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Posteruption glacier development within the crater of Mount St. Helens, Washington, USA

Published online by Cambridge University Press:  20 January 2017

Steve P. Schilling*
Affiliation:
U.S. Geological Survey, 1300 SE Cardinal Court, Vancouver, WA 98683, USA
Paul E. Carrara
Affiliation:
U.S. Geological Survey, Mail Stop 980, Denver Federal Center, Denver, CO 80225, USA
Ren A. Thompson
Affiliation:
U.S. Geological Survey, Mail Stop 980, Denver Federal Center, Denver, CO 80225, USA
Eugene Y. Iwatsubo
Affiliation:
U.S. Geological Survey, 1300 SE Cardinal Court, Vancouver, WA 98683, USA
*
*Corresponding author. Fax: (360) 993-8980.E-mail address:sschilli@usgs.gov (S.P. Schilling).

Abstract

The cataclysmic eruption of Mount St. Helens on May 18, 1980, resulted in a large, north-facing amphitheater, with a steep headwall rising 700 m above the crater floor. In this deeply shaded niche a glacier, here named the Amphitheater glacier, has formed. Tongues of ice-containing crevasses extend from the main ice mass around both the east and the west sides of the lava dome that occupies the center of the crater floor. Aerial photographs taken in September 1996 reveal a small glacier in the southwest portion of the amphitheater containing several crevasses and a bergschrund-like feature at its head. The extent of the glacier at this time is probably about 0.1 km2. By September 2001, the debris-laden glacier had grown to about 1 km2 in area, with a maximum thickness of about 200 m, and contained an estimated 120,000,000 m3 of ice and rock debris. Approximately one-third of the volume of the glacier is thought to be rock debris derived mainly from rock avalanches from the surrounding amphitheater walls. The newly formed Amphitheater glacier is not only the largest glacier on Mount St. Helens but its aerial extent exceeds that of all other remaining glaciers combined.

Type
Short Paper
Copyright
University of Washington

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References

Barry, R.G, Chorley, R.J, (1976). Atmosphere, Weather, and Climate. third ed. Methuen, London.Google Scholar
Brugman, M.M, Post, A, (1981). Effects of volcanism on the glaciers of Mount St. Helens. U.S. Geological Survey Circular. 850-D, .Google Scholar
Lundstrom, S.C, McCafferty, A.E, Coe, J.A, (1993). Photogrammetric analysis of 1984–89 surface altitude change of the partially debris-covered Eliot Glacier, Mount Hood, Oregon, U.S.A.. Annals of Glaciology. 17, 167170.Google Scholar
Mills, H.H, (1992). Post-eruption erosion and deposition in the 1980 crater of Mount St. Helens, Washington, determined from digital maps. Earth Surface Processes and Landforms. 17, 739754.CrossRefGoogle Scholar
Muller, E.H, Coulter, H.W, (1957). Incipient glacier development within Katmai Caldera, Alaska. Journal of Glaciology. 3, 1317.Google Scholar
Swanson, D.A, Holcomb, R.T, (1990). Regularities in growth of the Mount St. Helens dacite dome, 1980–1986. Fink, J, The Mechanics of Lava Flow Emplacement and Dome Growth. International Association of Volcanology and Chemistry of the Earth's Interior. Proceedings in Volcanology. vol. 2, Springer-Verlag, Berlin., 324.Google Scholar
Thompson, R.S., Schilling, S.P., in press. Photogrammetry. In: Dzurisin, D., (Ed.), Volcano Geodesy: Exploring Unstable Ground, Praxis, Chichester, UK.Google Scholar