Mt. St. Helens

[OperaTenor]

She blew off a little steam and ash today. So what of it?
From what I've read, it sounds as though the media is speculating about subterranian "magma flow", as if the mountain may start spewing great gouts of red-hot lava.
It doesn't happen that way from that type of volcano.
Mt. St. Helens, as well as the other peaks in the Cascade chain, are sitting on top of what are called pyroclastic flows. It is lava that's not quite as hot as you see on all of the documentaries. It doesn't glow red, and doesn't flow like water. It moves very slowly, and a significantly greater amount of pressure is required to get it to move, let alone erupt. That was why the 1980 eruption was so devastating.

My opinion: MSH is rebuilding. The 1980 eruption blew ~half of the mountain away. I'll bet we see periodic small eruptions like today's for the next 120 years or so(if we manage to not wipe ourselves off the face of the Earth before then), until it looks more or less like a graceful, snow-capped Cascade peak, then will blow its top once again.

[OperaTenor]

I just read there was another steam blast today, and that government scientists have raised the alert level to 3, which means they feel an eruption is iminent in the next 24 hours.

Anyone else find this fascinating?

Beats the heck out of the Presidential race, IMO.

[dai bread]

Living as I do on a volcanic field which we all hope is extinct and not just dormant, I find anything tho do with volcanoes fascinating. Mt. St.Helens seems to have erupted from the side in the picture published in my newspaper. I must check the Web.

[Selma in Sandy Eggo]

Just checked the volcano watch on Helen. It blew a big steam cloud today, from several vents, and the steam contained a "significant" amount of ash.

The USGS page has a plot of the recent rmblings, and they've been decreasing in depth, increasing in frequency, and increasing in intensity. That plus the steam sounds like that mountain may just go all drama queen on us again.

Last time, it messed up the paint on my sister's car, in Denver. It seems that volcanic ash is acidic and if it settles on a moist painted surface it can etch it.

Last time, Helen blew out one side of the cone, there was a HUGE pyroclastic flow down the side of the mountain and across Spirit lake, and there are still trees blown flat where the ash flow blew them over. The park website says it's a "stratovolcano" which means it's built of alternating ash and lava flow layers, so I guess it's done this ash business many times before.

Keep watching it, dai, it's bound to do something exciting sooner or later. At least, that's how my reasoning goes.

[OperaTenor]

I think it's rebuilding itself right now. My bet is it will continue erupting, and there will be a fairly impressive blast at one point, but it will result in a bigger lava dome, and not take off the top of the mountain as in 1980.

I took Historical Geology in college in Eugene, OR, in the spring of 1980. We spent every other class just talking about MSH. It was extremely fascinating.

Basalt has never looked the same since. <geological humor smilie>

[barfle]

Instead of watching CDJs, you can watch the mountain here.

[OperaTenor]

Hi Barfle,

V. cool. I've bookmarked it.

Thanks!

[barfle]

Soitnly!

(yeah, I'm postwhoring)

[Selma in Sandy Eggo]

And the latest:
---------------------------

MOUNT ST. HELENS, Wash. -- Part of Mount St. Helens' crater floor has risen 50 to 100 feet since Tuesday while earthquake rates have been low, signs that magma is moving upward without much resistance, scientists said Thursday.

"The skids are greased," Jake Lowenstern, a U.S. Geological Survey volcanologist, said at a news conference at the Cascades Volcano Observatory in Vancouver, Wash.

With the latest rising, an area of the crater floor just south of the nearly 1,000-foot lava dome has risen about 250 feet since the mountain began stirring two weeks ago, Lowenstern said.

There's no way to tell when magma might reach the surface, he said.

-----------------------------

Yup. Drama to follow.

[treebeau]

Nice picture on the web cam, but kinda boring.

Regards,
Tim B.

[dai bread]

Yes indeed. Nice webcam pics. Shall leave the computer running for a while & download a movie I think. 3.5mb will take a while to download.