On 18 May 1980 an earthquake triggered the largest landslide in recorded history, uncorking a lateral blast that flattened forest for 30 km and killed 57 people — the deadliest eruption in United States history.
Erupted since 2000
Stratovolcano · Dacite
0 events in 90 days
Seismicity within 50 km radius, active VAAC ash plumes, and tectonic plate boundaries.
No catalogued earthquakes within 50 km in the last 90 days.
Mount St. Helens is an active Stratovolcano formed in an active Subduction zone / Continental crust (> 25 km). Dominant lithology: Dacite.
Official catalogue parameters, coordinates, elevation and geotectonic classification.
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Catalogue: Smithsonian Institution, Global Volcanism Program.Smithsonian GVP profile