Stanley A. Schumm, 1981. "Evolution and Response of the Fluvial System, Sedimentologic Implications", Recent and Ancient Nonmarine Depositional Environments: Models for Exploration, Frank G. Ethridge, Romeo M. Flores
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A fluvial system ideally has three main components: 1) a drainage basin, the sediment and water source area, 2) a river, the conduit which removes the waste of the drainage basin, and 3) a site of sediment deposition in a piedmont or coastal zone.
The nature and quantity of sediment produced from the source area determines the morphologic character of the river, and a river can be classified into five patterns dependent on type of sediment load. The 1) straight and the 2) sinuous-thalweg patterns reflect relatively low values of sediment transport, of bed-load to total-load ratio, and of stream power. The 3) meandering pattern reflects relatively low to moderate values of sediment transport, of bed-load to total-load ratio, and of stream power. The 4) meandering-braided transitional pattern and the 5) braided pattern reflect relatively high values of sediment transport, of bed-load to total-load ratio, and of stream power.
Throughout geologic time fluvial systems have had complex erosional and sediment-production histories as a result of external and internal influences. The external variables that most significantly affect the fluvial system are tectonic, eustatic and climatic. The internal variables are geomorphic. The response of the fluvial system to changes in these controls is complex involving both erosion and deposition.
The morphologic character of a river and its associated sediments change, as the character of the sediment delivered from the source area changes. The character of sedimentary deposits (piedmont, deltaic or near-shore) reflect the geology, morphology and erosional history of the source area as well as the type of river transporting the sediment. Abrupt changes in amount and type of sediment reflect not only the complexity of the erosional evolution of the area, but also the dynamics of the sediment producing and transport zones of the fluvial system.