Sm-Nd isotopic signature and U-Pb shrimp zircon dating of the Cacheuta sub-basin, Cuyo basin, NW-Argentina

Abstract

The Cuyo Basin rift is located in the northwestern Mendoza Province (NW-Argentina), as part of the Argentine Precordillera. It is a Triassic basin which has a very dynamic evolution controlled by climatic and tectonic events during the geological time. Such events influenced directly the basin inception, geometry and depositional evolution, Ieading to correlation between strata in different regions to be a very difficuit task. The Cacheuta sub-basin consists in one of the most important depocenters of the Cuyo Basin, especially due to its economic potential in hydrocarbon exploration (Chebli et al., 2001). The Cuyo Basin displays a general NW-SE trend, mostly controlled by pre-existing structures (Ramos, 1992) (Fig. 1). The eastern limit of this basin coincides with an important suture generated in the Silurian through the amalgamation of the Cuyania Terrane to the southwestern margin of Gondwana. On the other hand, the western border is a structure that represents the Devonian accretion zone of the Chilenia and Cuyania terranes (Ramos & Kay, 1991).