Ten Ways Mount St. Helens Changed Our World—The Enduring Legacy of the 1980 Eruption

Fact Sheet 2020-3031
Prepared in cooperation with the U.S. Forest Service and Washington State Parks and Recreation Commission
By: , and 



Mount St. Helens was once enjoyed for its serene beauty and was considered one of America’s most majestic volcanoes because of its perfect cone shape, similar to Japan’s beloved Mount Fuji. Nearby residents assumed that the mountain was solid and enduring. That perception changed during the early spring of 1980. Then, on May 18, 1980, following 2 months of earthquakes and small explosions, the volcano’s over-steepened north flank collapsed in a colossal landslide and triggered a near-horizontal blast, followed by a powerful vertical eruption. The high-speed, rock-filled, and gas-charged blast quickly evolved into a gravitationally driven pyroclastic flow, which leveled millions of trees, stripped them of their branches and bark, and scoured soil from bedrock. The vertical eruption that followed fed a towering plume of ash for more than 9 hours. Winds carried the ash from the volcano and deposited it hundreds of miles away. Lahars (volcanic mudflows) buried river valleys. These catastrophic events caused the worst volcanic disaster in the recorded history of the conterminous United States. The events violently transformed Mount St. Helens and left a lasting impression on the hearts and minds of people living in the Pacific Northwest and beyond.

Suggested Citation

Driedger, C.L., Major, J.J., Pallister, J.S., Clynne, M.A., Moran, S.C., Westby, E.G., and Ewert, J.W., 2020, Ten ways Mount St. Helens changed our world—The enduring legacy of the 1980 eruption: U.S. Geological Survey Fact Sheet 2020-3031, 6 p., https://doi.org/10.3133/fs20203031.

ISSN: 2327-6932 (online)

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Ten ways Mount St. Helens changed our world—The enduring legacy of the 1980 eruption
Series title Fact Sheet
Series number 2020-3031
DOI 10.3133/fs20203031
Year Published 2020
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Volcano Hazards Program
Description 6 p.
Country United States
State Washington
Other Geospatial Mount St. Helens
Google Analytic Metrics Metrics page
Additional publication details