Response of terrestrial environments to short-term climate perturbations: Low-latitude signals during the mid-Cretaceous super greenhouse world (ODP Leg 207, Demerara Rise)

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The project aims at deciphering terrestrial environmental dynamics during the mid-Cretaceous supergreenhouse world based on the analysis of pollen and spores in marine sediments. This approach allows a straightforward correlation of data from the terrestrial and marine realms, thus yielding the opportunity to obtain a comprehensive view of global change. High-resolution palynological analyses will be carried out across the Cenomanian/Turonian boundary interval (CTBI) to assess terrestrial environmental change during formation of the Oceanic Anoxic Event 2 (OAE 2) black shale representing a major perturbation of the global carbon cycle. To assess terrestrial environmental change in the tropics, palynological analyses will be carried out on two CTBI sections from OOP Leg 207 (Demerara Rise). Complementary analyses will be performed on mid-latitude CTBI records from DSDP Site 551 (off SW England) or Wunstorf (N Germany) to obtain a regionally differentiated picture of terrestrial environmental change. The project has been designed to achieve the following main goals: (1) Identification of terrestrial climatic perturbations (such as precipitation and temperature change) connected to OAE 2 formation in the tropics and mid-latitudes. (2) Testing the hypothesis of a significant pC02 drop connected to OAE 2 formation. (3) Providing an estimate of terrestrial input into the marine realm at Demerara Rise during OAE 2 formation. (4) Identification of leads and lags between environmental signals from the terrestrial and marine realms during OAE 2 formation.