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dune bedform

dune bedform (‘megaripples’) Mounds or ridges of sand which are asymmetrical, and are produced subaqueously by flowing water. The external morphology is similar to the smaller ‘ripple’ and larger ‘sand wave’, with a gently sloping, upstream side (stoss), and a steeper downstream side (lee). The crestline elongation extends transverse to the flow direction and is sinuous or lunate in plan. The height varies between 0.1 m and 2 m, while the wavelength (spacing) between dunes is 1–10 m. Size and growth are limited by water depth and, in general, dune height is less than one-sixth of the flow depth. The down-current migration of dune bedforms leads to the formation of cross-bedding in sediments.

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"dune bedform." A Dictionary of Earth Sciences. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"dune bedform." A Dictionary of Earth Sciences. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/dune-bedform

"dune bedform." A Dictionary of Earth Sciences. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/dune-bedform

dune bedform

dune bedform(‘megaripples’) Mounds or ridges of sand which are asymmetrical and are produced subaqueously by flowing water. The external morphology is similar to the smaller ‘ripple’ and larger ‘sand wave’, with a gently sloping, upstream side (stoss), and a steeper downstream side (lee). The crestline elongation extends transverse to the flow direction and is sinuous or lunate in plan. The height varies between 0.1 m and 2 m, while the wavelength (spacing) between dunes is 1–10 m. Size and growth are limited by water depth and, in general, dune height is less than one-sixth of the flow depth. The down-current migration of dune bedforms leads to the formation of cross-bedding in sediments.

Cite this article
Pick a style below, and copy the text for your bibliography.

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"dune bedform." A Dictionary of Ecology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"dune bedform." A Dictionary of Ecology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/dune-bedform-0

"dune bedform." A Dictionary of Ecology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/dune-bedform-0