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An explosion at Yellowstone National Park

A hydrothermal explosion at Yellowstone National Park surprised visitors and caused them to run for safety as steam, rock, and dirt shot into the sky.

The explosion was possibly due to minerals clogging an underground pipe. No injuries were reported, but the explosion damaged a boardwalk in the Biscuit Basin Area. Videos of the event show water and debris raining down over the park. Hydrothermal explosions are somewhat common in Yellowstone. They occur when underground water turns to steam. Similar eruptions happened in the Biscuit Basin in 1959, 1991, and 2009. Predicting these events is difficult as they can happen instantaneously. The Park Service will investigate if the explosion altered the underground system by measuring the chemical makeup and temperature of nearby geysers and vents. Despite the explosion, no changes in the volcanic system have been detected, and the park remains at normal activity levels.

http://www.newsinlevels.com/products/an-explosion-at-yellowstone-nationalpark- level-3/.