Morpho-sedimentary features of the south-western Scotia Sea

ROVIRA, I.; TASSONE, A.; ESTEBAN, F.

BOLLETTINO DI GEOFISICA TEORICA ED APPLICATA

ISTITUTO NAZIONALE DI OCEANOGRAFIA E DI GEOFISICA

Lugar: Trieste; Año: 2013 vol. 54 p. 343 - 345

0006-6729

The opening of the Drake Passage, occurred most likely, at the Late Oligocene-Early Miocene boundary, has triggered a series of palaeogeographic and palaeoclimatic events on a global scale (Barker, 2001). These are associated to the profound modifications of the oceanic water masses circulation responsible of the formation of the Antarctic Circumpolar Current, and its interaction with the Weddell Gyre (Figure 1A) (Lodolo & Tassone, 2010). These bottom currents have been responsible for the distribution, shape and size of widespread contouritic drift deposits (Maldonado et al., 2006). The studied area includes the sector located to the north of the South Scotia Ridge, and comprises the two continental/transitional blocks of the Terror Rise (TR) and the Ona Platform (OP). These blocks probably resulted from left-lateral transcurrent motion which took place along the South Scotia Ridge (SSR) since the early development of the western part of the Scotia Sea (Lodolo et al., 2006; Civile et al., 2012). Since the Late Miocene onwards, this area remained mostly tectonically silent, but the sedimentary processes might have been affected by the transpressional uplift of the Shackelton Fracture Zone (SFZ) and the separation of the South Shetland Islands Block (SSIB) due to the incipient subduction of the SFZ (Barker, 2001; Maldonado et al., 2006; Civile et al., 2012).