- Crevasse splay
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A crevasse splay is a sedimentary fluvial deposit which forms when a stream breaks its natural or artificial levees and deposits sediment on a floodplain. This breach can cause large deposits that spread in a pattern similar to that of an alluvial fan deposit. Once the levee has been breached the water flows out of its channel. The larger sediments are deposited first and as the water loses energy the smaller grains fall out of suspension. This can create graded deposits similar to those found Bouma sequences. In some cases crevasse splays can cause a river to abandon its old river channel, a process known as Avulsion. [1] Crevasse splay deposits occur most commonly on the outside banks of meanders where the water has the highest energy. The deposits can range in size. Larger splays can be 6 meters thick at the levee and spread 2 kilometers wide. While smaller splays may only be centimeters thick. [2]
See also
References
- ^ Boggs, S. Jr., 2012, Principles of Sedimentation and Stratigraphy: New Jersey, Prentice Hall, 218 p.
- ^ Mjøs, R., Walderhaug, O. and Prestholm, E. (2009) Crevasse Splay Sandstone Geometries in the Middle Jurassic Ravenscar Group of Yorkshire, UK, in Alluvial Sedimentation (eds M. Marzo and C. Puigdefábregas), Blackwell Publishing Ltd., Oxford, UK.
External links
Categories:- Rivers
- Fluvial landforms
- Geography terminology stubs
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