ICECARB

Summary:

The superordinate project objective is to verify the hypothesis that tropical carbonate platforms since the onset of the middle and late Miocene global cooling are strongly controlled by ocean currents. It is proposed that the modern carbonate platforms are in an "icehouse world mode". Four aims will allow achieving this goal: By linking seismic reflection- with stratigraphic data from Ocean Drilling Program Leg 133 sites at the Queensland Plateau carbonate platform, the backstepping of carbonate bank margins will be understood. Here, the focus is on the mapping and correlation of current features such as submarine dunes, drift bodies or current moats. Recent and youngest depositional processes of the carbonate banks will be analyzed with multibeam and Parasound determining ocean current impact on the carbonate source to sink system (e.g. sediment thickness distribution, slope instabilities). Sedimentary variations with regard to carbonate bank exposure to currents and wind will be analyzed via sediment composition (grain size, texture, components), linking geological and geophysical data. To assess how the carbonate banks exposed to ocean currents disturb the water mass stratification, CTD stations will be measured up- and downcurrent of the buildups.