Contact - caused by proximity to hot igneous intrusions developing a metamorphic aureole (halo) - recrystalization and growth of new minerals depending on distance from heat source
Burial metamorphism - increased temperature as burial increases (i.e. follows on from diagenesis) - oriented fabric not developed because.......
Regional metamorphism - broad scale regional response to differential stress and increased temperatures - development of oriented textures and new mineral assemblages depending on PT conditions