collision zone 6 microplate Argentina 4 Gondwana 4 Sierras Pampeanas 4 argon-argon dating 4 crustal shortening 4 exhumation 4 shear zone 4 Albite-amphibolite facies 2 Anatolia 2 Block rotations 2 Chile 2 Collision zone 2 Collisional 2 Convergent margin 2 Deformation 2 Ductile shear zone 2 Fission track (zircon) 2 Garnet 2 Geothermobarometry 2 K-Ar system 2 La Rioja [Argentina] 2 Lower crust 2 Lu-Hf system 2 Mica 2 NW Argentina 2 Ordovician 2 Paleomagnetism 2 Paleozoic 2