Mount Hood
Find U.S. Volcano
Mount Hood volcano, Oregon's highest peak, forms a prominent backdrop to the state's largest city, Portland, and contributes valuable water, scenic, and recreational resources that help sustain the agricultural and tourist segments of the economies of surrounding cities and counties.
Quick Facts
Location: Oregon, Clackamas/Hood River Counties
Latitude: 45.374° N
Longitude: 121.695° W
Elevation: 3,426 (m) 11,240 (f)
Volcano type: Stratovolcano
Composition: Andesite to Dacite
Most recent eruption: 1865 AD
Threat Potential: Very High*
*based on the National Volcano Early Warning System
Summary
Mount Hood has erupted episodically for about 500,000 years and hosted two major eruptive periods during the past 1,500 years. During both recent eruptive periods, growing lava domes high on the southwest flank collapsed repeatedly to form pyroclastic flows and lahars that were distributed primarily to the south and west along the Sandy River and its tributaries. The last eruptive period began in AD 1781 and affected the White River as well as Sandy River valleys. The Lewis and Clark Expedition explored the mouth of the Sandy River in 1805 and 1806 and described a river much different from today's Sandy. At that time the river was choked with sediment generated by erosion of the deposits from the eruption, which had stopped about a decade before their visit. In the mid-1800's, local residents reported minor explosive activity, but since that time the volcano has been quiet.
News
Monitoring stations detect small magnitude earthquakes at Mount Hood (December 8-13, 2023)
Mount Hood's June 5, 2021 Earthquake
M3.9 earthquake and swarm occur at Mount Hood on June 5, 2021
Publications
2018 update to the U.S. Geological Survey national volcanic threat assessment
When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by the U.S. Geological Survey and its partners. This update
