Metamorphic Pressure-temp-time Paths

The subject of P-T-t paths in metamorphic petrology has become a widely taught part of the geology curriculum. P-T-t paths represent the "raison d'etre" of metamorphic petrology within the broader framework of tectonics and mountain building processes. The paths represent the dynamic database for documenting the interaction of tectonic and thermal processes at mid-to-deep crustal levels in orogenic belts of all ages and are, therefore, to tectonics and petrology what fossils are to sedimentary petrology and paleontology.