Early cretaceous magmatic activity in southeast Uruguay: trace element and Sr-Nd isotopic constraints - Lustrino, Michele; Gomes, Celso B.; Melluso, Leone; Morbidelli, Lucio; Muzio, Rossana; Ruberti, Excelso; Tassinari, Colombo Celso Gaeta (South American Symposium on Isotope Geology, 2003)