canyon submarine canyon A steep-sided valley on the sea floor of the continental slope. Many submarine canyons are found as extensions to large rivers; however there are many that have no such association. Canyons cutting the continental slopes have been found at depths greater than 2 km below sea level. Many submarine canyons continue as submarine channels across continental rise areas and may extend for hundreds of kilometers. ENVO ENVO:00000267 EcoLexicon:submarine_canyon FTT:421 Geonames:U.CNSU Geonames:U.CNYU SubmarineCanyon TGN:23415 TGN:23416 Wikipedia:Submarine_canyon canyon canyons undersea canyon undersea ravine