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The end of the Neoproterozoic is punctuated by glacial deposition, but the chronology of these deposits is hindered presently by the paucity of geochronological data. Here, we present new radiometric dating for the basal Sete Lagoas cap carbonate deposits that overlie glacial units in the São Francisco craton. Six samples from aragonite-pseudomorph crystal-rich facies, showing pristine textures and constant 87Sr/86Sr ratios around 0.7075, yielded a Pb–Pb isochron age of 740 ± 22 Ma, which is interpreted as the depositional age for these remarkably preserved rocks. This age can be used to infer a low-to-moderate palaeolatitude of 20–30° for carbonate (and glacial) deposition. In addition, as it overlaps the ages obtained for the oldest Neoproterozoic glacial successions, our result reinforces the idea of a long-standing ‘Sturtian’ interval, suggesting that this event represents either different discrete glaciations or a protracted event encompassing almost 80 Ma. [ABSTRACT FROM AUTHOR]

The syn-orogenic Miocene deposits of the Patagonian Foreland System were the focus of numerous works in the latest years, due to their central role in the comprehension of the tectono-stratigraphy and tectonic evolution related to the Patagonian Andean growth. In this work we present a chronostratigraphic scheme based on magnetostratigraphy and U Pb geochronology for one of the syn-orogenic successions of the Patagonian Foreland System: the Paso del Sapo Basin. The sequence is constrained to an age of >14.9 to <11.6 Ma, establishing ages of >14.9–14.6 Ma for the basal alluvial systems of La Pava Formation, with mean sedimentation rates of 4.2 cm/kyr; of 14.6 to 12.8–12.7 Ma for the lacustrine - deltaic environments of the lower Collón Cura Formation, with sedimentation rates ranging from 1.6 to 26.0 cm/kyr; and of 12.8–12.7 to <11.6 Ma for the alluvial systems of the upper Collón Cura Formation, with mean sedimentation rates of 8.5 cm/kyr. Our results indicate a continuous contractional tectonic phase at least during this time span (>14.9 to <11.6 Ma), which implicates that the Patagonian Foreland System at these latitudes was synchronously deformed with the tectonic activity along the Andean region. • A chronostratigraphic scheme based on U/Pb geochronology and magnetostratigraphy is presented for a North Patagonian basin • Results indicates ages of >14.9 to <11.6 Ma for the synorogenic sequence • Our data suggest that the deformation in the foreland region was synchronic with the deformation in the Andean domain [ABSTRACT FROM AUTHOR]