Detrital zircon records of the Paleo-Mesoproterozoic rift-sag Tamandu? group in its type-section, Northern Quadril?tero Ferr?fero, Minas Gerais, Brazil.

The Quadril?tero Ferr?fero metallogenetic province is located in the southernmost portion of the S?o Francisco craton, SE Brazil. The Tamandu? and Cambotas ridges stand out topographically in the northeastern portion of Quadril?tero Ferr?fero and show NE-SW and N-S directions, respectively. Those ridges involve metasedimentary rocks of the Tamandu? Group bounded by a fault system. Due to stratigraphic and structural complexities, there is little consensus about the maximum sedimentation age and the stratigraphic position in which Tamandu? Group sediments were deposited. In this work, we took advantage of the excellent exposures in the Tamandu? and Cambotas ridges to present detailed stratigraphic observations combined with U-Pb zircon geochronological data from samples of different stratigraphic levels of Tamandu? Group. Furthermore, we provide U-Pb data from samples of the intrusive Pedra Formosa Suite that cut the whole Tamandu? sequence in the study area. Our observations showed that the Tamandu? Group represents a rift-sag basin-fill succession developed along the eastern border of the S?o Francisco paleoplate. The basal metaconglomerate and metasandstone package grades upward into marine metasandstone and phyllite. Detrital zircon obtained from the basal unit, Ant?nio dos Santos Formation, reveals maximum depositional ages between ca. 1981 and 1770 Ma. The upper succession, Cambotas Formation, shows a maximum depositional age from 1769 to 1740 Ma. The Pedra Formosa Suite shows zircons that crystallized at ca. 1740 Ma. The stratigraphic framework and the Orosirian-Statherian ages suggest a correlation with the first rifting event within the S?o Francisco paleoplate, the precursor of Paleo- to Mesoproterozoic Espinha?o basin