• Source: Crooked River caldera

The Crooked River caldera is a large and ancient volcano that straddles three central Oregon counties. The diameter of the caldera is about 41 by 27 kilometres (25 mi × 17 mi) and is notable for the welded tuff present at Gray Butte, Smith Rock, Powell Buttes, Grizzly Mountain and Barnes Butte. The volcano is considered extinct and last erupted about 29.5 Ma.




References

Kata Kunci Pencarian:

• Crooked River caldera
• Deschutes County, Oregon
• Barnes Butte
• Grizzly Mountain (Oregon)
• Gray Butte
• Prineville, Oregon
• Smith Rock State Park
• Powell Buttes
• Columbia River Basalt Group
• List of volcanoes in the United States