Closing the mid-Eocene palaeoceanography and time scale gap and testing Eocene climate hypotheses with material and data from IODP Expedition 342 (Newfoundland)

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This proposal, as part of an international "Eocene stable isotope consortium", exploits the opportunity provided by newly drilled sediment drift deposits on the Southeast Newfoundland Ridge (IODP Exp. 342 Shipboard Scientists, 2012) to develop a refined, astronomically calibrated age model for the Eocene, that can then be applied to a newly generated coupled benthic and planktonic stable isotope reconstruction to address important questions about the North Atlantic ocean circulation, climate, and carbon cycle behaviour by detailing palaeoceanographic changes throughout the epoch. By doing so, this proposal seeks to revisit a suite of interrelated questions regarding the evolution the Eocene Earth System.Major objectives of this proposal are:1. Develop the first complete cyclostratigraphic age model for the Eocene based on a single locale. Close the "Eocene gap" and tie data into an absolute astrochronological age model; evaluate whether there is a relationship between dominant forcing response frequency and palaeoclimatic condition (presence of ice-sheets)2. Generate a high-resolution, astronomically tuned benthic and planktic foraminiferal (surface and thermocline) d13C and d18O time series for the Eocene (34-56 Ma), with a focus for this proposal to generate high resolution mixed layer and thermocline planktic stable isotope series within magnetochron C20r (~ca. 44.3-46.2 Ma Ma)3. Examine the magnitude (and sensitivity) of orbitally paced climate and carbon cycle dynamics across the Early to Late Eocene.4. Test hypotheses relating to the global nature of major Eocene carbon cycle events (Pälike et al., 2012), including the Equatorial Pacific Eocene-long deepening of the calcite compensation depth (CCD) and carbonate accumulation events (CAEs).The sedimentary successions from Expedition 342 are particularly useful to achieve these objectives because of continuous sedimentation throughout Eocene, with particularly high sedimentation rates in the middle to lower late Eocene, windows of excellent microfossil preservation, an excellent set of bio- and palaeomagnetic datums, and a key location to test hypotheses about Eocene deep water formation.