The modern carbonate contourite drift of the Little Bahama Bank: a geophysical, sedimentological and biostratigraphic study

We focus on a major sedimentary body situated of the northwestern slope of the Little Bahama Bank (LBB), the second largest carbonate bank of the Bahamian archipelago. Our objectives are (1) to determine sediment export processes from the shallow-water bank to the northern slope of LBB, which is exposed to prevailing winds (windward side) and (2) to evaluate sediment deposition related to variations in the regional Antilles Current. This work focused on two marine cores located on the western side of the northern slope of LBB in combination with high-resolution bathymetric and very-high resolution seismic data (Chirp) collected during the CARAMBAR cruise (2010). Off-bank processes are the major sedimentary processes during sea-level highstands, resulting in high accumulation rates of foraminifera- rich carbonate ooze deposits. Interglacial clay-rich deposits may be related to a slowdown of currents, allowing clay-size particles to settle within the contourite system, and an increase of clay production and export from continental areas. Glacial deposits are less massive and show a bioturbated coarsening-up unit succeeded by a bioturbated fining-up unit. The presence of coral mound and non-deposition areas and/or erosion is an additional evidence of bottom current circulation shaping the northward-elongated hemi-conical contourite body