Taxonomy term

pyroclastic flow

Pyroclastic flows, not caldera collapse, caused Santorini tsunamis

The 1650 B.C. eruption of the Greek island volcano Santorini, located in the Aegean Sea, triggered tsunamis that heavily damaged coastal towns and disrupted vital shipping and trade operations, events thought to be important factors in the demise of the ancient Minoan culture.

17 Mar 2017

Slow-moving super-eruptions still travel great distances

When Hollywood movies depict the destruction unleashed by volcanic eruptions, they usually focus on red-hot lava, but even more dangerous are pyroclastic flows: mixtures of rocky debris and searing hot ash and gas that move as fast as 700 kilometers per hour and can bulldoze, incinerate and suffocate anything in their paths. In a new study looking at pyroclastic flow deposits associated with the Silver Creek Caldera in the southwestern U.S., researchers have found that not all pyroclastic flows are so swift. Dense, slow-moving flows can still wreak havoc over vast distances.

29 Jun 2016

Hazardous Living: Thirty years after Mount St. Helens exploded

Thirty years ago today, sometime not long after 8:30 a.m. Pacific time, Mount St. Helens explosively erupted. The shock wave from the eruption washed over Oregon and Washington, shaking the ground up to 400 kilometers away. Two earthquakes followed, at 8:32 and 8:34 a.m. Shortly thereafter, with a tremendous burst, the upper north flank gave way as gas, steam and ash vented outward and sent out an immense landslide of hot rock, mud, water, ash and debris.

18 May 2010