geothermobarometry of al2sio5-bearing metapelites in the ardara aureole, nw ireland: an implication for p-t stability field of aluminium silicate polymorphs

andalusite, kyanite and sillimanite occur in well-defined zones in the ardara aureole, nwireland. temperature and pressure conditions of the al2sio5-bearing pelites in this aureole wereestimated using ten different calibrations of garnet-biotite thermometry and five calibrations of garnetplagioclase-al2sio5-quartz barometry. the different calibrations provide different estimates oftemperature and pressure. however, using the most recent, and the best reversed experimental data givetemperatures varying from 510 to 605 ºc, and a pressure of around 4 kbar across the ardara aureole. thecalculated temperatures for the analyzed samples are compared with published andalusite=sillimaniteequilibria, and these equilibria are evaluated in the ardara aureole.