Petrology of the Ordovician I- and S-type granitoids of the NE sector of the North Patagonian Massif

Abstract

Ordovician granitoids of the NE sector of the North Patagonian Massif are known as the Valcheta Pluton which intrudes the Nahuel Niyeu Formation and as the Punta Sierra Plutonic Complex which intrude the late Cambrian El Jagüelito Formation nearby Sierra Grande town and Hiparsa Mine. Moreover, around Gonzalito Mine, Ordovician granites and granodiorite orthogneisses are encompassed in the Mina Gonzalito Metamorphic Complex (Varela et al. 2011, among others). The aim of this contribution is to present an advance of an in progress major and trace elements, and Sr-Nd data study of the Ordovician magmatism. A total of 36 chemical analyses were considered. Sampling strategy involved well recorded- Ordovician granite localities in Valcheta, Arroyo Salado and Punta Sierra. These results were combined with geochemical data published by Busteros et al. (1998), Pankhurst et al. (2006), and Gozálvez (2009).