A new study explains why even gas-rich, supposedly explosive volcanoes sometimes erupt quietly instead of blowing apart.

It was a quiet Sunday morning, at 8:32 a.m., 38 years ago when Mount St. Helens blew its top, sending tons of ash into the sky. The volcano had been quiet since the 1850s, but in 1980, geologists were ...

May 18 marks the 45th anniversary of the catastrophic eruption of Mount St. Helens in southwestern Washington. The blast in 1980 killed dozens of people and reshaped the volcanic peak in the Cascade ...

Learn how stress inside a volcano can make gas bubbles form early, helping explain why some eruptions stay quiet instead of ...

Sunday, May 18 marks 45 years since the disastrous eruption of Mount St. Helens. Fifty-seven people were killed and it remains the deadliest volcanic eruption in U.S. history. At 8:32 a.m. on May 18, ...

The explosiveness of a volcanic eruption depends on how many gas bubbles form in the magma—and when. Until now, it was ...

Scientists have uncovered a long-missing piece of the volcanic puzzle: rising magma doesn’t just form explosive gas bubbles ...