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The Espinhaço Basin is one of the largest Precambrian intracratonic basins in the Brazilian Shield, and it comprises three tectonostratigraphic megasequences, i.e., the Lower, Middle, and Upper Espinhaço sequences, deposited from 1.8 to 1.68 Ga, 1.6 to 1.38 Ga, and 1.2 to 0.9 Ga, respectively. Each megasequence contain detrital materials derived from the denudation of basement and/or cover units and can be used to decipher the paleogeographic evolution of the São Francisco Craton, together with the vertical and lateral stratigraphic architecture. Sandstone compositions and detrital zircon U–Pb ages and Lu–Hf isotopes from the Middle and Upper Espinhaço sequences were investigated, in conjunction with stratigraphic data, to reveal distinct provenance patterns. Sandstones in the lower units of the Middle Espinhaço sequence were recycled from sedimentary sources and were found to contain Paleoproterozoic zircon grains, either juvenile or evolved from Mesoarchean or Neoarchean crustal sources. This pattern is succeeded by sandstones derived from recycled sedimentary sources that contain juvenile and remelted zircon grains formed in the Paleoarchean, Neoarchean, and Paleoproterozoic eras. The overlying units of the Middle and Upper Espinhaço sequences include significant inputs from Statherian and Calymmian zircon grains, in addition to the Archean and Paleoproterozoic grains. This points to both a stratigraphic inversion of the source area due to the denudation of Archean basement terrain in the lower sections and a change of provenance with the input of Statherian and Calymmian zircons in the upper sections. In addition, the ages and Hf isotopic compositions of zircon grains older than 1.8 Ga match the evolution of the continental crust within the São Francisco Craton. A possible chronocorrelation between the late Paleoproterozoic to Mesoproterozoic cratonic sequences in the Congo–São Francisco Craton and those sequences preserved within the Fennoscandian and Indian shields as well as in the North American, West Australian, and North China Cratons implies similar evolutions for these regions after ca. 1.8 Ga. Such a similarity is probably related to the evolution of the Columbia supercontinent and its transition to the Rodinia supercontinent. [ABSTRACT FROM AUTHOR]

Paleoproterozoic to Mesoproterozoic cratonic basins in the São Francisco Craton are classified into three megasequences: Statherian, Calymmian–early Ectasian, and Stenian–early Tonian sequences. The location, depositional age, and provenance of these sequences are reflected in their detrital zircon U–Pb age distributions. A minimum of five detrital zircon age distributions are distinguishable: i) the Archean and Rhyacian distribution, which is restricted to the Calymmian interval at Chapada Diamantina; ii) the Rhyacian distribution, which occurs in the Statherian, Calymmian, and Stenian intervals and generally precedes the Proterozoic distribution; iii) the Proterozoic distribution, which always succeeds the Rhyacian distribution and appears in the Brasília Belt and Southern Espinhaço; iv) the mixed Archean and Proterozoic distribution, restricted to the Stenian interval at the Southern Brasília Belt; and v) the Statherian distribution, which is present in the Statherian interval at Espinhaço Basin and is recycled into the Calymmian and Stenian intervals at Chapada Diamantina. Based on the Hf isotope compositions of the detrital zircons, most of the sequences are predominantly sourced from Archean juvenile terrains and from Archean and Paleoproterozoic evolved terrains. The exception is the Paranoá Group, western São Francisco Craton, whose positive ɛHf(t) values suggest juvenile Paleoproterozoic sources such as the Goiás Massif. The Archean zircons from Chapada Diamantina have Hf depleted mantle model ages ranging from Paleoarchean to Neoarchean and are mainly derived from the Gavião Block within northeastern São Francisco Craton. The model unify a dataset spanning hundreds of millions of years of the depositional record over a large area of central and eastern Brazil. The records will assist researchers in unraveling the sedimentary and tectonic history of the Archean and Paleoproterozoic continents from new data collected regionally and in other continents. [ABSTRACT FROM AUTHOR]

Abstract: The Itajaí Basin is a fault-bounded late- to post-orogenic basin deposited adjacent to the Dom Feliciano Belt in the state of Santa Catarina, Brazil. The basin is composed of alluvial-deltaic and platformal successions followed by a turbiditic complex and fan-delta deposits. U-Pb zircon dating of a tuff and five sandstone samples indicates a maximum depositional age of 563±3Ma for the intermediate and upper sections of the Itajaí Basin, and zircon dating of a rhyolite stock indicates a minimum depositional age of 549±4Ma. These dates are compatible with the previous assignment of an Ediacaran age to the sediments based on the discovery of Ediacara-type fossils such as Parvancorina, Charniodiscus, Cyclomedusa, and Aspidella. The U-Pb detrital zircon ages show a change in the sedimentary input from the base to the top. At the base, zircon grains from the Transamazonian and Brasiliano/Pan-African orogenic cycles occur as major sources with some Archean contribution. The upper section is dominated by Brasiliano/Pan-African zircon grains, most of which range in age from 824 to 770Ma and 656 to 563Ma. Pb and Sm-Nd whole rock isotope data suggest that the main source area for the basin infill was a reworked crust such as the Dom Feliciano Belt. We also present the regional correlation of the Itajaí Basin with the basins formed during the late stages of the SW Gondwana. [Copyright &y& Elsevier]