High-resolution sequence stratigraphy of stacked fan delta sequences, Corinth Rift, Greece

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The effects of tectonism, sediment supply and eustacy on accommodation changes are often difficult to untangle. In this aspect fan deltas are valuable because they are sensitive recorders of depositional variability around the continental-marine (or lacustrine) transition. Here we propose a pilot study that is aimed at the recognition, correlation and high-resolution dating of depositional sequences from basin margin (shelf) to basin centre. For this purpose the Plio-Pleistocene fan delta successions in the Gulf of Corinth are highly appropriate since they are relatively small, well accessible and enable good visual correlations of the entire delta-to-prodelta transect. Drowning or submergence phases of conglomeratic delta topset beds will be detected through cathodolumiscence analyses of the cement composition and –stratigraphy. The expression of depositional sequences in the pro-delta facies will be studied by means of gamma-ray spectrometry, XRD analysis of the clay fraction and palynofacies. The results of these methods can be used as proxies for Milankovitch cyclicity, climatic variability, or the continental influence. It is supposed that the nature of the topset- and prodelta sequences and their correlation will give important information on controls on sediment supply and accommodation changes. Our results will be incorporated into a conceptual sequence stratigraphic framework.