348
Climatic
Geomorphology
Figure 15.6. Segmented hillslope with a succession of convex and concave segments. The relief
terminates in a pediment developed from a concave knick-zone. Machakos, Kenya.
slopegradient (Cooke et al., 1993). Climate seems also to affect glacis gradients, with
smaller glacis slopes in the more arid regions (Mabbutt, 1977).
The channel network of pediments is usually entrenched in the proximal zone, but
channels radiate downslope towards the distal areas, where commonly overland flows
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Figure 15.7. Different elements of the pediment. (A) Dissected zone (up) and inselbergs (down). (B)
Pediment with residual reliefs. (C) Mantled pediment (Johnson, 1932a).