Landslides - 23 of 22
Landslides FAQs - 22 Found
The world's biggest historic landslide occurred during the 1980 eruption of Mount St. Helens, a volcano in the Cascade Mountain Range in the State of Washington, USA. The volume of material was 2.8 cubic kilometers (km).
The world's biggest prehistoric landslide, discovered so far on land, is in southwestern Iran, and is named the Saidmarreh landslide. The landslide is located on the Kabir Kuh anticline in Southwest Iran at 33 degrees north latitude, 47.65 degrees east longitude. The landslide has a volume of about 20 cubic kilometers, a depth of 300 m, a travel distance of 14 km and a width of 5 km. This means that about 50 billion tons of rock moved in this single event!
Sources of Information:
Harrison, J. V., and Falcon, N.L., 1938, An Ancient Landslip at Saidmarreh in Southwestern Iran, The Journal of Geology, Vol. 46, No. 3, Part I (Apr. - May, 1938), pp. 296-309, The University of Chicago Press.
Schuster, Robert L., and Lynn M. Highland, 2001, Socioeconomic Impacts of Landslides in the Western Hemisphere, U.S. Geological Survey Open-File Report 01-0276.
USGS Cascades Volcano Observatory Web site.