Eos, Transactions American Geophysical Union

New software models thermodynamics of magmatic systems



A new software package, MELTS, is now available for modeling crystal-liquid equilibria in magmatic systems. MELTS is based on experimentally calibrated models for the thermodynamics of solution of magmatic liquids and solids [Ghiorso and Sack, 1994; Hirschmann and Ghiorso, 1994]. The package computes equilibrium phase assemblages—the compositions and proportions of coexisting liquids and solids—by direct minimization of the thermodynamic potential of the system [Ghiorso and Kelemen, 1987]. MELTS has a menu driven, interactive, graphical user interface and may be used to model a range of igneous processes including equilibrium or fractional crystallization of specified bulk compositions, crystallization paths under specified T-f02, total enthalpy, total entropy, or total volume constraints, and assimilation or magma mixing in evolving magmatic systems.