alluvial fan

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alluvial fan

A fan-shaped accumulation of alluvium deposited at the mouth of a ravine or at the juncture of a tributary stream with the main stream.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

alluvial fan


alluvial cone

(Geological Science) a fan-shaped accumulation of silt, sand, gravel, and boulders deposited by fast-flowing mountain rivers when they reach flatter land
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

allu′vial fan′

a fan-shaped alluvial deposit formed by a stream where its velocity is abruptly decreased, as at the mouth of a ravine.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

al·lu·vi·al fan

A fan-shaped mass of sediment, especially silt, sand, gravel, and boulders, deposited by a river when its flow is suddenly slowed. Alluvial fans typically form where a river pours out from a steep valley through mountains onto a flat plain. Unlike deltas, they are not deposited into a body of standing water.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.alluvial fan - a fan-shaped deposit where a fast flowing stream flattens out
geological phenomenon - a natural phenomenon involving the structure or composition of the earth
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The water, he said reached Botswana in April and started to spread throughout the alluvial fan slowly filling up the channels, backflows and floodplains.
The problem is simply that the Delta is not renewing itself because the Mississippi is so ditched, dammed, diked and degraded it doesn't dump its sediment load into a vast marsh anymore, renewing it, instead spewing it into the Gulf through one large channel onto one great alluvial fan.
The chemical components of the groundwater in the middle and upper parts of the alluvial fan are not significantly different from those of the river water.
In reaction, Project NOAH compiled all 'alluvial fan areas' in the country, with more than 1,200 alluvial fans identified throughout the country.
And topography is broken down into mountainous areas, fluvial plains, valley areas, hilly areas, alluvial fan areas, piedmont slope areas, and diluvium areas.
Within the walls of Acopios 1 and Acopios 2 a high angle (subvertical), south-dipping fault zone affecting alluvial fan deposits can be seen (Figs.
It sits in the middle of an alluvial fan and represents a true taste of Rutherford dust."
If you were to stand atop a high mountain in the northeast of Taiwan and look out over the expanse of Yilan County below, you would see an alluvial fan spreading out toward the sea, bracketed by hill and mountain that has been formed over eons by the steady rush of the Lanyang River and other local waterways.
Multiple contributions from Yangtze University propose an algorithm for analyzing the particle size of gravel from images, apply a truncated Gaussian simulation algorithm to an alluvial fan reservoir, and estimate the best number of data points for Kriging interpolation.
Snow Creek is a tiny village off of Highway 111 near I-10 nestled on an alluvial fan at the foot of the San Jacinto Mountains.