SEDIMENTARY MODEL OF A MIXED DEPOSITIONAL SYSTEM: THE PACIFIC MARGIN OF THE ANTARCTIC PENINSULA

Downslope turbidity currents and alongslope bottom currents are common processes along continental margins. When the two processes act during successive times, interaction can be recorded by variations of sediment body morphology, alternations of turbidite and contourite deposits or by the presence of bottom current reworked turbidites. However, the ability to discriminate contourites from turbidites has proven to be difficult in mixed systems, where multiple processes interact with each other. One such system is identified on the offshore Pacific Margin of the Antarctic Peninsula, where contourite drifts and turbidity channel systems occur on the continental slope and rise. This work aims to better understand how bottom currents and turbidity currents controlled the development of a mixed depositional system in the Pacific Margin of the Antarctic Peninsula. Furthermore, knowledge in this margin is still scarce, concerning: i) the role and interaction between alongslope bottom currents and downslope turbidity currents; ii) the relationship with the main regional events; and iii) how to discriminate the mechanisms responsible for the formation of contourite features and the factors controlling the formation of turbidite features and how they operated through time. To approach these objectives, we employed high-resolution datasets: high-resolution seismic data, swath multibeam bathymetry, sediment samples and X-Ray Fluorescence data of the SEDANO Cores 11, 12, 13, 18 and 20. Its interpretation and integration aims to propose the construction of a sedimentary model for a modern mixed depositional system, which will clarify the role and influence of bottom currents versus turbidity currents. This modern mixed system could be a good analogue for a better understanding of similar mixed depositional systems in the ancient record.