Assertion: canyon | /r/MadeOf | erosion
Facets:
value: by running water
type: CAUSE
Source sentences:
text: Canyons can be formed by erosion by running water which will take rocks and soil away.
text: The Fish River canyon consists of an upper canyon, where river erosion was inhibited by hard gneiss bedrocks, and a lower canyon formed after erosion had finally worn through the gneisses.
text: A canyon has to be formed through erosion.