Platform evolution around the Early Eocene Climatic Optimum (EECO) in a low latitude setting

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During the Eocene a large number of biotic and oceanic perturbations are recorded that, however, are underexplored with respect to their repercussions on carbonate platforms. The proposed project will contribute to understand the interaction between carbonate production, major changes in carbon cycles and global/local climate changes. We will study the sediment dynamics, the faunal/floral composition, habitats, and changes of carbonate-segregating organisms, to filter out the effects of warming and cooling on the environment and the biota. We will focus on global warming events, like the EECO (Early Eocene Climate Optimum), a long-term warming episode during Early-Middle Eocene or short-term warming events (hyperthermals) like the Elmo or the “x-event” in the Early Eocene. Comparisons with data from warming events and biotic changes on carbonate platforms, e.g. during the PETM (Paleocene/Eocene Thermal Maximum - a short-term warming episode at the Paleocene/Eocene boundary) will allow to define the important paleontologic and sedimentologic parameters of carbonate platforms that are due to climatic perturbations, closely linked to the global carbon cycle. We will concentrate on the various Eocene platform environments and platform-slope settings of the NGWA (North Galala-Wadi Araba High, Egypt) that are linked with basinal settings and thus allow the correlation of platform events with oceanic events. Carbonate platforms, such as the NGWA, reflect the typical end-members of a tropical carbonate factory, a term that describes both the places and processes of carbonate precipitation. In comparison to pelagic systems, the contribution of carbonate platforms within coupled climatic and oceanographic processes is rather unknown; the same applies to the Paleogene platforms. Moreover, the role of the carbonate producers, in particular, is only known rudimentarily. We will use different methods and proxies, including the following approaches: Quantitative facies analysis in the field and in laboratory analyses, stratigraphic modelling, paleontolo-gic analyses on: corals, larger foraminifera, calcareous algae; determination of geochemical variations (δ13C) and calculations of calcification rates of carbonate-segregating organisms to interprete oceano-graphic and climate-sensitive signals. Integrating traditional field geology methods (1D sections and several 2D large-scale maps) with quantitative geological mapping will help to better understand facies proportions and distributions in both horizontal and vertical orientation and to reconstruct the structural and stratigraphic architecture of the platform within an integrated 3D georeferenced framework, including the application of 2D (PHIL) and 3D (DIONISOS) stratigraphic forward modelling. The integration of all data will allow the interprettation of small-scale sedimentary processes on platforms during the EECO to better understand the impact of climatic forcing on carbonate factories.