Late Cretaceous stratigraphy and paleoceanographic evolution in the Great Australian Bight Basin based on results from IODP Site U1512

The Upper Cretaceous sequence at Site U1512 is notable for its lithologic uniformity. Burrow-mottled to massive claystone and silty claystone make up the majority of the almost 700 m section, while rare (n = 28) isolated, 2 to 21 cm thick medium to fine sandstone beds are a minor lithology. Macrofossils present include common inoceramids and rare occurrences of other bivalves and ammonites. Microfossils include common occurrences of calcareous nannofossils, agglutinated and calcareous benthic foraminifera, radiolaria and organic-walled dinoflagellate cysts as well as rare, small, surface dwelling planktonic foraminifera. Carbonate (<7%) and organic carbon (<1.5%) contents are low. Despite the lithologic uniformity, rhythmic alternations in the intensity of magnetic susceptibility and natural gamma radiation are well-resolved in much of the recovered section and continue through minor coring gaps (as documented by downhole logs). Data from Site U1512 provide new perspectives on the deep-water frontier region between Antarctica and Australia. (C) 2020 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.