Settling-velocity distributions and sorting processes on a longitudinal dune: A case study |
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| Authors: | Daniel Hartmann Christian Christiansen |
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| Abstract: | The processes acting on a longitudinal dune are inferred from the response in the area size-sorting characteristics of the sediment of the active layer. The sediment size distributions are determined by settling and are best described by a log-hyperbolic model which provides the most information on size-sorting processes. Size-sorting characteristics are markedly different across the low round-crested part of the dune from cross-sections of the high more sharp-crested part. This results in changes in textural parameters along the lee-side consistent with changes in the lee-side separation vortex. This is the first time that the effect of wind speed up on the lee-side is observed to be reflected in the sediment; it can only be detected with the very sensitive log-hyperbolic parameters. |
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| Keywords: | Log-hyperbolic distribution Log-hyperbolic shape triangle Sorting processes Separation vortex Wind speed up Seif dune |
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