Book 12, Question 87
Why Is Yellowstone Called a Supervolcano System?
Yellowstone is called a supervolcano system because it sits on a giant bowl-shaped caldera! A caldera is a huge hole made when the ground collapses after a giant eruption. Yellowstone's last giant eruption was about 640,000 years ago.
More fun facts
- Yellowstone's caldera was made by a huge eruption about 631,000 years ago.
- That was the third of Yellowstone's massive eruptions.
- The caldera is about 48 by 72 kilometers (30 by 45 miles) wide.
- Since then, about 80 smaller, non explosive eruptions have happened, mostly lava flows.
- The most recent eruption at Yellowstone was a lava flow 70,000 years ago.
- Small quakes, ground rising and sinking, and gas releases are normal there and do not mean an eruption is coming.
Sources: National Park Service, U.S. Geological Survey, U.S. Geological Survey
Questions kids ask
Is Yellowstone overdue to erupt?
No. Volcanoes do not erupt on a schedule, and scientists say Yellowstone is not overdue.