The dominant rock type in the Yellowstone region is rhyolite, and that is very rich in silica. As hot water circulates underground, it can dissolve that silica and bring it to the surface, where it is ...

More geological changes are occurring at Yellowstone National Park, as another hole forms in one of the park's basins.

Get ready for a little Christmas in July: There’s a new baby blue pool in Yellowstone National Park, and science suggests it started forming on the winter holiday.

Scientists are tracking changes at the giant supervolcano that lies under Yellowstone National Park, but they say there's no need to worry at the moment. “The western part of the Yellowstone ...

Yellowstone National Park geologists identified a new thermal feature in Norris Geyser Basin. It may have coincided with a ...

A surprise eruption in Yellowstone National Park shot steam, water and dark-colored rock and dirt an estimated 100 feet into the sky and sent people running for safety.

A surprise eruption in Yellowstone National Park shot steam, water and dark-colored rock and dirt an estimated 100 feet into the sky and sent people running for safety.