Structure and tectonic evolution of the Fuegian Andes (NW Scotia Arc) before and during development of the Scotia Sea

PABLO TORRES CARBONELL; LUIS V. DIMIERI; EDUARDO OLIVERO

Granada

Simposio; The Scotia Arc: Geodynamic Evolution & Global Implications; 2013

INSTITUTO ANDALUZ DE CIENCIAS DE LA TIERRA, ARMILLA (GRANADA).

Abstract: The orogenic history of the Fuegian Andes (Late Cretaceous-Miocene) is compared with the tectonic history of the Scotia Sea. Remarkable coincidences between both are found for the last 40-50 Ma, which are supported by recent structural studies in Tierra del Fuego that indicate contraction in the Fuegian Andes during activity of the Western Scotia Ridge, and onset of strike-slip faulting since the late Miocene. A Latest Cretaceous-Paleocene N-directed contraction recorded in the Fuegian Andes is more difficult to explain in the context of the South America-Antarctic Peninsula connection. We speculate that a complex bending of that connection triggered a northward movement of the Fuegian Andes backstop, which caused the recorded contraction.