Yellowstone’s Massive Hydrothermal Explosion Reminds Us That It’s an ‘Box of Bombs’ Visited by 4 Million People Each Year

Tuesday, July 23. 10:19 a.m. (local time). A group of tourists is walking through the Biscuit Basin, an area of geysers and thermal pools in Yellowstone National Park. Suddenly, a massive eruption of steam, water, rocks, and dirt surprises everyone.

No one was injured, but the images captured by the same tourists as they fled the scene are mind-boggling.

The damage is also significant. Many of these areas of Yellowstone have elevated wooden paths that allow tourists easy access to the most exciting places. However, the rain of debris that followed the explosion destroyed the structures.

As the situation continues to unfold, the entire area of the park is closed to visitors.

What happened? As Associated Press reports, Mike Poland, a scientist at the Yellowstone Volcano Observatory, said the explosion “could have resulted from a clogged passageway in the extensive natural plumbing network that underlies Yellowstone’s world-famous geysers, hot springs, and other thermal features.”

This type of clog can quickly cause a buildup of heat and pressure, leading to a massive explosion. However, it’s not the most enormous explosion seen in the park.

Bigger explosions? According to Poland, the largest known crater created by a hydrothermal explosion on Earth is 1.5 miles across and is in Yellowstone. As the experts from the U.S. Geological Survey told CNN, “Large hydrothermal explosions occur on average every 700 years.”

The heart of Yellowstone is a volcanic caldera, which measures 43 by 28 miles. In this case, we’re talking about much smaller explosions. The Biscuit Basin experienced such blasts in 1959, 2009, and 1991.

We underestimated the park for too long. “What we saw today was spectacular and definitely hazardous. But on the scale of what the Yellowstone system has done in the past, it was relatively small. It’s a very good reminder of an underappreciated hazard in Yellowstone,” Poland explained.

Indeed, the fatality rate in the park isn’t remarkably high (about only 22 people have died from this type of explosion since 1890). Still, we’re talking about a place with more than 4 million visitors annually. And whose risks we cannot predict.

This article was written by Javier Jiménez and originally published in Spanish on Xataka.

Imagen | USGS | Yellowstone National Park

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