Some of Arizona’s Spectacular Peaks Are Actually Active Volcanoes!

Quick, what land features come to mind when you think of the Arizona landscape? Canyons? Plateaus? Mountains?

Volcanoes?

If volcanoes didn't make your list, no one would blame you. Even geologists are perplexed about finding volcanoes in Arizona - much less active volcanoes.

Exploring Arizona’s Volcanoes and Why It's Weird They Exist Here

Arizona is hiding a fascinating secret in plain sight: active volcanic fields. Our state is home to more than 600 volcanoes dispersed over 1,800 square miles.

READ MORE: Discover the Amazing Biodiversity of Arizona’s Sky Islands

According to scientists, Arizona’s volcanoes shouldn't exist. Arizona sits on the North American Plate, unlike the Pacific Ring of Fire, where tectonic plates collide.

From a geological standpoint, active volcanoes in Arizona don't make any sense. Volcanoes usually form at tectonic plate boundaries, where "two tectonic plates meet and move relative to each other," like those found along the San Andreas fault on the Pacific Coast.

READ: Recreational Shooters in AZ May Not Like this New BLM Proposal

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Nearly all of Arizona's volcanoes are cinder cones. Wikipedia explains that a volcanic cinder cone "is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent."

Essentially, they look like big mountains with a bowl sitting at the top.

Where Are Arizona's Volcanoes?

Here's where you'll find some of Arizona's volcanoes:

1. San Francisco Volcanic Field
   • Located near Flagstaff, this vast volcanic field boasts over 600 volcanic features. The San Francisco Peaks are the most impressive volcanoes in the state. The peaks are 5,000 feet above the plateau, and they were once fiery giants, erupting lava and ash.
   • The last time the San Francisco volcano erupted was around 1100 AD, with Sunset Crater blowing its firey top.
2. Uinkaret Volcanic Field
   • Nestled at the north rim of the Grand Canyon, Uinkaret has a unique claim to fame: its lava flows cascaded into the canyon, creating temporary lava dams over 650 feet high.
   • Geologically speaking, this volcano didn't erupt all that long ago. Experts think it may have been as recently as 1,000 years ago.
3. Pinacate Volcanic Field
   • Straddling the Arizona-Mexico border, Pinacate’s rugged landscape conceals ancient volcanic craters and lava flows.
   • The last eruption was a millennia ago, but evidence of the lava flow creates an eerie beauty in the landscape.

Are Arizona's Volcanoes in Danger of Erupting?

So why are the volcanoes here in Arizona? Scientists say there's a hotspot under the crust below Arizona. A theory suggests that volcanoes are formed because of geologic conditions called hot spot volcanism.

Hot spot volcanism is unique because it does not occur at the boundaries of Earth’s tectonic plates (as we mentioned earlier with the San Andreas Fault), where all other volcanoes are found. Instead, you'll find these volcanoes at abnormally hot centers known as mantle plumes.

READ: Scary Mountain Lion Attack in Arizona County

Arizona doesn't have any erupting volcanoes right now. However, the San Francisco Volcanic Field and the Uinkaret and Pinacate Fields are considered active because they could erupt in the future.

YouTube user Aidan Robbins explains how Arizona's volcanoes were formed and why it's really weird they exist in our state:

Sources:

1. VolcanoDiscovery
2. The Geography Teacher
3. AZGS
4. AZGS - Volcanic Rocks
5. LolaApp
6. Khan Academy
7. YouTube/User: AidinRobbins
8. Wikipedia: cinder cones
9. National Geographic