Mount St. Helens

http://www.fs.usda.gov/mountsthelens

This is by far the most astonishing thing I have seen yet. The top of the mountain blew off on May 18, 1980. It went from 9,677 feet to 8,365 feet tall in 9 hours.

Here is the mountain before the volcano.




and here it is after...

I can't get the spacing right on the typing.

That is just astounding to me.

The volcano started "activity" in March of 1980. There were earthquakes almost every minute. And steam coming from the top of the mountain. There was a "bulge" building on the north side, growing as much as FIVE FEET every day! Then, the steam and the earthquakes stopped. This was 1980, and there was not all the science and/or equipment that there is today. They evacuated the area anyway, but for only five miles.

Apparently, the frozen snow and ice, mixing with the hot lava sealed the volcano closed. But, the pressure was still building, unbeknownst to the scientist. The mountain did not go back to sleep.

The morning of May 18, 1980, the bulge collapsed, shooting volcanic fire, gases, ash, etc, LATERALLY. The first blast went sideways! This, of course, opened the top, relieving the pressure, and for the next nine hours, the volcano was shooting out of the top.

I can't remember all of the facts, i.e. how far the blast went, how many miles of devastation it caused, etc. I do remember they said the ashes took two weeks, but they did circle the globe. Also I remember, they said sound waves bounce, so no one in Portland, OR heard the blast, but it was heard in Eugene, OR which is farther south. And the Toutle River, now runs gray.

The government declared the area a national monument, and has not "replanted". They want the area to recover naturally, and it is doing so, slowly but surely. They are only doing that with the surrounding area (the observation point was five mile from the mountain) but they did replant trees in the outer area. It took 6 years to clear the debris and re-plant.

The mountain is re-growing itself, from the inside out. Thirty years later and this is what it looks like.

There is a lava dome building in the middle. The mountain is RE-GROWING itself! There is a glacier building behind the lava dome. Sounds like another volcano just waiting to happen. They think one has, and will happen every 100 years. (I should be out of the area by then.)

I stopped at the Visitor's Center that is about five miles after the mountain turnoff. One of rangers gave a talk (once again, free). I have to give props to these rangers. They are mostly young, obviously love science and nature, and some of the  most enthusiastic people I have come across. I listened to another "ranger talk" at the closest observation point, Johnson Ridge Observatory.
http://vulcan.wr.usgs.gov/Volcanoes/MSH/NatMonument/PointsInterest/johnston_ridge.html

I know it sounds "cheesy" to listen to a "ranger talk", but they really are worth taking the time.

The mountain blew it's top off, and now it is re-growing! Mother Nature is something else, indeed.