The Austral-Magallanes and Malvinas basins, located at the southern end of the South American continent, limit to the west with the Andean volcanic arc, to the east with the Malvinas (Falkland) islands, and are separated by the Rio Chico High, a southern extension of the Deseado Massif. These basins were originated in the Mesozoic and are associated with a generalized rifting episode that affected Patagonia in the Early-Middle Jurassic, characterized by profuse volcanism (Chon Aike Magmatic Province, Tobífera Series). Since the Late Jurassic-Early Cretaceous, these basins went into a passive margin phase, with the onset of deposition of the transgressive sandstones of the Springhill Formation (main reservoir unit across the study area). This study integrates U-Pb radiometric dating on detrital zircons of the Springhill Formation recovered from six drilling cuttings samples from hydrocarbon exploration wells in the Austral basin and six core samples from the Malvinas basin. The objective was to determine maximum deposition ages, and to characterize sediment provenance to better understand the participation of different sediment provenance areas and the contemporaneous volcanic arc. The external morphological analysis of the zircon grains highlighted differences between both basins. Idiomorphic and prismatic zircons (of volcanic origin) predominate in the Austral basin, while in Malvinas rounded and sub-rounded zircons are more common and were related to a larger degree of reworking and a different source. Regarding provenance, the histogram pattern of U-Pb ages for the Springhill Formation in the Malvinas basin shows dominance of Mesoproterozoic and Neoproterozoic-Cambrian sources related to the Deseado Massif and Rio Chico High. In the Austral-Magallanes basin Neoproterozoic-Cambrian zircons dominate while Mesoproterozoic zircons are absent; this was interpreted as produced by a more local source in Tierra del Fuego. Jurassic Chon Aike sources are present in both sets, as Springhill Formation regionally overlies Tobifera Series (synrift volcanism). Despite the scarcity of contemporaneous Andean volcanic arc-related zircons in the Springhill Formation, it was possible to determine Tithonian to Hauterivian maximum ages of deposition.