Detrital zircon ages from the Paleoproterozoic Tanque Novo–Ipirá Complex, Itabuna–Salvador–Curaçá Orogen, northern São Francisco Craton, Brazil: records from the Kenorland and Columbia supercontinents

The Tanque Novo–Ipirá Complex is an ultra-high-temperature metavolcano-sedimentary succession located in the northern portion of the Itabuna–Salvador–Curaçá Orogen, in the São Francisco Craton, but little is known about the provenance and tectonic significance of these rocks. The Tanque Novo–Ipirá Complex is mostly composed of granulite facies paragneiss containing cordierite, sapphirine, orthopyroxene, clinopyroxene, spinel, sillimanite, garnet and biotite, along with calc-silicate rocks and kinzigite. Although previously interpreted as an Archean sedimentary succession, new U–Pb (LA-SF-ICP-MS) data on detrital zircons show that the sedimentary units were deposited during the Rhyacian. From all detrital grains, the age range 2800–2400 Ma is the most abundant, with a peak around 2580 Ma. The second highest age concentration lies in the 2260–1900 Ma cluster, followed by the 2450–2260 and >2690 Ma age ranges. The U–Pb zircon age for an amphibole quartz–feldspar gneiss from the Tanque Novo Complex is 2127 ± 49 Ma, while two metagabbros intrusive into this gneiss yielded an age of 2096 ± 9 Ma. These results suggest that the metasedimentary succession of the Tanque Novo–Ipirá Complex was deposited between 2120 and 2095 Ma in a foreland to collisional tectonic setting, with implications for understanding the earliest collision stage of the Rhyacian–Orosirian São Francisco–Congo Orogeny in the Columbia Supercontinent.