Vertical mixing of gravel over a long flood series
Version of Record online: 1 MAR 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 36, Issue 8, pages 1044–1058, 30 June 2011
How to Cite
Haschenburger, J. K. (2011), Vertical mixing of gravel over a long flood series. Earth Surf. Process. Landforms, 36: 1044–1058. doi: 10.1002/esp.2130
- Issue online: 25 MAR 2011
- Version of Record online: 1 MAR 2011
- Manuscript Accepted: 13 DEC 2010
- Manuscript Revised: 6 DEC 2010
- Manuscript Received: 31 JAN 2010
- partial sediment transport;
- grain exchange;
- size-selective transport
Vertical sediment exchange is a fundamental component of bedload transport in gravel-bed channels. This paper describes the characteristic depth of exchange achieved over a long flood series. Analysis is based on 11 recoveries of magnetically tagged gravels deployed in Carnation Creek, Canada, completed between 1990 and 2008. Vertical grain exchange mixes gravels throughout the streambed relatively rapidly. Within one to eight floods the mean burial depth approaches two times the surface layer thickness, quantified by the 90th percentile of the size distribution. Finer gravels are mixed more rapidly into the bed than coarser gravels. Both active and passive grain exchanges throughout most of the bed produce the overall vertical distribution of marked grains. Gravel exchanges exhibit fairly consistent patterns once tracers are well mixed by large floods. Results highlight the role of flood sequence in determining exchange depths, support the notion of an upper limit to exchange, and underscore the importance of passive grain exchange. Copyright © 2011 John Wiley & Sons, Ltd.