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Granular size segregation in underwater sand ripples

G. Rousseaux·H. Caps·J. -E. Wesfreid
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Abstract

We report an experimental study of a binary sand bed under an oscillating water flow. The formation and evolution of ripples is observed. The appearance of a granular segregation is shown to strongly depend on the sand bed preparation. The initial wavelength of the mixture is measured. In the final steady state, a segregation in volume is observed instead of a segregation at the surface as reported before. The correlation between this phenomenon and the fluid flow is emphasised. Finally, different ``exotic'' patterns and their geophysical implications are presented.

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G. Rousseaux, H. Caps, J. -E. Wesfreid. 2004-03-29. Granular size segregation in underwater sand ripples. https://doi.org/10.1140/epje%2Fe2004-00055-x

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