A simple model of bedform migration
Article first published online: 10 JUN 2010
Copyright © 2010 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 35, Issue 10, pages 1211–1220, August 2010
How to Cite
Bartholdy, J., Ernstsen, V.B., Flemming, B.W., Winter, C. and Bartholomä, A. (2010), A simple model of bedform migration. Earth Surf. Process. Landforms, 35: 1211–1220. doi: 10.1002/esp.2002
- Issue published online: 20 JUL 2010
- Article first published online: 10 JUN 2010
- Manuscript Accepted: 25 JAN 2010
- Manuscript Revised: 19 JAN 2010
- Manuscript Received: 24 OCT 2008
- dune migration;
- bedload model;
- incipient motion
A model linking subaqueous dune migration to the effective (grain related) shear stress is calibrated by means of flume data for bedform dimensions and migration rates. The effective shear stress is calculated on the basis of a new method assuming a near-bed layer above the mean bed level in which the current velocity accelerates towards the bedform crest. As a consequence, the effective bed shear stress corresponds to the shear stress acting directly on top of the bedform. The model operates with the critical Shields stress as a function of grain size, and predicts the deposition (volume per unit time and width) of naturally-packed bed material on the bedform lee side, qbcrest. The model is simple, built on a rational description of simplified sediment mechanics, and its calibration constant can be explained in accordance with estimated values of the physical constants on which it is based. Predicted values of qbcrest correlate with measured values of bedform height multiplied by bedform migration rate with R2 = 0·83. Copyright © 2010 John Wiley & Sons, Ltd.