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

• Published in: Gondwana Research
• Main Authors: MacLeod, K. G., White, L. T., Wainman, C. C., Martinez, M., Jones, M. M., Batenburg, S. J., Riquier, L., Haynes, S. J., Watkins, D. K., Bogus, K. A., Brumsack, H-J, Guerra, R. do Monte, Edgar, K. M., Edvardsen, T., Harry, D. L., Hasegawa, T., Hobbs, R. W., Huber, B. T., Jiang, T., Kuroda, J., Lee, E. Y., Li, Y-X, Maritati, A., O'Connor, L. K., Petrizzo, M. R., Quan, T. M., Richter, C., Tejada, M. L. G., Tagliaro, G., Wolfgring, E., Xu, Z.
• Format: Report
• Language: English
• Published: ELSEVIER 2020
• Subjects: Cretaceous greenhouse climate; Gondwana breakup; Cretaceous paleoceanography; Great Australian Bight; Australo-Antarctic rifting; Geology; Geosciences; Multidisciplinary; Antarctic; Antarc*; Antarctica; Planktonic foraminifera
• Online Access: http://ir.qdio.ac.cn/handle/337002/167675; http://ir.qdio.ac.cn/handle/337002/167676; https://doi.org/10.1016/j.gr.2020.01.009

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.