Mt St Helens Collapse.mov

This movie shows a physics-based computer simulation of the flank collapse and debris flow from the Mt. St. Helens eruption of May, 1980.
For more natural hazard simulations visit es.ucsc.edu/~ward.

[@wi11y1960]

best annimation I have yet to see of what the debris flow was and where it went. Thankyou

[@SCW1060]

wi11y1960 the very best that I've seen was live TV shots during the St. Helens eruption events here in the Seattle/Tacoma region. It still gives me the chills when I drive down to the Mt. St. Helens observatory and look straight into its creater and still see the debris flows. I will be doing a video on this very soon on my new channel

[@Aryon1969]

wow I had no idea the slide lasted that long and traveled that far truly incredible. Thank you for posting this.

[@jimvick8397]

I was 5 years old when it blew and we were driving from Spokane to the Tri Cities through the ash... It was freaky because the ash got caught up in all the hidden wind features of the landscape... Dust devils looked like giant wedge tornados while winds that blew down valleys looked like giant worm from the movie Dune... There were other bizarre features in the air that only became visible when the fine ash was caught up them. It was truly the things of nightmares. Never seen anything like it since... really don't want to either.

[@ryanboulette9194]

Please l01plyvv666 the top

[@aw8079]

Lewiston Idaho, May 18 midday the sky went dark and it got really warm. Weirdest thing I've ever experienced.

[@dwpalme2670]

Bullshit

[@mudhutproductions]

Fantastic video! I've never seen this much detail so well presented. Thanks!!

[@kpasstenceBETA]

Nice! You should do one showing how Spirit Lake was effected by the landslide. I noticed the lake was not in this simulation, but saw all the slide debris flowing into the lake basin. Makes you think how dramatic and quickly such a large body of water was basically upheaveled. Keep up the awesome work!

[@user-td1uv2nt3r]

I am still hoping to see a recreation of that somewhere, sometime. The thought of that landslide hitting the lake and forcing the water up the hillside over 800ft and then sloshing back into the filled in lakebed carrying all the timber with it. I read that the current bottom of the lake is at a higher elevation than the original lake surface, which is just mind boggling to visualize. The only thing that I've seen that comes close are the signs in the area depicting the original shape of the lake along with the locations of the camps and lodges dotting the original shoreline. Hard to fathom.

[@BenFerraiuolo]

Very good animation! Well done!

[@JoeyHazboun]

congratulations to mt st helens because it erupted in my favorite way . and my favorite part was the largest landslide in recorded history of mt St helens

[@Youngstown529]

I was 10 when this happened. I wondered why they never found Harry Truman, who perished at Spirit Lake. Now it's clear to me why. Within 3 minutes he and everything he loved were scraped off the land and pulverized together under tons of earth and debris. Then the mess sloshed backward. When we think of volcanos, we think of movies where the debris is blown straight up into the sky and rains down like snow. This is very different isn't it?

[@joeguajardo5092]

Excellent

[@ChuckD59]

Maybe a minor point, but I'm pretty sure at 0:57 where it states "a massive explosion...took out the bulge", the reality is the bulge was forced out so far that it couldn't support itself, sloughed off and exposed the fissures that were forcing it out. Like a champagne cork being eased off externally and then popping off and suddenly releasing the pressure. My point is just the mechanical order of the event. Otherwise, nice analysis. Thanks.

[@ssoltau9318]

Well, technically there was an earthquake underneath the mountain which measured 5 on the Richter Scale. It caused the bulge to collapse, which reduced the pressure on the magma beneath it which then exploded. See, the volcanic crater was plugged by solidified magma from a previous eruption,. In the months before the eruption new magma was being pushed up the volcanic pipe, and when it reached the plug, the magma was pushed into a weak area of the volcano, which was where the bulge formed. When the earthquake occurred it caused the bulge to become completely unstable and collapse which then triggered the eruption.

[@ChuckD59]

@@ssoltau9318 Agreed if we agree "collapsed" equates to my "sloughed". The difference being: another definition of "collapsed" is to implode, which obviously did not happen. It literally slid off the mountain, triggered by an earthquake beneath that destabilized what little stability it had at that point. I'm not a geologist or volcanologist, but I have hiked around it several times, fascinated by the mechanics of this calamity.

[@ssoltau9318]

@@ChuckD59 It's not exactly like a building collapsing, it's more like as you said that part of the mountain slid away. To me it just looks like part of the mountain "collapsed". There's a series of photos made that shows the northern part of the mountain "collapsing" or sliding away. Also at 1:20 you can see in the animation that part of the mountain slid away. From above it would have seemed like the mountain was collapsing, which it somewhat did, at least in geological terms.

[@ChuckD59]

@@ssoltau9318 In any case a stunning example of how puny we as humans are. Everyone should get a chance to at least drive up Windy Ridge road to see the scale of this thing. Just no way to truly portray it in pictures.

[@FeR-kt1jt]

@@ChuckD59 someday!! I bet it's breathtaking

[@DwayneAPurple]

actually the last eruption before 1980 was in 1857. The mountain slept for 123 years.

[@hoffer54]

Amazing, thanks!

[@tonyvent3238]

Meravigliosa animazione Grazie x averlo condiviso

[@migram4190]

Never thought lahar flows could reflect back up a mountain

[@PeterPatterson-vt2cx]

Thank you.

[@XenoFireStar]

the only thing about your videos that I don't understand is the vertical scale. In every single one, your mountains are way too steep and pointy. Mountains don't often take the form of traffic cones, and look more like hills.

[@firstnamelastname3574]

EXACTLY! WHAT DID THEY USE? AN ETCH-A-SKETCH?? And what is MORE amazing? SOMEBODY PAID for this video to be made!!!! I watched 1 minute of this CRAP, AND, I would NOT give one penny for it!??!!

