New records of Late Neoproterozoic Acraman ejecta in the Officer Basin

Abstract

New occurrences of the Acraman impact ejecta layer were recently discovered in two drillholes, Giles 1 and Murnaroo 1, in the eastern Officer Basin, South Australia, using acritarch biostratigraphy and lithostratigraphy to predict the position. Fractured crystals were also observed in palynological preparations from drillhole SCYW 1a on the Stuart Shelf. These discoveries improve stratigraphic control of Late Neoproterozoic successions, especially in the eastern Officer Basin and will allow a test of the hypothesis that the Acraman impact event caused a global catastrophe.