Monday, March 23, 2015

35th Year Anniversary of Mount Saint Helens' 1980 Eruption
Let's Get Ready to RUMBLE!
35th Year Anniversary of Mount Saint Helens' 1980 Eruption
May 18, 2015
-- Coming Soon --
(to a volcano near you)

Cascades Volcano Observatory (CVO)
 [MSH Webcam]
updated 2015-03-19
USGS-CVO Open House
When: Saturday, May 2, 2015
1300 SE Cardinal Ct Bldg 10 Suite 100 Vancouver, WA (map)
In commemoration of the 35th anniversary of the May 18th eruption of Mount St. Helens, the
U.S. Geological Survey – Cascades Volcano Observatory
is having an
Open House on Saturday, 
May 2, 2015, from 10 a.m. until 5 p.m.
The Open House will focus on the importance of the 1980 events and
will show the progress made in volcano science, hazard assessment, monitoring methods, and
 eruptive forecasting since that time.
We look forward to sharing our work with the public 
through informational talks, hands-on activities and equipment demonstrations.
U.S. Geological Survey – Cascades Volcano Observatory
Daily Updates available
March 18, 2015
Hello Mount St. Helens Volcano Watchers,

Over the next eight and a half weeks, the USGS Volcanoes Facebook page will feature a daily post of events transpiring 35-years ago, leading to the May 18, 1980 eruption of Mount St. Helens.

The posts will begin on March 19, 2015 with a preview of things to come:  

Imagine, 35 years ago. Mount St. Helens was just a part of the scenic landscape of southwest Washington. A place to hike, climb, camp.  You could stay in one of the lodges at Spirit Lake, rent a boat, fish, maybe even have your own vacation cabin; the kids could go to one of the summer camps on the north shore. Loggers worked the slopes and nearby foothills, the Forest Service kept up campgrounds.  All this was about to change. Tomorrow.

The 1980 activity of Mount St. Helens began on March 20 with an intensifying swarm of earthquakes.The first steam-blast eruption occurred a week later, with high levels of seismic activity, formation of a summit crater, and deformation of the north flank of the volcano. This continued, up to the climactic eruption on the morning of May 18.  Over the next eight+ weeks, follow the USGS scientists as the events unfolded in 1980, with daily posts about recent activity, pictures and video.  What would you have done, had you been there?

The post for March 20:

Mar 20, 1980. At the University of Washington seismology laboratory in Seattle, the pen scratched left, then right, each stroke swinging wider on the drum. There’s been an earthquake, fairly large, maybe at Mount St. Helens. There’s only one seismic station at Mount St. Helens (SHW) so it isn’t easy to verify. After additional analysis, the scientists conclude the earthquake struck just before 3:48 pm, a magnitude 4.2, the strongest in this part of the Cascade Range in 16 years. It is very shallow, plotting only a mile deep beneath the north brow of Mount St. Helens.  Seismologists had noticed small earthquakes in the area from March 15–March 20. Are these tectonic quakes—the little pops and pings of the North American plate as it is squeezed, stretched, and torqued? Or is it volcanic in nature?

Each daily post (7 AM PST) will include a picture, graphic or short video (example attached).  Take a look tomorrow.  We hope you share it with your own Facebook users and Tweet about it.

Liz Westby
U.S. Geological Survey
Cascades Volcano Observatory
1300 SE Cardinal Court
Building 10    Suite 100
Vancouver, WA   98683
(360) 993-8979
 updated 2015-03-19

Posted by PSRG FUN BLOG at 3/19/2015 10:44:00 AM