362
Climatic Geomorphology
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--uw~r,al,
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nt
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X Zone of coalescence
1with other fans
Apex
1
5 KM
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150
100
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a
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Radial profile A-A'
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Vertical exaggeration x 53
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10
SCALE IN KM
Figure 15.19. Typical segmentation and longitudinal profile of an alluvial fan. Example from the Tumey
Gulch fan, western Fresno County, California (Bull, 1964a).
the capture of the incised channel and promoting the downslope shift of the active
depositional lobes (Denny, 1967).
Because the depositional processes are strongly controlled by the sediment supply on to
the fan surface (Harvey, 1997), the bulk morphology of an individual fan should reflect the
main characteristics of its source area. Many of the studies on the morphology of alluvial
fans are based on the analyses of morphometric variables, such as fan shape, fan area and
fan gradient (slope).