PTMAFIC - SOFTWARE FOR THERMOBAROMETRY AND ACTIVITY CALCULATIONS WITHMAFIC AND ULTRAMAFIC ASSEMBLAGES

PTMAFIC is a PC-compatible computer program for thermobarometric calcu lation in mafic and ultramafic rocks. The program includes 14 geotherm ometers and 11 geobarometers, each with up to ten calibrations chosen from all those published up to 199 1. For the principal minerals of th ese rocks (e.g., amphiboles, garnet, olivine, plagioclase, pyroxenes, spinels) PTMAFIC can provide stoichiometric parameters such as cation site allocations, mole fractions, and mole percents of the end-members and thermodynamic parameters such as Margules parameters (W), activit ies (a), and activity coefficients (gamma) according to different mode ls.