Classification of submarine canyons of the Australian continental margin

摘要

Submarine canyons influence oceanographic processes, sediment transport, productivity and benthic from the continental shelf to the slope and beyond. However, not all canyons perform the same function. relative influence of an individual canyon on these processes will, in part, be determined by its form, shape position on the continental margin. Here we present an analysis of canyon geomorphic metrics using an national dataset of 713 submarine canyons surrounding mainland Australia. These metrics (attributes) for canyon are used to classify them into canyon types across a hierarchy of physical characteristics separately shelf-incising (n = 95) and slope-confined (blind; n = 618) canyons. We find that the canyon metrics a wide variety of canyon form and complexity that is consistent with a population of canyons that has at different rates around the Australian margin since the break-up of Gondwana. The large number of confined canyons is interpreted to reflect dominance of slope mass-wasting processes over erosive flows from fluvial and shelf sources on an arid continent. The distribution of submarine canyons around Australian margin is not regular, with clusters occurring in the east, southeast, west and southwest where margin is steepest. The classification result provides a quantitative framework for describing canyon for application in studies of geological controls on individual canyons, canyon oceanography and biodiversity. (C) Crown Copyright 2014 Published by Elsevier B.V.