Age and geochemistry of the Boucaut Volcanics in the Neoproterozoic Adelaide Rift Complex, South Australia

The Adelaide Rift Complex in South Australia records the break-up of Rodinia at a time of great climatic and biological evolution. The Boucaut Volcanics within the Neoproterozoic Adelaide Rift Complex of the Adelaide Superbasin lie at the base of the Burra Group, marking the boundary between the Burra Group and underlying Callanna Group. Despite their significance as one of the few volcanic units within the rift complex, there has been no robust age determination published for the Boucaut Volcanics. We use U-Pb zircon LA-ICP-MS data to determine an age of 788 +/- 6 Ma for the eruption of the bimodal Boucaut Volcanics. This has important implications for constraining the timing of stratigraphy within the Adelaide Superbasin. This also has far-reaching implications for plate tectonic reconstructions of Australia and Laurentia, and for correlating global isotope anomalies for the Neoproterozoic.

Automated summary

Using U-Pb zircon LA-ICP-MS data, an age of 788 +/- 6 Ma has been determined for the eruption of the bimodal Boucaut Volcanics within the Neoproterozoic Adelaide Rift Complex. This age determination is important for constraining the timing of stratigraphy within the Adelaide Superbasin and has implications for plate tectonic reconstructions of Australia and Laurentia, as well as for correlating global isotope anomalies for the Neoproterozoic.