![]() Also, as a river builds up its levees and raises itself over the floodplain, the slope and the transport power of the stream decrease, the channel fills gradually with sediment, and finally (often during a flood) the river will breach its levee (this process is called avulsion) and follow a steeper path down the valley. Meanders may cut into each other as they grow (neck cutoffs), and then the river shortcuts (growing meanders reduce the slope, cutoffs are a means to increase the slope again, feedback loop) and the old meander is abandoned and slowly fills with fine sediment during floods (oxbow lakes). Rivers that want to enter the main stream may not make it up the levee, and empty either into the backswamp (filing it up gradually) or flow parallel to the stream for a long distance until they finally join (yazoo streams). If the climate is humid the floodplain area beyond the levees may be covered with water most of the time, and may form a swamp (backswamp). Adjacent to the channel levee deposits build up. A meandering stream migrates laterally by sediment erosion on the outside of the meander. Description: Overview of features associated with meandering streams. Abandoned channels result from channel shifting processes at various scales, including meander cutoff and channel-belt avulsion. ^ Ritter, Michael E., The Physical Environment: an Introduction to Physical Geography, 2006, "Alluvial Landforms ".^ Gregorich, Soil and environmental science dictionary, CRC Press, 2001, ISBN 0-8493-3115-3, page 221.^ Stephen Codrington, Planet geography, Solid Star Press, 2005, ISBN 0-957, page 158.^ a b Ann Bowen, John Pallister, Understanding GCSE Geography, page 40, Heinemann, 2006, ISBN 1-0.Howell, Glossary of geology and related sciences: a cooperative project of the American Geological Institute, 1960, page 180 ^ Encyclopaedic Dictionary of Geography, M.S. A number of abandoned meanders occur along Elkhorn Creek and the Kentucky River, marking former routes of these streams.Jackson, American Geological Institute, Dictionary of geological terms, Random House, Inc., 1984, ISBN 1-9, page 315 ![]() Morris, Academic Press dictionary of science and technology, Gulf Professional Publishing, 1992, ISBN 0-12-200400-0, page 1333 In certain habitats, if the scar has sufficient water, or as an oxbow lake fills with sediment, these areas may become marshes or wetlands. The contestants made their wages and in a moment I will give you the final Jeopardy answer. oxbow lake, small lake located in an abandoned meander loop of a river channel. Due to higher velocity current on the outer banks of the river through the bend, more erosion occurs causing the characteristic steep outer slopes. Meander scars are caused by the varying velocities of current within the river channel. It is when an embedded meander is cut, forming a horseshoe-shaped lake what remains of the land is known by. This allows the curve to evolve over time another type of meander is considered. Both uses, however, describe features of the same process. It is a type of free meander very frequent to find in alluvial plains with few slopes or on sediments that have not been consolidated. The term itself may refer alternatively to the actual cuts into the bank of a bluff, or to the general feature of a drying or dried meander. They are characterized by "a crescentic cut in a bluff or valley wall, produced by.a meandering stream." They are often formed during the creation of oxbow lakes. 2010 astronaut photo from ISS.Ī meander scar, occasionally meander scarp, is a geological feature formed by the remnants of a meandering water channel. The abandoned meander is located in northern Saxony, Germany, close to the village of Löbnitz (Fig. Geography Incised or Entrenched Meanders In streams that flow rapidly over steep gradients, normally erosion is concentrated on the bottom of the stream channel. Geological feature Meander scars, oxbow lakes and abandoned meanders in the broad flood plain of the Rio Negro, Argentina.
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