MORPHOSEDIMENTARY ANALYSIS OF THE SLOGGETT SUBMARINE CANYON AND ITS REGIONAL IMPLICATIONS. NW SCOTIA SEA

FERMIN IGNACIO PALMA; FEDERICO DAMIÁN ESTEBAN; JOSÉ ISOLA; SEBASTIÁN PRINCIPI; JUAN PABLO ORMAZABAL; GRAZIELLA BOZZANO; DANIELA SPOLTORE; MARÍA EMILIA BRAVO; CÉSAR ARTUNDUAGA; ALEJANDRO TASSONE

Atenas

Conferencia; Regional Conference on Geomorphology; 2019

International Association of Geomorphologists

The south Argentine Continental Margin (ACM) is incised by deep and large canyons thatbelong to the canyon’s system of Tierra del Fuego. The Sloggett Canyon, located innorthwestern Scotia Sea, is the longest with a total length of 142 km along the thalweg,cutting the continental platform, slope and abyssal plain. In this work we present amorphosedimentary and structural analysis of the canyon revealed from recently dataobtained on board the R/V Austral in the YTEC-GTGM0 cruise in September 2017. It consistsin the first complete very-high resolution imaging (up to 20 meters) of the canyon from itsupper part down to its distalmost reach. Swath bathymetry with the echosounder EM-122 andsub-bottom profiler with Parasound P70 were used for distinguish morphologies made byprocesses of erosion, transport and deposition. The head is affected by tributaries channelsthat range in size, direction and depth and act as a conduit for gravity flows and turbiditycurrents. They have a wide expression in the east flank regarding the western flank wherepredominate wall slumping, gullies and scar. The canyon was studied considering three partsof the thalweg, where the direction changes abruptly two times from NW-SE to SW-NE in anangle of approximately 90 degrees. This was associated with the NW-SE lineaments of theWest Scotia Ridge, where could be acted as a path for the canyon and the Beagle ChannelFault System that has a W-E direction affecting the slope. Additionally, along- processesrelated to the strong oceanic currents form contourites drifts and erode the margin to formcontourites terraces along canyon depth. The canyon has a connection with the Sloggett Bay(10 km north) and can be considered as a continuation of the Sloggett Continental TectonicLineament.