordOxfordEngland

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