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Lahars and their deposits

December 31, 2015

Lahars occur during volcanic eruptions--or, less predictably, through other processes on steep volcanic terrain--when large masses of water mixed with sediment sweep down and off volcano slopes and commonly incorporate additional sediment and water. Because lahars are water-saturated, both liquid and solid interactions influence their behavior and distinguish them from other related phenomena common to volcanoes, such as debris avalanches and floods. The rock fragments carried by lahars make them especially destructive; the abundant liquid contained in them allows them to flow over gentle gradients and inundate areas far away from their sources. People in such distal areas commonly neither expect the danger nor anticipate the destructive power of lahars.

Publication Year 2015
Title Lahars and their deposits
DOI 10.1016/B978-0-12-385938-9.00037-7
Authors James W. Vallance, Richard M. Iverson
Publication Type Book Chapter
Publication Subtype Book Chapter
Index ID 70193636
Record Source USGS Publications Warehouse
USGS Organization Volcano Science Center