Ravines and gullies are erosional features that exist on a continuum of scales. A ravine is defined as a small, narrow, and deep depression, smaller than a valley, and larger than a gully (Bates and Jackson, 1984). Both grow by head cutting. Ravines are usually longer and deeper than gullies. Gullies may be small enough to plow, these are ephemeral gullies. Ravines are too large to traverse with vehicles. Gullies can often be identified by high Stream Power Index signature values (>7). Ravines can often be identified using a combination of terrain attributes, including slope, profile curvature and flow accumulation.
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