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Mechanics of debris flows and rock avalanches: Chapter 43

January 1, 2012

Debris flows are geophysical phenomena intermediate in character between rock avalanches and flash floods. They commonly originate as water-laden landslides on steep slopes and transform into liquefied masses of fragmented rock, muddy water, and entrained organic matter that disgorge from canyons onto valley floors. Typically including 50%–70% solid grains by volume, attaining speeds >10 m/s, and ranging in size up to ∼109 m3, debris flows can denude mountainsides, inundate floodplains, and devastate people and property (Figure 43.1). Notable recent debris-flow disasters resulted in more than 20,000 fatalities in Armero, Colombia, in 1985 and in Vargas state, Venezuela, in 1999.

Publication Year 2012
Title Mechanics of debris flows and rock avalanches: Chapter 43
DOI 10.1201/b14241-47
Authors Richard M. Iverson
Publication Type Book Chapter
Publication Subtype Book Chapter
Index ID 70193210
Record Source USGS Publications Warehouse
USGS Organization Volcano Science Center