Thursday, April 27, 2017

Mt. St. Helens

Karin and I were camped at the Mt. St. Helens visitor center, and about 6 pm, Karin got the wild hair idea that we should drive up the mountain to watch the sunset, and try to get some pictures with the Alpen Glow on Mt. St. Helens.  Realize that the world scale is quite a bit different out there.  From the visitor center up is about 40 miles of mountain driving.  So, we made some sandwiches from SafeWay Spice Baked Pork, mugs of hot chocolate, and took off.

On the way up, we saw a few elk who were camera shy.

We finally got up to the overlook, and saw the evening sun shining on the mountain, but this dadgem cloud was on top of the mountain.  It would be a race to see if the cloud left first, or the sun set first.  The mountain is about 10-13 miles away from this vantage point.

You can see the rain falling in the valley to the left of the mountain.  You might not have been alive, but Mt. St. Helens erupted May 18, 1980.  I can't really tell this story as well as the USGS, so I'll just give you a link to the USGS explanation about Mt. St. Helens.  It's worth your time to learn about it.  Nowadays, its just 8,3,66 feet high, but before the eruption it was 9,677 feet high.  So, about a quarter mile of mountain slide off in the landslide and explosion.

Meanwhile, off to the west and near to Seattle is Mt. Rainier.  As I said, scale is wicked hard to judge.  From where I took this picture, Rainier is about 100 miles away.  It is 14,411 feet high.

As we waited on the cloud to move or the sun to set, Sophie chased her tail

Meanwhile, you can look down into the Toutle River Valley.  In some places here, the sediment from the St. Helens landslide is as deep as 600 feet.  A lot of that is the 1/4 mile of mountain top that blew and slide off.  That's the Toutle River.

If you take my water resources class, I usually cover sediment transport on this river, and the huge sediment retention lake and dam downstream.  Here, you can see the river cutting through the sediment, slowly eroding it.  I guess the banks you see by the river are about 75-100 feet high.

Meanwhile, it looked like that rain would come towards us, but it just went out into the middle of the valley.  Mt. Rainier on the left side, again..  The edge of Mt. St. Helens on the right.

Here's a pre-1980 picture from the visitor center.  By all accounts, it was a beautiful, picturesque example of a volcano cone.

As is this one from after the eruption.  I have a lot of these that I took myself that I use in my classes, but not with me on this trip. And we couldn't take new pictures because, this being winter, the road to the upper observatory - Joihnson Ridge Observatory - was still closed.

Well, the cloud won and the sun set before the cloud blew off the mountain, though it did move up the flanks a bit, so you could see a lot of the mountain and the snow.  You win some, you lose some.  Here though, those SafeWay Spiced Pork Sandwiches did a number on me.  It was a long, dark trip back down the mountain.

I took pictures of the pictures at the visitor's center.  This is Spirit Lake, which got filled in and no longer exists.

Here's the sequence taken by Joseph Rosenbaum, the only actual pictures of the landslide and blast.

Through the magic of computers, you can watch this animated on a youtube  video here.  I think this version is from a Discovery Channel Documentary.

Take home lesson:  You think big geologic events are a thing that happened "back then," but they're not.  They are just spaced out in a time scale that makes sense in a big geologic way.  This is a theme that you'll see in a future blog about the Missoula Flood.

1 comment:

  1. I climbed, scrambled, walked to the top of Mt. St Helens back in August of 1987. I will have to find my film pics and post them some day.