Debouch

{{short description|Water runoff from a smaller place to a larger one}} {{use mdy dates|date=March 2023}} [[File:Iss016e019375.jpg|thumb|The port and city are the southern terminus of the Suez Canal, which flows through Egypt and debouches into the Gulf of Suez near Port Tawfiq]]

In hydrology, a '''debouch''' (or '''debouche''') is a place where runoff from a small, confined space discharges into a larger, broader body of water. The word is derived from the French verb {{lang|fr|déboucher}} ({{IPA|fr|debuʃe|pron}}), which means {{gloss|to unblock, to clear}}. The term also has a military usage.<ref>{{Cite book |last=Ma |first=Yanxia |url=https://scholarworks.wm.edu/etd/1539616757/ |title=Continental Shelf Sediment Transport and Depositional Processes on an Energetic, Active Margin: the Waiapu River Shelf, New Zealand |work=Dissertations, Theses, and Masters Projects |date=2009 |pages=2, 19 |doi=10.25773/v5-8w3d-wz58}}</ref>

==Geology== In fluvial geomorphology, a debouch is a place where runoff from a small, confined space emerges into a larger, broader space. Common examples are when a stream runs into a river or when a river runs into an ocean. Debouching can generate massive amounts of sediment transport. When a narrow stream travels down a mountain pass into a basin, an alluvial fan will form from the mass deposit of the sediment. The four largest rivers (the Amazon, the Ganges, the Yangtze and the Yellow) are responsible for 20% of the global discharge of sediment in to the oceans by debouches.<ref>{{Cite web |title=debouch as a noun |url=http://www.oed.com/view/Entry/47918?rskey=Lfbkiz&result=1&isAdvanced=false#eid |access-date=2012-10-10 |website=Oxford English Dictionary}}</ref>

==Geography== In fluvial geography, a debouch is a place where a body of water pours forth from a narrow opening. Some examples are: where a river or stream emerges from a narrow constraining landform, such as a defile, into open country or a wider space; a creek joins a river; or a stream flows into a lake.<ref>{{Cite magazine |last=Mitchell |first=Martha S. |date=May–June 2000 |title=River Rules: The Nature of Streams |url=http://www.forester.net/ec_0005_river.html |archive-url=https://web.archive.org/web/20050101180523/http://www.forester.net/ec_0005_river.html |archive-date=2005-01-01 |magazine=Erosion Control Magazine |url-status=usurped |page=5}}</ref>

==Military== In military usage of debouch: as a noun, a fortification at the end of a defile is sometimes known as a debouch; and as a verb, soldiers emerging from a narrow space and spreading out are also said to "debouch".<ref>{{Cite web |title=debouch as a verb |url=http://www.oed.com/view/Entry/47919#eid7298094 |access-date=2012-10-10 |website=Oxford English Dictionary}}</ref>

==References== {{reflist}}

==External links== {{Sister project links  |1= |collapsible= |display=Debouch |position= |style=

|wikt= debouch|c= Debouch |commonscat= |n= no |q= no |s= no |author=no |b=no |v=no

|voy= no |d= Q4156318|m=no |mw= no |species= no |species_author=no }} *{{Cite web |title=debouch |url=http://www.merriam-webster.com/dictionary/debouch |access-date=2012-10-10 |website=Merriam-Webster}}

Category:Fluvial landforms Category:Rivers Category:Water streams Category:Military terminology