El límite Cuenca Powell/Mar de Weddell. Estructura y relación con la fragmentación Cenozoica de la Península Antàrtica

Abstract

Late Paleogene to Neogene continental fragmentation of the Northern Antarctic Peninsula caused the development of small oceanic-floored basins such as Powell Basin. On the basis of MCS profiles and swath bathymetry collected during Hesant 92/93 cruise, a tectonic map of the transition zone between Powell Basin and the Weddell Sea, a Mesozoic oceanic domain opened during the Condwana breakup, was ellaborated. The E-W morphologic high (50x250 km) that separates these two domains has features of an interbasin antithetic ridge developed in a transtensional regime. This tectonic high appears to be a fragment of the western passive margin of the Weddell Sea, strongly modified during the late Cenozoic by the Powell Basin development tectonics