The Campanian - Maastrichtian (Late Cretaceous) climate transition: the history of palaeoceanographic changes

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The latest Cretaceous was characterised by the transition of the Earth´s system from the Cretaceous greenhouse to the cooler Cenozoic climate that includes several perturbations in the global carbon cycle. The aim of this project is to investigate the history of changes in ocean circulation and deepwater formation in the tropical Pacific (Site 1210B, Shatsky Rise) relative to the latest Campanian to early Maastrichtian carbon isotope events (CMBE and MME). The history of changes in surface- and deep-water temperature will be reconstructed in the course of the carbon isotope events using highresolution benthic and planktic foraminiferal stable isotope analyses. Changes in ocean circulation and the source regions of different deep and intermediate water masses will be deciphered by using radiogenic isotopes (Nd). Nd isotope analyses of ferromanganese oxide coatings of bulk sediments from the tropical Pacific, the South Atlantic and the Southern Ocean will allow the reconstruction of deep-water isotope signatures. By comparison of different locations past water mass flow in the tropical Pacific and its relationship to carbon cycle perturbations will be reconstructed. Thereby, the developed age-model comparison between various ocean and shelf-sea sections provides the unique opportunity to recognize leads and lags between the carbon cycle and ocean circulation.