Structure and sedimentary architecture of the southwestern margin of the Scotia Sea.

ROVIRA, I.; TASSONE A.; LODOLO E.

Buenos Aires

Workshop; Giambiaggi School- Applied and Enviromental Geophysics; 2012

FCEyN. Dpto. Física.

Through the compilation of available geophysical data (bathymetric, gravity, magnetic and seismic) it was possible to identify and map the structure and stratigraphy of the southwestern corner of the Scotia Sea. Integration of compiled information indicates that, structurally, the studied area is composed by continental, stretched continental and oceanic crust, which once were part of the continental link between Antarctica and South America. During the latest Cenozoic these blocks were fractured and displaced by extensive, compressive and strike slip tectonic phenomena. This led to the formation of sedimentary basins linked to the opening of the Drake Passage and the development of current Scotia Sea. Sedimentary architecture analysis resulted in the definition of five sedimentary units (bottom to top: I, II, III, IV, V) separated by four main seismic discontinuities (bottom to top: d, c, b, a) each one of them associated to a major tectonic event. These sedimentary units were interpreted as deposits related to contour currents (contourite drifts). The study of these currents and its deposits are the key to understanding the geographic and climatic, ancient and current, development both for the studied region and the whole world.