The (Na–Ca)amphibole–albite–chlorite–epidote–quartz geothermobarometer in the system S–A–F–M–C–N–H₂O. 2. Applications to metabasic rocks in different metamorphic settings

Abstract

ABSTRACT In order to illustrate different applications of the amphibole‐albite‐chlorite‐epidote‐quartz geothermobarometer, pressure‐temperature‐time ( P–T–t ) ± space ( P–T–t–s ) ± deformation ( P–T–t–d ) paths have been established from literature data. They are discussed as a function of the chemical, equilibrium and microstructural data available in each case, and compared with the conclusions already established by other methods. It is clear that it is necessary to know the relative chronology of the events (directions of zoning of minerals in successive microstructural positions) to establish precise P–T paths; this enables reconstruction of complex geodynamic histories. From this point of view, it is necessary to analyse the maximum possible number of minerals in a few well‐chosen metabasic rocks showing different generations of blastesis. The rocks should belong to different tectonic units to obtain the best overall picture of a metamorphic complex.