Melting of Peridotites through to Granites: A Simple Thermodynamic Model in the System KNCFMASHTOCr

Abstract

A new set of thermodynamic models is presented for calculating phase relations in bulk compositions extending from peridotite to granite, from 0·001 to 70 kbar and from 650°C to peridotite liquidus temperatures, in the system K2O-Na2O-CaO-FeO-MgO-Al2O3-SiO2-H2O-TiO2-Fe2O3- Cr2O3 (KNCFMASHTOCr). The models may be used to calculate phase equilibria in partial melting of a large range of mantle and crustal compositions. They provide a good fit to experimental phase relation topologies and melt compositions across the compositional range of the model. Compared with the preliminary model of Jennings, E. S. & Holland, T. J. B. (2015) (A simple thermodynamic model for melting of peridotite in the s..