Resumen de A contourite system offshore the Rio de la Plata estuary, Argentina
Tammo Huppertz, Till Hanebuth, Rüdiger Henrich, Benedict Preu, Tilmann Schwenk, Michael Strasser
The Argentine continental margin is influenced by the highly dynamic oceanic regime formed by the tropical-polar front displayed in the Brazil-Malvinas-confluence zone, where Antarctic and tropical water masses collide. Contourite deposits described from below the confluence zone on the Ewing terrace at ~1200 m water depth are characterized using lithology, x-ray data, MSCL data and parasound data. Grain size and petrology will further characterize the deposits. On the basis of these characteristics, 9 different facies were defined. They display either purely contouritic deposition, or show post depositional reworking and possible initial creep. This observation suggests that the contourites may be unstable as a result of downslope processes which were initiated by high excess pore pressures may have destabilized large parts of the outer terrace.
