James L. Best, 1987. "Flow Dynamics at River Channel Confluences: Implications for Sediment Transport and Bed Morphology", Recent Developments in Fluvial Sedimentology, Frank G. Ethridge, Romeo M. Flores, Michael D. Harvey
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Flow dynamics at river channel confluences can be characterized by six major regions of flow stagnation, flow deflection, flow separation, maximum velocity, flow recovery and distinct shear layers. The dominant controls upon the magnitude of these regions are shown to be the junction angle and the ratio of discharges between the confluent channels. Through the combined use of scaled laboratory modelling and an analysis of field evidence, the dynamics of flow are found to produce a confluence morphology which consists of avalanche faces at the mouth of each confluent channel, a deep central scour and a bar within the separation zone. Tracing of sediment in both laboratory and natural channels reveals distinct sediment pathways within the junction which can be explained through the model of flow dynamics. A knowledge of confluence flow dynamics is important when assessing channel design criteria, junction bed morphology and ancient confluence sediments.
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Recent Developments in Fluvial Sedimentology
This volume brings together 36 of the manuscripts that were presented at the Third International Fluvial Sedimentology Conference hosted by Colorado State University in August, 1985. Fluvial systems and sedimentary rock sequences discussed range in age from Holocene to Precambrian and include many diverse areas. The principal objective of the volume was to document the recent developments in the application of facies analysis to the reconstruction of the architecture of fluvial systems. Reconstruction of architecture is an integral part of the overall process of basin analysis.