Late Cretaceous climatic change in a mid latitude setting (Mississippi, USA): a multiproxy palaeoenvironmental study

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Late Cretaceous climate studies tend to focus on short intervals of relatively rapid change, e.g. the Oceanic Anoxic Event 2, and the Maastrichtian climate oscillations. Consequently, the long-term context of such change is poorly understood. The objective of my proposed study is to record climate change through the entire Campanian-Maastrichtian, and to determine the longer-term changes that led up to climatic instability in the Maastrichtian. I will investigate this by using well-preserved material from a corehole (Evans Shuqualak core, Mississippi) that provides a complete shelfal, mid-latitude sedimentary record. High-resolution measurements of TEX86 (as a proxy for surface-water palaeo-temperature) shall form the backbone to the interpretations of the Campanian–Maastrichtian climate. Bulk rock stable isotopes (δ13C, δ18O) as well as stable isotopes and Sr/Ca-ratios from single species coccolith calcite, shall be measured to provide an insight into other environmental parameters (e.g. C-cycling, photic zone nutrient load). Abundance counts and morphometric measurements of key cal-careous nannofossil taxa will supply further palaeoecological and palaeoceanographical data, which will be integrated with the geochemical data sets. All findings of my study will then be compared to planktonic and benthic foraminiferal data, to provide a truly multiproxy evaluation of the prevailing water-column conditions during this interval.