Ravine

[1] Ravines may also be called a cleuch, dell, ghout (Nevis), gill or ghyll, glen, gorge, kloof (South Africa), and chine (Isle of Wight) A ravine is generally a fluvial slope landform of relatively steep (cross-sectional) sides, on the order of twenty to seventy percent in gradient.

[2] According to Merriam-Webster, a ravine is "a small, narrow, steep-sided valley that is larger than a gully and smaller than a canyon and that is usually worn by running water".

[3] Gullies are often found in hilly or mountainous regions, where water runoff is guided downhill by steep slopes and over time erodes the landscape.

[3] A gully can be classified as a ravine after it reaches a large depth, typically in excess of 5 metres (16 ft).

[6] In Indian badlands, soil erosion is estimated to exceed a rate of 40 tonnes per hectare (16 long ton/acre; 18 short ton/acre) annually.