Australia cretaceous climate and tectonics: oceanic anoxic events and cooling within the l. cretaceous greenhouse at SHL

Aside from pioneering studies of the Antarctic Peninsula, Antarctica and the southern high-latitudes’ (SHL) Cretaceous paleoclimate history remains largely unresolved. IODP Leg 369 offers a unique opportunity to better understand the Late Cretaceous greenhouse climate state at SHL, oceanic anoxic events (OAEs) outside of traditionally studied basins, and paleoceanographic conditions off Australia’s S-SW margin during initial from Antarctica. A one year post-expedition research plan is presented with key components as follows: 1.) Geochemical analysis of core samples for initial marine osmium isotope ratios (trace metal) highly sensitive to relative changes in global hydrothermal and continental weathering rates associated with volcanism at the onset of OAE 2 (~94 Ma). 2.) Sediment geochemical analysis of bulk organic carbon isotope ratios (δ13C) for a global stratigraphic correlation tool to test whether Late Cretaceous sequence boundaries of the southern Australian margin are synchronous with other basins globally. 3.) Development of a floating astronomical time scale via detection of Milankovitch cycles in cored marine sediments recorded by geophysical well logs, to determine precise timing and possible forcing mechanisms of paleoceanographic circulation patterns and paleoclimate events of Australia’s southern margin.