As scientist in charge, Mike Poland hears a lot of erroneous notions about Yellowstone’s volcanic system. Here are some FAMs — frequently addressed misconceptions:
Is Yellowstone overdue to erupt?
No, Poland said. He’s heard claims that Yellowstone erupts every 600,000 years on average. The last major eruption was 631,000 years ago; the two previous eruptions were 2.1 million and 1.3 million years ago, so the average period between them is about 730,000 years. But even that number is based on limited data, and so “is basically useless,” the geophysicist said. And, volcanoes don’t accumulate magma at a regular rate, so they don’t erupt on a regular schedule.
Will the next Yellowstone eruption be an Armageddon-level blast?
Not all eruptions are Armageddon, Poland said. The most common form at Yellowstone is a lava flow, and they happen only once every few tens of thousands of years. There have been more than 20 lava flows since the last big explosive eruption 631,000 years ago.
Can a seismic event on the West Coast trigger an eruption at Yellowstone?
No. A lot people think all volcanoes are connected, Poland said. They think that the next big Cascadia quake will set Yellowstone off, or vice versa. But volcanoes don’t work that way, he said.
Are we seeing more volcano activity now?
No. Volcanoes aren’t any more active now than at any other period of time, Poland said. People tend to have a bias for the significance of recent events, Poland said, and volcanic activity in Hawaii, Iceland and St. Vincent in the Caribbean have been getting a lot of attention.