The Uinkaret volcanic field is an area of monogenetic

Monogenetic volcanic field

A monogenetic volcanic field is a volcanic field of small, scattered volcanic vents. These volcanic fields, containing numerous monogenetic volcanoes, are noted for having only one short eruptive event at each volcano, as opposed to regular volcanoes that have several eruptions from the same vent...

 volcano

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

es in northern Arizona

Arizona

Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

, USA, located on the north rim of the Grand Canyon

Grand Canyon

The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, the 15th national park in the United States...

.

Lava flows from the Uinkaret volcanic field that have cascaded down into the Grand Canyon, damming the Colorado River

Colorado River

The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...

, have been used to date the canyon's carving. One of these cascades is today's Lava Falls. Lava Falls Rapid, below Lava Falls on the Colorado River, is "at all water levels, the most severe rapid in Grand Canyon."

The river was dammed by lava flows multiple times from 725,000 to 100,000 years ago. While some believe that these lava dams were stable, lasting up to 20,000 years and forming large reservoirs, others think they failed quickly and catastrophically as massive floods. Lava flows traveled downriver 76 miles (121 km) from river mile

River mile

In the United States, a River mile is a measure of distance in miles along a river from its mouth. River mile numbers begin at zero and increase further upstream. The corresponding metric unit using kilometers is the River kilometer...

 178 to 254.

One lava flow, from Little Springs, south of Pliocene

Pliocene

The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...

 Mount Trumbull

Mount Trumbull Wilderness

The Mount Trumbull Wilderness is a 7,880 acre wilderness area located on the Uinkaret Plateau in the Arizona Strip. It is managed by the Bureau of Land Management....

, has a cosmogenic helium age of 1300 +/- 500 years BP. Pottery sherds dated at between 1050 and 1200 AD were found within the Little Springs lava flow, which occurred about the same time as the Sunset Crater

Sunset Crater

Sunset Crater is a volcanic cinder cone located north of Flagstaff in U.S. State of Arizona. The crater is within the Sunset Crater Volcano National Monument....

 eruption in the San Francisco volcanic field

San Francisco volcanic field

The San Francisco volcanic field is an area of volcanoes in northern Arizona, north of Flagstaff, USA. The field covers 1,800 square miles of the southern boundary of the Colorado Plateau. The field contains 600 volcanoes ranging in age from less than 6 million years old to less than 1,000 years ,...

 on the South Rim.

Notable Vents

Name	Elevation		Location	Last eruption
	meters	feet	Coordinates
Mount Emma	-	-	-	-
Little Springs	-	-	-	1050-1200 AD
Prospect Cone	-	-	-	-
Mount Trumbull	-	-	-	-
Vulcan's Forge	-	-	-	-
Vulcan's Throne Vulcan's Throne Vulcan's Throne is a cinder cone volcano and a prominent landmark on the north rim of the Grand Canyon in Arizona, USA. Vulcan's Throne, about a mile west of Toroweap overlook, is part of the Uinkaret volcanic field....	-	-	-	73,000 years ago

See also

• Geology of the Grand Canyon area
  Geology of the Grand Canyon area
  The geology of the Grand Canyon area exposes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old...
  
  
• List of volcanoes in the United States of America

External links

• Uinkaret Volcanic Field, Western Grand Canyon, Arizona at Volcano World
• Full-size version of image in infobox, NASA ASTER
  Advanced Spaceborne Thermal Emission and Reflection Radiometer
  ASTER is a Japanese sensor which is one of five remote sensory devices on board the Terra satellite launched into Earth orbit by NASA in 1999...
  
  satellite image.