Reassessment of the Permian to Triassic Magmatism in the southwest of the Northpatagonian Massif: new cooling ages and mapping proposal

MARTÍNEZ DOPICO, C.; LOPEZ DE LUCHI, M.G.; WEMMER, K.; RAPALINI, A.E.

Viña del Mar

Congreso; INTERNATIONAL GEOLOGICAL CONGRESS ON THE SOUTHERN HEMISPHERE; 2013

Universidad Andrés Bello

Late Paleozoic to Triassic magmatism is an important event along the western margin of South America. Active margin and subsequent collisional events were envisaged for the Late Paleozoic tectonomagmatic evolution of northern Patagonia. Particularly, the Mamil Choique Granitoids (MCG) and related rocks have been interpreted as related to a postcollisional stage associated to the ca 330 Ma collision of the Deseado Massif (Pankhurst et al., 2006). In this contribution eight new K-Ar muscovite and biotite cooling ages are provided for six critical localities whose ages were not previously constrained such as the Loma Guacha hill to northeast of the Quintuleu stall, and the southeasternmost tip of the Sierra del Medio.