Article Dans Une Revue Earth Surface Dynamics Année : 2016

Geometry of meandering and braided gravel-bed threads from the Bayanbulak Grassland, Tianshan, P. R. China

Résumé

The Bayanbulak Grassland, Tianshan, P. R. China, is located in an intramontane sedimentary basin where meandering and braided gravel-bed rivers coexist under the same climatic and geological settings. We report and compare measurements of the discharge, width, depth, slope and grain size of individual threads from these braided and meandering rivers. Both types of threads share statistically indistinguishable regime relations. Their depths and slopes compare well with the threshold theory, but they are wider than predicted by this theory. These findings are reminiscent of previous observations from similar gravel-bed rivers. Using the scaling laws of the threshold theory, we detrend our data with respect to discharge to produce a homogeneous statistical ensemble of width, depth and slope measurements. The statistical distributions of these dimensionless quantities are similar for braided and meandering threads. This suggests that a braided river is a collection of intertwined threads, which individually resemble those of meandering rivers. Given the environmental conditions in Bayanbulak, we furthermore hypothesize that bedload transport causes the threads to be wider than predicted by the threshold theory.

Fichier principal
Vignette du fichier
esurf-4-273-2016.pdf (3.99 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte
Licence
Loading...
HAL

Est une version de hal-01499421 Article François Métivier, Olivier Devauchelle, Hugo Chauvet, Eric Lajeunesse, Patrick Meunier, et al.. Geometry of meandering and braided gravel-bed threads from the Bayanbulak Grassland, Tianshan, P. R. China. Earth Surface Dynamics, 2016, 4 (1), pp.273-283. ⟨10.5194/esurf-4-273-2016⟩. ⟨hal-01499421⟩

entrée dupliquée

Dates et versions

hal-01499421 , version 1 (31-03-2017)

Licence

Identifiants

Citer

François Métivier, Olivier Devauchelle, Hugo Chauvet, Eric Lajeunesse, Patrick Meunier, et al.. Geometry of meandering and braided gravel-bed threads from the Bayanbulak Grassland, Tianshan, P. R. China. Earth Surface Dynamics, 2016, 4 (1), pp.273-283. ⟨10.5194/esurf-4-273-2016⟩. ⟨hal-01499421⟩
381 Consultations
435 Téléchargements

Altmetric

Partager

  • More