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Abstract
Transport of coarse, heterogeneous debris in a natural stream under a wide range of flows usually results in a remarkably stable, undulatory bed profile, which manifests an in transit sorting process of the bed material. In general, finer material representative of the bulk of the normal bed load resides in the deep sections, or pools, below flood stages. At high flows, pools may scour to immovable boulders or bedrock. Coarser material transported at more infrequent flows forms the shallow sections, or riffles.
Citation
Lisle, Thomas. 1979. A sorting mechanism for a riffle-pool sequence. Geological Society of America Bulletin, Vol. 90. Part II, p. 1142-1157.