Eur. Phys. J. E (2004) 13: 213-219
https://doi.org/10.1140/epje/e2004-00055-x

Granular size segregation in underwater sand ripples

¹ Physique et Mécanique des Milieux Hétérogénes (PMMH), UMR CNRS-ESPCI 7636, 10 rue Vauquelin, 75231, Paris Cedex 05, France
² Group for Research and Applications in Statistical Physics (GRASP), Institut de Physique B5, Université de Liége, 4000, Liége, Belgium

^* e-mail: herve.caps@ulg.ac.be

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.