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San Francisco Volcanic Field

Find U.S. Volcano

Northern Arizona's San Francisco Volcanic Field, which covers about 4,700 square kilometers (1,800 square miles), is an area of young volcanoes along the southern margin of the Colorado Plateau. Much of the field lies within Coconino and Kaibab National Forests.

Quick Facts

Location: Arizona, Coconino County

Latitude: 35.37° N

Longitude: 111.5° W

Elevation: 2,447 (m) 8,028 (f)

Volcano type: volcanic field

Composition: basalt

Most recent eruption: 1085 A.D.

Nearby towns: Flagstaff, Williams

Threat Potential: Moderate*

*based on the National Volcano Early Warning System

Summary

San Francisco Peaks, north of Flagstaff, Arizona
San Francisco Peaks, north of Flagstaff, Arizona, viewed from the northeast. This mountain cluster is the tallest of the San Francisco Volcanic field.

Northern Arizona's San Francisco Volcanic Field, which covers about 4,700 km2 (1,800 mi2), is an area of young volcanoes along the southern margin of the Colorado Plateau. Much of the field lies within Coconino and Kaibab National Forests. During its approximately 6-million-year history, this field has produced more than 600 volcanoes, and almost all of the hills and mountains between Flagstaff and the Grand Canyon are representative of the San Francisco Volcanic Field. The most prominent landmark is San Francisco Mountain, a stratovolcano that rises to 3,850 m (12,633 ft) and serves as a scenic backdrop to the city of Flagstaff. Sunset Crater, the State's youngest volcano, erupted in about A.D. 1085 and must have been witnessed by native inhabitants who lived very nearby. Sunset Crater Volcano National Monument was founded in 1930 to protect the cinder cone and associated lava flow.

News

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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

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

Science

Geology and History of San Francisco Volcanic Field

The first volcanoes in the San Francisco Volcanic Field began to erupt about 6 million years ago, in an area where the town of Williams is now. Subsequently, a several-mile-wide belt of successively younger eruptions migrated eastward, to the area of modern Flagstaff, and beyond toward the valley of the Little Colorado River. Today, this belt of volcanoes extends about 50 miles from west to east.
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Geology and History of San Francisco Volcanic Field

The first volcanoes in the San Francisco Volcanic Field began to erupt about 6 million years ago, in an area where the town of Williams is now. Subsequently, a several-mile-wide belt of successively younger eruptions migrated eastward, to the area of modern Flagstaff, and beyond toward the valley of the Little Colorado River. Today, this belt of volcanoes extends about 50 miles from west to east.
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Hazards Summary for San Francisco Volcanic Field

Although there has been no eruption for nearly 1,000 years, it is likely that eruptions will occur again in the San Francisco Volcanic Field.
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Hazards Summary for San Francisco Volcanic Field

Although there has been no eruption for nearly 1,000 years, it is likely that eruptions will occur again in the San Francisco Volcanic Field.
Learn More

Sunset Crater

Sunset Crater, located about 25 km (15 mi) northeast of Flagstaff, Arizona, is one of the youngest scoria cones in the contiguous United States and is the youngest of about 600 such cones in the San Francisco Volcanic Field.
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Sunset Crater

Sunset Crater, located about 25 km (15 mi) northeast of Flagstaff, Arizona, is one of the youngest scoria cones in the contiguous United States and is the youngest of about 600 such cones in the San Francisco Volcanic Field.
Learn More
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