Contourites and Slope Progradation: Canterbury Basin, New Zealand

• Craig Fulthorpe ^[1] ; Hongbo Lu ^[2] ; IODP Expedition Shipboard Scientific Party
  1. [1] niversity of Texas Institute for Geophysics
  2. [2] Shell International Exploration and Production
• 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. 45-46
• Idioma: inglés
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• Resumen

  • The offshore Canterbury Basin exemplifies sequence development on a prograding passive margin influenced by submarine currents. Middle Miocene to recent regional sequence-bounding unconformities probably record global sea-level (eustatic) cycles, but sequence architecture is strongly influenced by local processes and basin stratigraphy records the development of ocean circulation in the region. Along-strike currents created large, elongate sediment drifts with adjacent (landward) moats. Drifts aggraded to upper slope depths, focusing deposition on the slope and reducing the rate of basinward advance of the shelf edge, thereby reducing slope inclination. Slope drifts were so pervasive in parts of the basin that progradation occurred by the accretion of successive drifts. Coeval clinoform geometries along strike from active drifts suggest that currents might influence clinoform formation even in locations lacking seismic evidence of mounded drifts. Elongate drift development terminated during themid-Pliocene, perhaps because increasing eustatic amplitudes and long-term eustatic fall enhanced downslope sediment transport processes.