Nice pictures Eric, thanks for sharing. I agree, the last 2 pics are pre-May 18th eruption. They look similar to some pics I got from DNR Geology folks in 1980.
Thanks for sharing the pictures. I was on my way home after just climbing Rainier when Saint Helen's erupted again. Have a couple of photos I took after seeing it billow up in the rear view mirror. Was glad I was off the mountain at the time she went off.......
Eric, thanks for posting these pictures of a spectacular event. Although there was a magmatic eruption on June 12 but not June 22, the pictures are from the July 22, 1980 eruption...except the last two.
Eric Willhite wrote:
=pre-eruption?
The last two were taken after a non- magmatic eruption that occurred shortly after the initial phreatic ( steam blast) activity. The initial phreatic event was on March 27, 1980 and the phreatic event that covered the southeast and east aspects of MSH with a light coating of ash occurred on March 30.
None of the first nearly two months of activity involved the ejection of any new, primary volcanic material until the famous May 18th Plinian eruption that decapitated the mountain. In other words all that occurred between March 27 until 8:32 a.m. on May 18th was the mountain more or less " clearing its throat" as rock was blasted out by powerful explosions of pressurized steam.
The dark stuff on the snow in the last two pictures is lithic ash , composed of pulverized rock fragments. In the March 30 event there were strong NW winds that carried ash at least as far as Pendleton.
The ash from May 18 was vitric ash, - at least after the initial lateral blast - composed of new magmatic material. In the images Eric posted from the July 22, 1980 eruption, part of what happened is the lava dome that began forming on June 12 was being blasted apart, only to reform and be blasted apart half a dozen times until by the end of 1980 the first dome complex was well established.
I say " first" because a second even larger dome compkex formed in the crater next to the first from 2004 until 2008.
Too much information, so I'll stop now........
Passing rocks and trees like they were standing still
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Passing rocks and trees like they were standing still
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