Water fact sheet, history of landslides and debris flows at Mount Rainier

Open-File Report 93-111
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Many landslides and debris flows have originated from Mount Rainier since the retreat of glaciers from Puget Sound about 10,000 years ago. The recurrent instability is due to several factors--height of the steep-sided volcanic cone, frequent volcanic activity, continuous weakening of rock by steam and hot, chemical-laden water, and exposure of unstable areas as the mountains glaciers have receded. The landslide scars and deposits tell a fascinating story of the changing shape of the volcano. Landslides occur when part of the volcano "collapses" or fails and slides away from the rest of the volcano. The failed mass rapidly breaks up into a jumble of disaggregated pieces that flow at high velocity like a fluid. Clay and water in the debris cause further change to a liquid slurry known as a debris flow or mudflow. Volcanic debris flows are also widely known by the Indonesian term "lahar." Although the largest debris flows at Rainier form from landslides, many smaller flows are caused by volcanic eruptions, intense rainfall, and glacial-outburst floods.

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Publication type Report
Publication Subtype USGS Numbered Series
Title Water fact sheet, history of landslides and debris flows at Mount Rainier
Series title Open-File Report
Series number 93-111
DOI 10.3133/ofr93111
Year Published 1993
Language English
Publisher U.S. Geological Survey
Publisher location Vancouver, WA
Contributing office(s) Volcano Science Center
Description 2 p.
Country United States
State Washington
Other Geospatial Mount Rainier
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
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