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Climatic Geomorphology
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Frost-riven cliffs
Small surfaces of I ~
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cryoplanation ~
i valley floo~
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Congelifractate-covered 1
surface of downwasting
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Figure 8.32. The periglacial cycle of erosion. (A) Youth, (B) Maturity, (C) Senility (following Peltier,
1950, in Small, 1970, Figure 6.5). (A) Initial surface, Scarps affected by frost shattering, Cryoplanation
surfaces, Aggradation valley. (B) Large cryoplanation surfaces. (C) Surface mantles with frost-shattered
clasts.