The arid region piedmonts: glacis and alluvial fans
347
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Figure 15.4. Map of the pediments mentioned in the literature (after Whitaker, 1973).
along active tectonic fronts their gradient is steeper than in areas of tectonic quiescence.
There are also relationships between slopegradient and clastsize, in such a way that
when the steeper the slope, larger clastsizes occur. For some authors lithology
is not a relevant factor (Mammerickx, 1964), while others point out its impact on the
Figure 15.5. Inselberg carved in Cambrian sandstones with the development of gently slope radial
pediments. Jodhpur-Jaisalmer region. Semi-arid zone of the Thar Desert (India).