[@muxpux]

XenoFireStar the vertical scale is a jarring visual, sure, but if it’s flattened, it loses its effect. Exaggerating the vertical scale makes the subtle elevation changes more noticeable.

[@bobgreene2892]

":Meanwhile, the volcano embarked on another cycle of regrowth..." ---------------------- At 3:45, that additional activity seems represented by a flow of a different pattern, but none of that is detailed/explained. Has any flow comparable by even a fraction to the original eruption occurred since 1980?

[@satsat247]

Yes

[@mannyhood6024]

Good job!!

[@alicesacco9329]

I think if St Helens didn't grow a bulge, it's eruption would have been like 10 times more powerful.

[@bergydermeister5616]

Bulges Those are good

[@agustin.525]

why?

[@FeR-kt1jt]

@@agustin.525 the bulge meant lava was blocked from the top by rock and old lava.. If it blew threw the top, it's taking all of that too . The bulge was bad because of the debris flows and lateral blast. The bulge caused more deaths with less power.

[@Sebastianator01]

Ingomar200 coming in wit the best tsunami vids

[@ford9125]

Very interesting, but you forgot to take into account the massive lateral blast that propelled the flow to an estimated speed of 670 mph.

[@loopbraider]

that lateral volcanic blast (which was triggered by the landslide) was airborn, it was a completely different "flow" than the landslide - a landslide can't move that fast...the landslide started before and kept going well after the eruption blast flashed over it. Quote from a scientific site: "The Landslide was one of the largest in recorded history, traveled at 110 to 155 miles per hour." The volcanic blast went a lot further and faster, but even so it was nowhere near the largest volcanic eruption in recorded history like the landslide was.

[@JoeyHazboun]

loopbraider,very stupid huh.

[@hoffer54]

?

[@iqbalali7891]

Maybe another 123 or 130 years from that time, it will erupt again? Hopefully, it will not... Btw, this is cool though.

[@mariadelrosariomenendez326]

Lindo documental, subtitular en español, por favor

[@bergydermeister5616]

Harry's abode

[@Oxurus]

mind if I ask what program these simulation's are?

[@OfflineDisconnects]

In 1980 The Mount saint Helens eruption just caused a tsunami, (mega tsunami)

[@pidginmac]

What’s with the connect-the-dots animation at the start?

[@frankenz66]

Have glaciers started growing back yet?

[@muxpux]

Franklin Taylor yes, there is a glacier in the crater itself, and a few on the slopes

[@murraymachado401]

Heck, it's highly likely that the Old Man was washed clear into the sea. The biggest recorded landslide ever.

[@ssoltau9318]

I don't think so. His lodge was right next to Spirit Lake. The landslide obliterated the lodge. It's possible that he may have been on an early morning walk, but even then It's highly unlikely. The landslide would have obliterated him as well, I doubt there was anything left of him ether way.

[@stfjinkiojd]

@@ssoltau9318 Whatever is left of him and his lodge is under some 200 feet of rock. The bottom of today's lake is higher than the surface of the old lake

[@valdircarlos6769]

Muita paciência.

[@pavlovsworld9122]

U missed the earthquake which caused the collapse and sent the glacier into the chamber causing the explosion

[@ssoltau9318]

It wasn't really the glacier. The magma itself was already under extreme pressure and full of dissolved gas like carbon dioxide and water. Yes, water. Magma coming from the mantle has water dissolved in it. Some of it is from when the earth formed, while the rest is from the Cascadia Subduction zone. The rocks that form the oceanic crust has a lot of water in it, and when it melts in a subduction zone the water is released reducing the melting point of the rocks a little bit more. The magma and dissolved water rises up, then it either pools in large chambers and cools, or it continues up and erupts at the surface. Anyway. Just before the eruption there was a magnitude 5 quake, which caused the bulge on the north side of the volcano to collapse. This reduced the pressure on the magma, this also reduced the pressure on the dissolved gasses in the magma, causing them to explode from the magma, blowing it into ash. It's like shaking a champagne bottle and then removing the cork, all the gas in the champagne causes it to blow out. The glacier itself had little effect on the main eruption.

[@pavlovsworld9122]

@@ssoltau9318 The point of my comment was that he missed that there was an earthquake which caused the collapse and the dominos to fall. Pretty major piece I just learned myself and thought he could enhance his description.

[@ssoltau9318]

@@pavlovsworld9122 True, even so the glacier itself would have had little effect on the eruption itself. By the time the glacier would have gotten to the magma chamber, the eruption was already in full swing though. Water can enhance an eruption though. But I do see your point.

[@pavlovsworld9122]

@@ssoltau9318 ya. The collapse by the earthquake would have set the eruption in motion. But also Helen's had been dealing with geothermal heat caused by repeated melting and freezing of the ice over the decades building up immense pressure. But the fissures hadn't been exposed so the glacier acts like a pressure cooker only allowing some interaction between the chamber and the ice. The earthquake would have opened up those fissures and allowed tonnes of ice to suddenly enter the chamber. This reaction is part of what we see with those huge explosions. Lava and ice react. It wa incredible.

[@jamesbilof4201]

ZOUNDS!!!!!!!!

[@deadly_pikachu]

Much of the north side more like all of it

[@deadkemper]

to fast to keep up with in detail

[@SumDumGy]

*pausing is an option

[@juroramsiswisnuwardhana6232]

Where is tsunami

[@dwpalme2670]

Your timing is way off. It broke over the ridge behind Spirit Lake within 30 seconds; that means Johnston Ridge was gone in less than 25.

[@jamesbilof4201]

ZOUNDS!!!!!!!!

[@jamesbilof4201]

ZOUNDS!!!!!!!!