Volcano Eruptions

A swarm of earthquakes is one sign that an eruption may be brewing and last winter Yellowstone National Park was rocked by a rash of tremors.

"There were over a thousand earthquakes in about one week," said Park Geologist Hank Heasler. "That isn't unprecedented in the parks history, but it is unusual."

"It was one of the largest swarms in the past 20 years," said USGS Volcanologist Dr. Jake Lowenstern. "It certainly got a lot of people's attention, including ours."

The entire park that exists today is the caldera of the last major eruption 240,000 years ago and experts say that eruption was destructive on a scale like we have never seen before.

"This put out about a thousand times more volcanic material than Mount St. Helens," said Heasler. "To put that in perspective, it's the difference between spending $1,000 and $1,000,000.

That eruption in 1980 in Washington was the deadliest and most destructive volcanic event in the nation's history. 57 people lost their lives in the eruption and volcanic ash was scattered across 12 surrounding states. But experts say another major eruption at Yellowstone would be much more deadly and destructive.

But how will we know if another big eruption is brewing? Dr. Jake Lowenstern is a member of the Yellowstone Volcano Observatory which is in charge of monitoring the park's supervolcano. The partnership between Yellowstone National Park, the US Geological Survey, and the University of Utah uses seismograph and ground deformation sensors to keep an eye on what is happening deep underground. Based on their research of the Yellowstone hotspot, the Observatory says another eruption is likely and may even happen in our lifetime. But fortunately for tourists and those living nearby, they say it won't be the big one.

"In a worse case scenario, the big super eruption, is very destructive and would cause a world of hurt to anybody living in the region around Yellowstone and surrounding states," said Lowenstern. "However, the big eruption is not what's most likely to happen here if we do get a volcanic eruption. Much more likely is some localized lava flows that will have an affect within the park. People will need to move out of the way. There will be fires. But people living hundreds of miles away, or even tens of miles outside the park are very unlikely to be affected."

"We have a very sophisticated monitoring system that will give us advanced warning if anything does start to occur," said Heasler. "So the best thing to do is come to the park and enjoy the beauty."