(Editor's Note: This year Yellowstone National Park celebrates its 150th Birthday. In honor of that historic milestone we're bringing you a new series called "Yellowstone Revealed." These reports will offer a glimpse into the park's colorful history and stories that you've likely never heard before. The fifth report - "Deadly Volcano" - tells the story of the Supervolcano that lurks under the surface of the world's first National Park.)
YELLOWSTONE NATIONAL PARK - Yellowstone is home to an active Supervolcano. When it last erupted more than 600,000 years ago, it was thousands of times larger than the eruption of Mount St. Helens.
Yellowstone was created as the world’s first national park in 1872 because Congress was impressed with its amazing thermal features. Indeed, The park has the largest concentration of thermals in the world, and people come from all over the world to see them.
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The geysers, fumaroles, and hot springs are part of one of the world’s largest active Supervolcano.
Dr. Robert Smith is considered a leading expert on Yellowstone’s Supervolcano. He started studying the park’s geology in the 1950s. He is the only person to photograph Steamboat, the world's tallest geyser, as it erupted from the air on July 6, 1984.
Smith said his plane was running out of fuel and he was about to return to West Yellowstone when he took the picture of the eruption.
“And it’s a very spectacular picture because it shows the water height, about 500 feet, and then the steam height, about another 500 feet, and there was a mist cloud about another 500 feet above that,” Smith said.
In 2014, Smith’s studies revealed the magma pool beneath the Supervolcano was much larger than previously thought.
“Before we thought it was 20 kilometers long," Smith said in 2014. "We discovered just this year that it’s two and a half times bigger. Two point five times. It’s 90 kilometers long.”
People were concerned it meant the Supervolcano might erupt again, sooner than previously thought. In numerous interviews, Smith said reassured them that was not the case.
“The probability of a large, giant eruption is point zero, zero, zero one four percent per year,” he said.
So dying from the big one is not likely anytime soon. But Smith pointed out that Yellowstone area geologic features can kill.
The deadliest threat is from earthquakes.
Said Smith: “1959 the Hebgen Lake Earthquake ruptured only a fault that was 40 kilometers long. It killed 28 people. But these things dominate the hazard. They are 95% of the total risks of Yellowstone.”