The action of water in arid regions
311
Figure 13.29. Break in the longitudinal profile (knickpoint) caused by differential erosion of a thick bank
of Cretaceous limestones that are more resistant to erosion. One may also observe the basal undermining
caused by the waterfall, Nahel Zin Canyon, Negev Desert, Israel.
+1.0
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Flow of July 5, 1962
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Year 1962
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2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
Distance downstream from watershed divide, thousands of feet
Figure 13.30. Location sketch map of Arroyo de los Frijoles near Santa Fe, New Mexico. Net change
of bed elevation during various periods (after Leopold et al. (1966)).