Tectonic evolution of the late Paleozoic basement in western Patagonia region (Argentina-Chile)

MARCOS, PAULO; GONZÁLEZ, PABLO D.; RENDA, EMILIANO M.; ORIOLO, SEBASTIÁN; SUÁREZ, RODRIGO; VARELA, MARÍA E.; GREGORI, D.

Encuentro; Metamorphic Studies Group Meeting; 2021

Patagonia constitutes a vast area located in the southern extreme of the South American Continent, where the igneous-metamorphic basement presents a complex evolution during the Paleozoic. The oldest outcrops are in the northeastern region near the Atlantic Ocean and correspond to the Cambrian - Ordovician Orogens [1,2]. In contrast, its western region comprises basement units of Silurian ? Devonian ages, showing that orogen-development processes migrated towards the southwest of Patagonia [3,4,5]. The last widespread igneous-metamorphic events record theLate Paleozoic Gondwanide Orogeny and are extensively distributed along the Patagonia's boundaries [2,6,7,8]. However, in the western boundary of the Patagonian region, only a few P-T-t path reconstructions were made for the late Paleozoic metamorphic basement [6,7,9,10]. These evolutionary P-T-t models were linked with the subduction of the Proto-Pacific Ocean plate along an active continental margin in southwestern Gondwana. The present contribution aims to review the different geodynamic conditions of the western Patagonia region and establish their relationshipwith the paleotectonic evolution during the late Paleozoic times.