A REVIEW ON GEOMORPHIC RESPONSE OF SUBMARINE CANYONS TO TECTONIC DEFORMATION

The submarine canyon is one of the most important morphological features on the continental margin, which acts as major conduits for transporting organic matters and sediments from the continent and continental shelves into the deep sea. They are significant for the researches of deep-water gravity flows, global carbon circulation, deep-sea biodiversity, petroleum and gas hydrate exploration and submarine engineering etc. Submarine canyons commonly occur on continental margins influenced by tectonic deformation. This paper presents a brief review on the geomorphic responses of submarine canyons to tectonic deformation. Five end members in terms of planar distribution of submarine canyons related to tectonic deformation are summarized, i.e. tectonically confined, diverted, deflected, blocked, and cutting-across submarine canyons, respectively. The interaction between submarine canyons and variations in longitudinal gradient induced by structural deformation is also analyzed. Increase in slope gradient may cause enhanced erosion of the gravity flows and the development of knickpoints within the canyons, whereas levees and frontal splays tend to occur as slope gradient decreases. Channel sinuosity is the dynamic response to the changes in slope gradient.