Page 463 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

14.3
ANATOMY OF A SLOPE
Hillslopes typically develop a structure made up of several elements: a convex waxing slope, rock outcrop, debris slope, and concave waning slope. One main process predominates on each part of a hillslope: physical and chemical weathering on the upper slope, transportation on the debris slope, and deposition on the lower, waning slope.
Rock outcrop (free face):
The rock outcrop interrupts the slope. Frost wedging loosens rock fragments from the outcrop to form the debris slope.
Soil processes
Physical
and chemical weathering
Transportation
Debris slope
Waxing slope (convex surface)
Free face
Resistant rock
Coarse materials
Deposition
[Bobbè Christopherson.]
Waning slope
(concave surface)
Predict: What will eventually happen to the coarse materials on the debris slope?
Fine materials
Many slope elements are visible in this scene from the Gros Ventre Range, Wyoming.
Locate some of the named features in
the illustration above and in GIA 14.2. [Bobbé Christopherson.]
GEOquiz
1. Explain: Explain how an exogenic event results in a rock particle’s movement down a hillslope. Refer to the forces and energy types shown in GIA 14.2 in your answer.
2. Apply: Is the slope in GIA 14.3 at its angle of equilibrium? Explain your answer, referring to specific parts of the slope and the processes that affect them.
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geosystems in action 14Hillslopes As open systems