Before revision: The former is the result of water action, as is the case for other types of scours (bridge and tidal scours); the latter are produced by drifting ice and are most often linear features.
After revision: , also called gouges,The former is the result of water action, as is the case for other types of scours (bridge and tidal scours); the latter are produced by drifting ice and are most often linear features.