Establishing a new and detailed mid-Cretaceous palaeoceanographic record for the SE Pacific domain from Peru - Phase 2

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Our understanding of the mid-Cretaceous (Aptian to Turonian) paleoceanography of the east Pacific realm is severely hampered by the poor recovery of pelagic sequences from OPD and IODP core material and a limited number of land-based studies. At present, only a very limited number of studies from for example Mexico and Columbia exist. Therefore, well-constrained data on the impact of mid-Cretaceous anoxic events (OAE) in the SE Pacific are extremely rare, a feature that highlights the disproportional regional bias of Atlantic and Tethyan case studies. As a result of a DAAD scholarship obtained by the Peruvian PhD student Mr. Juan Pablo Navarro Ramirez for 3.5 years, and thanks to the generous support of the DFG (proposal BO 3655/2), we have been able to perform a first phase of fieldwork and compile a synthetic chemostratigraphic sections spanning the latest Aptian - Turonian interval in the Cajamarca region. We have clearly documented that fieldwork in Peru is achievable and that bulk micrite carbon isotope sections bear the characteristics of well-studied intervals in Europe and elsewhere. Here, we apply for a renewed support of the DFG (phase 2 of this project), scheduled to last 27 months. We would like to perform a second fieldwork phase that aims at assessing the spatial differences in the carbon isotope signature, and hence local carbon signals, of the vast epeiric neritic shelf of South America in Peru. It also aims at understanding the role of regional vs. global nutrient level changes in the production and preservation of organic matter in Peru.