Slope morphology adjacent to the cool‐water carbonate shelf of South Australia: GLORIA and Seabeam imaging

Abstract

A combined GLORIA, Seabeam and high‐resolution seismic survey was conducted over a selected area of the southern Australian continental margin. The survey focused on the continental slope immediately seaward of the wide cool‐water carbonate shelf, in a region dissected by a suite of large submarine canyons. Examination of the data underscores the significance of mass‐wasting processes in the development of slope morphology. Slump scars and obvious sediment slides are virtually ubiquitous, in many cases being sourced immediately below the shelf break and connecting downslope with erosional channels. The channels themselves possess what appear to be degraded levee banks suggesting possible spill‐over of turbidity currents which themselves may have been triggered by the upper slope slides. The age of these large‐scale sediment movements remains uncertain, however, and it is currently unclear whether or not they relate to specific sea‐levels. A pair of east‐trending scarp‐like features dominates the mid‐slope...