Ravine
From FIS Freestyle wiki

1. Bluff: A near-vertical exposure of unconsolidated sediment (as opposed to a cliff, which is a near-vertical exposure of rock). 2.Ecotone: A transition between ecosystems. A ravine is an ecotone: a meeting of land and water, highland and lowland. 3. Gully: A newly formed, near-vertical-walled channel. 4. Headwater Erosion: The process of stream channel building that erodes the soil at the upper end of the ravine. 5. Moraine: The ridge of sand, clay and gravel sediment left at the leading edge of the glacier. 6. Ravine: An erosional feature cut into the side of a hill; V-shaped when young, U-shaped with age. 7. Seep: A small spring where groundwater exits between layers of rocks or sediment. 8. Slump: The falling away of large sections of a bluff or ravine’s sides — often caused as waterlogged slopes weaken after winter freeze-thaw cycles and spring rains. 9. Streambed Armor: Eroded stones and boulders left in the base of the ravine, ranging from a few inches to more than a foot across.
Ravine is a very small valley—almost like a canyon but narrower—which is often the product of streamcutting erosion. Ravines are typically classified as larger in scale than gullies, although smaller than valleys.
A ravine is generally a slope landform of relatively steep (cross-sectional) sides, on the order of twenty to seventy percent in gradient.
Ravines may or may not have active streams flowing along the downslope channel which originally formed them; moreover, often they are characterised by intermittent streams, since their geographic scale may not be sufficiently large to support a perennial watercourse.
[edit] Also see
[edit] Reference
Return to Mountain, Mountain Glossary, Snow and Weather Glossary, Working with Snow, Freestyle Skiing