Influence of sea-level rise on carbonate ramp sediment dynamics: Micro-XRF- and XRM-supported investigation of high-energy deposits (Upper Muschelkalk, North Germany)

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The research project aims to investigate the sediment dynamics of Upper Muschelkalk ramp carbonates (Trochitenkalk, m7, Triassic) in South Lower Saxony that were deposited during a major third-order sea-level rise. Main focus of this project is the region Hildesheimer Wald, south of the city of Hildesheim. It is characterized by a paleo-high, called “Hildesheimer Schwelle” and related high-energy deposits (Trochitenkalk, m7, Triassic). Previous studies were mainly focused on facies classification. However, relatively little or no attention has yet been paid to the lateral facies distribution and continuity, lateral facies transitions, diagenesis and the paleohydrodynamic regime, whose reconstruction is an important step to understand the sediment dynamics. Besides standard sedimentological techniques to study outcrops (e.g. log measurement, sampling, spectral gamma-ray) and thin sections (polarized light microscopy, cathodoluminescence microscopy), new tools such as an 3D X-Ray Microscope (XRM) and a micro X-Ray Fluorescence Spectrometry scanner (XRF) will be used to investigate rock samples of the Upper Muschelkalk successions in the region Hildesheimer Wald related to the following subjects: -Changes in the sedimentary and hydrodynamic system during rising sea-level.-Diagenesis analysis: Interplay of sedimentary structures and diagenetic processes. The results of the project will improve the fundamental understanding of the complex and changing conditions of the sedimentary system on carbonate ramps during a rising sea-level, which may help to comprehend and to predict similar changes and processes in modern systems. In addition, the results will improve the principal understanding of diagenesis processes and interplaying sedimentary structures.