A general theory for the effect of local topographic unevenness on contourite deposition around marine capes. An inverse problem applied to the Italian continental margin (Cape Suvero)

The interaction between ocean bottom currents and topographic obstacles often results in sedimentary processes that form intriguing sedimentary deposits. However, without a thorough knowledge of both fluid mechanical processes and oceanographic settings regarding these sedimentary deposits, such an inherited interaction is not easy to understand. We here analyze the interaction between a bottom, geostrophic current and a local topographic depression, a slide scar offshore Cape Suvero, an Italian headland in the southern Tyrrhenian Sea, in order to explain the presence of contourite drifts off this cape. We apply the classical conservation of marine water potential vorticity and demonstrate the presence of a steady cyclonic circulation over the scar, which in turn affects contourite deposition. We thus show that the application of the potential vorticity conservation provides a simple but powerful, general tool for the understanding of the complex relations among ocean current, seafloor morphologies and sedimentary structures. (C) 2016 Elsevier B.V. All rights reserved.