San Francisco Volcanic Field
Volcanic field in United States
Key Facts
Elevation
3,850 m (12,631 ft)
Type
Volcanic field
Location
35.347°, -111.678°
Region
Basin and Range Volcanic Province
Rock Type
Basalt / Picro-Basalt
Tectonic Setting
Rift zone
Location
Loading map...
Overview
The vast San Francisco Volcanic Field in northern Arizona has more than 550 vents, the youngest of which is Sunset Crater, named for its brilliantly colored scoria deposits on the cone. The eruptions forming the 340-m-high Sunset Crater cinder cone were initially considered from tree-ring dating to have begun between the growing seasons of 1064-1065 CE; however, more recent paleomagnetic evidence places the activity between about 1080 and 1150 CE. The largest vent, Sunset Crater itself, was the source of the Bonito and Kana-a lava flows that extended about 2.
5 km NW and 9. 6 km NE, respectively. Additional vents along a 10-km-long fissure extending SE produced small spatter ramparts and a 6.
4-km-long lava flow to the east. Ash and lapilli covered an area of more than 2,100 km2 and forced the abandonment of settlements of the indigenous Sinagua Indians.
Volcanic Hazards & Risk Assessment
Primary Hazards
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 | 951 years ago | Historical | Historically active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in North America Volcanic Regions
Quick Info
- •Smithsonian ID: 329020
- •Evidence: Eruption Dated
- •Epoch: Holocene
About the Photo
Snow-mantled Sunset Crater (left-center), seen from O'Leary Peak to the NW, is the youngest volcanic feature of the San Francisco Mountain volcanic field, which covers a vast area of northern Arizona between Flagstaff and the Grand Canyon. The Sunset Crater eruption began about 1100 CE from a chain of cinder cones and vents trending NW-SE, the largest of which is Sunset Crater. Three lava flows were erupted, the longest of which traveled 11 km to the NE.
Photo by Ed Wolfe, 1973 (U.S. Geological Survey).
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.