Silvia Romero (Servicio de Hidrografía Naval , Argentina); Graziella Bozzano (Servicio de Hidrografía Naval , Argentina); Ornella Silvestri (Servicio de Hidrografía Naval , Argentina)

This is a project that aims to generate new knowledge on the interaction between submarine morphology associated with submarine canyons on the Argentine Continental Margin (ACM) and the oceanographic dynamics linked to the Malvinas Current (MC), in two key sectors of the shelf break: the Patagonian region (from now on Southern System, 44-45°S) and the Bonaerense region (from now on Northern System, 40-41°S). Research activities are scheduled between September 22 and October 22, 2025, on board the oceanographic vessel Falkor (too). The scientific team is composed entirely of Argentine researchers, led by members of the Servicio de Hidrografía Naval (SHN) and the Centro de Investigación del Mar y la Atmósfera (CIMA-UBA-CONICET). The remaining participants form a multidisciplinary group with extensive experience in oceanography, marine geology, and biology. The central hypothesis is that the submarine valleys associated with the canyons, especially where their head incises the continental shelf, alter the circulation of water masses, promoting the intrusion of slope waters from the MC—cold, saline, and nutrient-rich—onto the continental shelf. This input of deep waters would enhance the fertilization of shelf waters—warmer and less saline—thus supporting high biological productivity and sustaining abundant fishery resources along the shelf-break of the Argentine Sea. The precise location of the canyon heads will be determined using high-resolution geomorphological data acquired with a multibeam echo sounder and a sub-bottom profiler. For the first time, these environments will be explored through dives conducted by the ROV, allowing direct visual characterization of habitats. Hydrographic and biological measurements will be carried out around the canyon heads through water sampling and plankton net tows, with the goal of understanding the coupled physical-biological dynamics in these areas. Additionally, in the Northern System, in the framework of PATASWOT project and a PhD thesis, current meters will be deployed on two landers and a moored surface buoy (Wavescan type) with meteorological and subsurface instruments to generate time series of current velocity, temperature and salinity, and GPS-tracked surface drifters, to study the trajectories and hydrographic characteristics of the currents as they cross the area to verify the surface circulation patterns generated by the interaction with the submarine canyon. This project represents a significant step forward in understanding oceanographic processes and their coupling with seafloor morphology and biological systems, through an interdisciplinary approach that has not yet been developed at this level of detail in Argentine waters. It will constitute the first comprehensive, high-resolution study of submarine canyons on the Argentine continental margin, in a region of high ecological and economic value due to the presence of key fishery resources. The fortunate combination of advanced technologies and integrated methodologies presents a unique opportunity to carry out this study. The expected outcome is the generation of critical knowledge on the dynamics of nutrient availability on the Argentine shelf, its implications for the trophic web, and its influence on commercially important species.