Volcano 06 / 10
Mount St. Helens
The 1980 lateral blast transformed a Cascade peak and modern volcanology.
- Form
- Stratovolcano
- Elevation
- 2,549 m
- Last known eruption
- 2008
- GVP number
- 321050
A magnitude 5.1 earthquake triggered collapse of the unstable north flank on 18 May 1980. The resulting depressurization produced a lateral blast—not a conventional vertical eruption alone.
Tectonic setting
Cascade arc above Juan de Fuca plate subduction beneath North America.
Membership note
Included in the current Smithsonian PROF regional definition.
18 May eruption
Landslide, lateral blast, ash column, and lahars caused severe regional impacts.
This is a curated profile excerpt, not the complete eruption catalog. Historical year, month, and day fields remain nullable in the analytical database.
Claim-level values in this profile resolve to the source below. Dataset membership and narrative interpretation are stored separately.