On May 18th, 1980, thirty years ago today, at 8:32 a.m., the ground shook beneath Mount St. Helens in Washington state as a magnitude 5.1 earthquake struck, setting off one of the largest landslides in recorded history - the entire north slope of the volcano slid away. As the land moved, it exposed the superheated core of the volcano setting off gigantic explosions and eruptions of steam, ash and rock debris. The blast was heard hundreds of miles away, the pressure wave flattened entire forests, the heat melted glaciers and set off destructive mudflows, and 57 people lost their lives. A photo-essay.
posted by Nothing... and like it on May 18, 2010 - 76 comments

A supervolcano may be brewing beneath Mount St Helens
posted by Artw on Jun 10, 2009 - 86 comments

Mount St. Helens Erupting.
Anybody have any money riding on this?
posted by Parannoyed on Oct 1, 2004 - 11 comments

Can we predict volcanic eruptions? PBS aired a NOVA program called "Deadly Shadow of Vesuvius" in 1998 which suggests that we can by monitoring small scale earthquakes which "swarm" as an eruption approaches. Why is this important now? Look at this map, which indicates the occurence of over 40 earthquakes under Mount St. Helens just today, with 10 being over 3.0 on the Richter scale. The Pacific Northwest Seismograph Network has issued a series of alerts with more detail. National Geographic is reporting that an eruption is imminent.
posted by monju_bosatsu on Sep 30, 2004 - 19 comments