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Seismic stratigraphy of Lago Fagnano sediments (Tierra del Fuego, Argentina)- A potential archive of paleoclimatic change and tectonic activity since the Late Glacial Located at 54º S in the heart of the Island of Tierra del Fuego, Lago Fagnano occupies the deepest of a chain of en-echelon tectonic depressions along the Magallanes-Fagnano Transform system (MFT). A recent geophysical campaign combining 3.5 kHz (pinger) single-channel with 1 in3 airgun multi-channel systems surveyed more than 100 m of glacio-lacustrine sediments filling two main sub-basins. These data provide a unique opportunity to visualize the most recent lacustrine sequence with high-resolution while simultaneously imaging the oldest infill. A preliminary seismic stratigraphic analysis of the high-resolution 3.5 kHz pinger data allowed the identi-fication of three major seismostratigraphic units (A, the oldest and C, the youngest). While unit A is interpreted as glacially derived sediments, the overlying unit B is interpreted as fining upward sequences of proglacial tur-bidites reflecting sediment pulses released by the retreating Fagnano glacier during the last deglaciation. A major environmental change occurred during deposition of unit C when pelagic style of sedimentation is inter-calated by sequences of downslope mass flow events probably triggered by relatively strong tectonic pulses along the MFT system. Gravity cores show a regular alternation of light and dark laminae occasionally inter