Current controlled sedimentation in the Subantarctic region: calibration of paleocurrent reconstructions based on modern circulation

• Applicant: Dr. Gastón Kreps, Ph.D.
• Subject Area: Geology ; Oceanography
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 573262214

Ocean currents are known to play an important role in sedimentation in deep-water environments and are responsible for the formation of current-related deposits (i.e., contourites), which are exceptional high-resolution archives for palaeoceanographic and paleoclimatic studies. Despite the widespread use of such sediments in paleo-reconstructions, there is still no universal calibration of paleocurrent proxies based on grain-size data. In order to interpret the oceanographic processes at the origin of deep-marine sediments, it is crucial to conduct studies that combine analyses of bottom current dynamics with seafloor geological observations. The CUCO project proposes investigating the dynamics of the bottom currents in the sub-Antarctic region, an area of intense near-seafloor circulation and abundant contourites. The Southern Ocean is the central element of the global overturning circulation connecting water masses from the Atlantic, Indian and Pacific Oceans. It is strongly influenced by the Antarctic Circumpolar Current (ACC), which is constrained by topography and presents large eddies that reach the seafloor and can affect bottom currents and sedimentation locally and in the adjacent basins. The present study proposes to utilise ocean reanalysis to investigate the dynamics of the bottom over the last 30 years in the sub-Antarctic region, with a view to ascertaining the role of eddy variability in the ACC on the meridional transport in the adjacent basins. This approach is expected to yield significant new insights into the processes controlling the global overturning circulation. The objective of this study is to make a comparison between the intensity and variability of bottom currents and the geochemical and sedimentological properties of surface sediments. This will allow proxies for paleocurrent reconstructions to be calibrated, and thus improve palaeoceanographic reconstructions based on the sedimentary record.

• DFG Programme: Research Grants
• International Connection: Argentina, USA
• Cooperation Partners: Professorin Dr. Silvia Romero; Wilbert Weijer, Ph.D.
• Co-Investigators: Dr. Frank Lamy; Professorin Dr. Elda Miramontes García