Early Pliocene extension controlling arc-volcanism at the main Andes of Río Negro, North Patagonian Andes (41°30´-42°S)

TOBAL, JONATHAN; ORTS, DARÍO; ROJAS VERA, EMILIO; RENDA, EMILIANO; FOLGUERA, ANDRÉS; RAMOS, VÍCTOR A.

Antofagasta

Congreso; XIII Congreso Geológico Chileno; 2012

The Andean sector between 41º and 43º S, from Bariloche to Esquel cities, has been uplifted in two main contractional episodes: The first occurred in pre-Oligocene times and a second and more important in the Late Miocene. These events are now exposed in the fold and thrust belt as areas of upper crustal deformation from the Andes to the foothills, fossilized by younger less deformed strata. In this work, a new Pliocene extensional episode that affected differentially this sector of the Patagonian Andes is postulated based on the evidence of normal faults and synrift packages in the Pliocene strata.