Contourite and mixed turbidite-contourite systems in the Mozambique Channel (SW Indian Ocean): Link between geometry, sediment characteristics and modelled bottom currents

Oceanic currents can profoundly reshape the seafloor and even modify characteristics of turbidite systems. Multiple erosional depositional features directly formed by bottom (i.e. contourites), as well interaction between turbidity or systems mixed turbidite-contourite systems) have been identified in Mozambique Channel (SW Indian Ocean) multibeam bathymetry, seismic reflection data, sub-bottom profiler images sediment cores. In this study, we characterise morphology, stacking pattern sedimentary these systems, analysed properties at using a hydrodynamic numerical model. Modelled are highest abraded surfaces moats, but they also display relatively high variability, suggesting that observed erosion is not result constant persistent current rather episodes intense circulation. contourite terraces significantly different from related plastered drifts, where accumulation enhanced. The formation thus solely be explained mean oceanic circulation eddies, implying other processes such internal waves may play relevant role their formation. Three types were observed: one characterised asymmetric channel-levee synchronous currents, phased resulted channel flanks another which both played evolution system. Finally, propose simplified classification contourites applied to any system worldwide, comprises features, including muddy sandy deposits.