By its very nature, the
production of siliciclastic sediment destroys much of the direct evidence of
its source region, so geoscientists are left with indirect tools to assess
metrics such as catchment basin size. In this paper, Davidson and Hartley
relate the areal extent of existing large (> 30 km in length) distributive
fluvial systems (DFS) formed in endorheic basins to contributing drainage basin
area. Regression analyses indicate a strong positive relationship between
drainage area and DFS area; additionally, drainage basin relief influences
sediment supply in terms of volume or caliber, which in turn affects the
depositional gradient of the DFS surface and resultant channel planform.
Application of these regression relationships to examples in the rock record
shows that DFS area can be used as a proxy to predict the surface area of
fluvially transported sediment deposited in a sedimentary basin from the
contributing catchment. The modern regression relationships suggest a
measurable link between source and sink in the sedimentary rock record, and
provide a potential tool for more accurate prediction of preserved fluvial
architecture within basin-scale climatic and tectonic contexts.
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