Mount Bachelor

Find U.S. Volcano

At 2,764 meters (9,068 feet) high, Mount Bachelor is the prominent peak just south of the Three Sisters in central Oregon.

Quick Facts

Location: Oregon, Deschutes County

Latitude: 43.979° N

Longitude: 121.688° W

Elevation: 2,764 (m) 9,068 (f)

Volcano type: Stratovolcano

Composition: Basalt to Andesite

Most recent eruption: About 9,500 years ago

Threat Potential: Moderate*

_{*based on the National Volcano Early Warning System}

Summary

It is located within the Deschutes National Forest, 20 km west-southwest of Bend, Oregon. Mount Bachelor is the largest volcano in the 25-km-long, north-south trending, Mount Bachelor volcanic chain, which is composed of numerous cinder cones, lava flows, and shield volcanoes and covers and area of nearly 250 km² (100 mi²). Eruptions of the chain began during or closely following the retreat of late Pleistocene glaciers (after about 18 ka) and ended before the eruption of Mount Mazama (Crater Lake at 7.7 ka), with the main pulse of activity lasting perhaps only 3,000 years. The volcanic chain produced mainly lava flows and near-vent tephra falls. The chain is typical of one style of mafic (basalt to andesite) volcanism found throughout the Cascades Volcanic Arc—effusive eruptions from aligned short-lived volcanic vents.

Publications

October 22, 2018

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

Authors

John W. Ewert, Angela K. Diefenbach, David W. Ramsey

Volcano Hazards Program, Volcano Science Center, Agrigan, Ahyi Seamount, Alamagan, Anatahan, Asuncion, Belknap, Black Butte Crater Lava Field, Black Rock Desert Volcanic Field, Blue Lake Crater, Carrizozo Lava Flow, Cascade Range Weekly Update, Cinnamon Butte, Clear Lake Volcanic Field, Coso Volcanic Field, Crater Lake, Craters of the Moon Volcanic Field, Daikoku Seamount , Davis Lake Volcanic Field, Devils Garden Lava Field, Diamond Craters Volcanic Field, Dotsero Volcanic Center, East Diamante, Esmeralda Bank, Farallon de Pajaros, Fukujin Seamount , Glacier Peak, Guguan, Haleakalā, Hell's Half Acre Lava Field, Hualālai, Indian Heaven Volcanic Field, Jordan Craters Volcanic Field, Kama‘ehuakanaloa, Kasuga 2, Kīlauea, Lassen Volcanic Center, Long Valley Caldera, Mammoth Mountain, Markagunt Plateau Volcanic Field, Maug Islands, Mauna Kea, Mauna Loa, Medicine Lake, Mono Lake Volcanic Field, Mono-Inyo Craters, Mount Adams, Mount Bachelor, Mount Baker, Mount Hood, Mount Jefferson, Mount Rainier, Mount Shasta, Mount St. Helens, Newberry, Ofu-Olosega, Pagan, Red Hill-Quemado Volcanic Field, Ruby, Salton Buttes, San Francisco Volcanic Field, Sand Mountain Volcanic Field, Sarigan, Soda Lakes, South Sarigan Seamount, Supply Reef, Ta'u Island, Three Sisters, Tutuila Island, Ubehebe Craters, Uinkaret Volcanic Field, Valles Caldera, Wapi Lava Field, Weekly Update, West Crater Volcanic Field, Yellowstone, Zealandia Bank, Zuni-Bandera Volcanic Field

January 1, 1994

Temporal, spatial and petrologic variations of lava flows from the Mount Bachelor volcanic chain, central Oregon High Cascades

No abstract available.

Authors

Cynthia A. Gardner

Mount Bachelor

January 1, 1989

Guidebook for field trip to the Mount Bachelor-South Sister-Bend area, central Oregon High Cascades

No abstract available.

Authors

William E. Scott, Cynthia A. Gardner, Scott A. Lundstrom, Brittain E. Hill, Edward M. Taylor, Andrei M. Sarna-Wojcicki, Charles E. Meyer, John K. Nakata, J.L. Slate, P.C. Russell

Volcano Hazards Program, Volcano Science Center, Mount Bachelor

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Science

Map showing one-year probability of accumulation of 1 centimeter

October 24, 2023

Hazards Summary for Mount Bachelor

Although Mount Bachelor looks similar to many of the more long-lived and potentially dangerous volcanic peaks of the Cascade Range, the mountain is part of a mafic volcanic chain that poses little danger for future eruptive activity.

Cascades Volcano Observatory, Mount Bachelor

October 24, 2023