March 8, 2005 U.S. Department of the Interior U.S. Geological Survey The Ongoing, Mind-blowing Eruption of Mount St. Helens Dan Dzurisin On behalf of colleagues at the USGS Cascades Volcano Observatory Geological Society of the Oregon Country (GSOC) meeting Portland State University November 17, 2006

whaleback Let’s skip right to the good stuff lava dome Feb. 22, 2005 East arm, Crater Glacier West arm, Crater Glacier If this doesn’t quicken your pulse, check that you have one

It started on a quiet September morning… September 23, 2004 SEP webicorder (on lava dome) …with an earthquake swarm… September 24, 2004 …that didn’t stop!

09/24 09/25 09/26 09/27 09/28 09/29 09/30 PDT Within a few days, several earthquakes were occurring per minute…

September 29, 2004 …and a large welt was rising on the south crater floor. Eight days after the first earthquakes…

By October 1… October 1, 2004 Mount St. Helens’ first eruption of the 21st century was underway!

Seismic Amplitude, September 20, 2004 – January 5, 2005 Notice of volcanic unrest (9/26) USGS and PNSN provided timely information and hazards assessments to partner agencies and the public Tremor Steam and Ash Volcano advisory (9/29) Tremor Steam and Ash Volcano alert (10/2) Volcano advisory (10/6) On October 11, 2004, the first new lava emerged and the dome-building phase of the eruption was underway

The eruption sparked intense interest from the media and public

USGS scientists provided daily press briefings at CVO until a joint information center was set up at USFS Gifford Pinchot National Forest Headquarters CVO kept its attention focused on the volcano…

October 7, 2004 The welt grew at a prodigious rate (That’s a BIG helicopter) Until, on October 11… 2004 welt dome

October 11, 2004 …a hot (775°C, 1430°F) lava spine emerged

November 4 In late October, a whaleback-shaped extrusion appeared

A time-lapse camera on Sugar Bowl Dome records the whaleback’s growth (sometimes)

Scientists are using a combination of time-tested and innovative techniques to study the eruption Helicopter mounted FLIR and video module

“Spider” – helicopter-slingable volcano-monitoring station

There are several species of spider……and they’re evolving! MARV Lander - Brain child of Marvin Couchman, USGS/CVO Marvin

We’ve placed spiders on the dome… …and on the new dome… …including some places even a volcanologist wouldn’t go “Whale rider” spider In the process, we’re learning a lot about …

February 22, 2005 Eruption mechanics dome Volcano-glacier interactions Dome-building processes and hazards “Fault gouge” is dome rock pulverized by earthquakes “Bathtub rings” record dome growth Why bother? (So what?)

Volcano Studies: Challenges and Opportunities for the 21 st Century Radar-interferometry satellites can monitor most of the world’s volcanoes at centimeter-scale accuracy with high spatial resolution and virtually complete areal coverage Networks of continuous sensors, including seismometers, GPS, strainmeters, and tiltmeters, can maintain constant vigilance even at long-dormant volcanoes. In the United States, EarthScope (USArray, PBO, SAFOD, InSAR?) is the most ambitious and promising Geoscience initiative ever undertaken. Autonomous, self-organizing sensor networks can provide essential real-time information that is spatially and temporally dense in areas otherwise inaccessible for reasons of logistics or safety. Such networks can trigger event-driven data acquisitions by Earth- observing satellites, thus supporting continuous global surveillance of hundreds of dangerous volcanoes. USGS/CVO, WSUV, and NASA are developing a prototype system for deployment at Mount St. Helens. By monitoring volcanoes more thoroughly using a combination of old- school and 21 st century techniques, scientists might be able to anticipate the onset of shallow volcanic unrest, intensify monitoring, and provide longer term warnings of impending eruptions.

Something EXTRAORDINARY is happening at Mount St. Helens. The volcano’s last 2 quiescent periods lasted 123 years ( ) and 18 years ( ). Past inter-eruption periods have lasted for several millennia. We’re living in interesting times.

This is not THE END!