(ESH) Reconstructing Surface Ocean Productivity and Bottom Water Oxygen Content for the Eastern Pacific Over the Past Several 100,000 Years

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9503669 Loubere Detailed quantitative analysis of surface ocean productivity and bottom water oxygen contend over the past 400,000 years is proposed using two cores from the eastern equatorial Pacific. Paleoproductivity estimates will be based on a new quantitative, benthic Foraminiferal transfer function constrained by qualitative proxies extracted from statistical analysis of combined planktonic and benthic Foraminiferal assemblages, accumulation rates of sedimentary components and accumulation rates of benthic Foraminifera. The deep water paleo-oxygen estimates will be based on a quantitative benthic Foraminiferal transfer function tested at this stage by seeking a coherent signal at coring locations positioned under different biological productivity regimes. The main objective of the paleoproductivity work will be generate quantitative estimates over a time period long enough to test the relationship of eastern equatorial Pacific productivity to global climate change. Also, the data can be used to examine a model of equatorial paleoproductivity in which changes along the equator are antithetical to those in the 5 to 10 degree latitude belts on either side of the equator. Finally, the data, combined with accumulation rates of terrigenous components, can be used to examine the 'iron hypothesis' for productivity enhancement. The main objective of the paleo-oxygen work will be to test for signal coherence at different coring locations and to test initial results showing paleo-oxygen minima corresponding to North Atlantic melt water pulses and to Heinrich events.