R. Bruce King, 2008. "South African pediments and interfluves", Landscape Evolution: Denudation, Climate and Tectonics over Different Time and Space Scales, K. Gallagher, S. J. Jones, J. Wainwright
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From fifty 1:50,000 scale topographic maps of South Africa, the following attributes were recorded at every intersection of one minute longitude and latitude: basic land facet description, annual rainfall, rainfall concentration, rainfall seasonality, monthly rainfall, local relief, contour interval, rock type, vegetation, pediment length or interfluve width, stream order at valley bottom, local drainage pattern, altitude, terrain morphology, physiographic region and postulated age of planation surface as defined by King (The Morphology of the Earth: a Study and Synthesis of World Scenery, Oliver & Boyd, 1962) and Partridge & Maud (South African Journal of Geology, 90, 179–208, 1987). A strong relationship was found between the propensity for concave slopes (or escarpments) where there is low annual rainfall and high local relief. The relationship with rock type was not so strong, but concave slopes are shown to be more likely on fine-textured rather than coarser-textured rock types. The relationship between drainage density and annual rainfall decreases in value from less than 200 mm annual rainfall up to 400–600 mm annual rainfall, and then increases above this value. Concave slopes are particularly prone in lightly vegetated areas, require some local relief, and are more common on easily eroded rocks and older land surfaces protected from recent drainage dissection. Sheetwash seems the most likely agent of erosion.
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Landscape Evolution: Denudation, Climate and Tectonics over Different Time and Space Scales
The morphology of Earth’s surface reflects the interaction of climate, tectonics and denudational processes operating over a wide range of spatial and temporal scales. These processes can be considered catastrophic or continuous; depending on the timescale of observation or interest. Recent research had required integration of historically distinct subjects such as geomorphology, sedimentology, climatology and tectonics. Together, these have provided new insights into absolute and relative rates of denudation, and the factors that control the many dynamic processes involved. Specific subject areas covered are sediment transport processes and the timescales of competing processes, the role of the geological record and landscapes in constraining different processes, the nature of landscape evolution at different spatial scales and in contrasting geological environments.