A contourite system offshore the Rio de la Plata estuary, Argentina

• Tammo Huppertz ^[1] ; Till Hanebuth ^[1] ; Rüdiger Henrich ^[1] ; Benedict Preu ^[1] ; Tilmann Schwenk ^[1] ; Michael Strasser ^[1]
  1. [1] University of Bremen

     University of Bremen

     Kreisfreie Stadt Bremen, Alemania

     
• Localización: Geotemas (Madrid), ISSN 1576-5172, Nº. 11, 2010 (Ejemplar dedicado a: Deep-Water Circulation: Processes & Products. International Congress. Baitona, Pontevedra, Spain. 16 & 17 June 2010), págs. 77-78
• Idioma: inglés
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• Resumen

  • 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.