Adams
Stratovolcano in United States
Key Facts
Elevation
3,742 m (12,277 ft)
Type
Stratovolcano
Location
46.206°, -121.490°
Region
High Cascades Volcanic Arc
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
The andesitic-dacitic Mount Adams stratovolcano is second in volume only to Mount Shasta in the Cascade Range. The volcanic complex is elongated along a NNW-SSE line, and includes more than 60 flank vents over 200 km2. Volcanism began about 940 ka, with three main cone-building stages occurring at about 500, 450, and 30 ka.
It was active throughout the Holocene, producing two dozen minor explosive eruptions from summit and flank vents. Six Holocene lava flows are located on the flanks between 2,100 and 2,600 m elevation. The most voluminous Holocene lava flows, some of which traveled 10 km or more, were emplaced between about 7,000 and 4,000 years ago.
The latest eruption about 1,000 years ago produced a minor tephra layer and possibly a small lava flow down the E flank.
Volcanic Hazards & Risk Assessment
Primary Hazards
- Pyroclastic flows
- Lava flows
- Volcanic bombs and ballistics
- Lahars and mudflows
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | Unknown | Low | Moderately active volcano |
| Maximum VEI | VEI Unknown | Minor | Local impact potential |
| Recent Activity | 1076 years ago | Historical | Historically active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in North America Volcanic Regions
Quick Info
- •Smithsonian ID: 321040
- •Evidence: Eruption Dated
- •Epoch: Holocene
About the Photo
Mount Adams in the Cascade Range is seen here in 1981 from High Knob to the NW. Its base is at a lower elevation than its neighbor Mount Rainier and it has a larger volume. Numerous flank vents surround the volcano and a series of lava flows have erupted on the N, NW, S and E flanks.
Photo by Lee Siebert, 1981 (Smithsonian Institution).
Authority Sources
Related Volcanoes
Basic Information
This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.