a revised age for the granites of the central Somuncura Batholith, North Patagonian Massif

摘要: The age of the granites La Esperanza region Somuncura Batholith, North Patagonian Massif has been revised, based in part on RbSr whole-rock data obtained by reanalyzing samples from a previous study. new ages are 258 ± 15 Ma for Prieto Granodiorite and 259 16 Donosa Granite, both older plutonic complex, 239 4 Calvo younger volcano-plutonic Dos Lomas complex. initial 87Sr/86Sr ratios all range 0.7070–0.7076. probably correspond stratigraphically to Late Permian Early Triassic two complexes, respectively, consistent with traditional geologic interpretation. Together recently published Batholith Central Patagonia, it is clear that acidic associations northern Patagonia very latest Paleozoic Mesozoic age. They not obviously related terrane collision but Permo-Triassic acid magmatic province extends throughout central Andes preceded, or was associated with, early rifting Gondwana.