Stuart J. Jones, 2002. "Transverse rivers draining the Spanish Pyrenees: large scale patterns of sediment erosion and deposition", Sediment Flux to Basins: Causes, Controls and Consequences, S.J. Jones, L.E. Frostick
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Data collected from six transverse rivers draining the Spanish Pyrenees highlight how the rate of change in river gradients downstream controls long-term deposition and erosion patterns across the mountain belt. The rivers draining the Spanish Pyrenees provide evidence for an important relationship between gradient (S) and distance from the drainage divide (x), such that S is proportional to xΩ. This can be expressed quantitatively as a power function relation S ∝ L~R. In areas dominated by erosion Ω has a value > −5, while in areas of deposition Ω has a value < −0.4. The contrast between areas of erosion and deposition is also reflected in downstream increases and decreases, respectively, in stream power and bed shear stress along the whole of the mountain front.
It is proposed, based upon previous empirical studies of loose to semi-armoured channels, that the downstream variations of stream power and bed shear stress result in variations of bed-load transport rates, which in turn create the erosional and depositional patterns associated with variations of channel gradient.
These results highlight the complex response of the fluvial system, emphasizing the need for regional approaches for examining long-term changes in rivers draining orogenic belts and the importance for incorporation of hydraulic data into geomorphological models to assist interpretations of the mass distribution of sediment.
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There is an increasing trend in the Earth sciences towards the integration of many subdisciplines. The sedimendatry basin, is a fundamental focal point of many studies, which as a consequence often neglects the complimentary drainage basin or catchment. Sedimentary basins provide a record of Earth history, reflecting the geographical, lithological, oceanographic and ecological development through the rock record. Drainage basins in comparison record ephemeral landscape evolution, where topography is eroded and provides the flux of sediment to the basin. The basin fill reflects the sediment flux from the hinterland and provides evidence of the dynamic geomorphic processes. In context the drainage system and sedimentary basin can be regarded as a ‘production line’ with sedimentary record giving valuable insight into long-term landscape evolution and geomorphological processes illuminating the evolution of sedimentary basins.
This volume assesses the current position of understanding sediment supply to basins with the integration of the many sub-disciplines in the Earth sciences. It documents a mix of hinterland and sedimentary basin studies with a gradation from orogenic belts to the deep marine. The authors represent a wide spectrum of Earth scientist, with leaders in the science providing review papers and new-directive papers in their field of specialization.