Major Explosion at Chaiten Volcano (Update)

Mod edit: Changed title from "Chaiten Volcano Magma Chamber Identified?" on author's request. Update here

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One of the biggest questions today for anyone following volcanoes is how big the Chaiten eruption will be. Nobody knows much about the volcano. What we do know is that it had been 9,000 years since the last eruption and that it hasn't stopped erupting since it started on May 2nd. There are also signs that something worse is coming. As I posted in another thread here is what John Seach had to say about the volcano.



Source: www.volcanolive.com...

The eruption has been big. There is no doubt. I have seen reports online that the first part of the eruption may have ejected as much as 2 km^3 of material which is nearly twice as big as Mount St. Helens. A second and more explosive phase started about a week later and was bigger than the first phase. So just guessing it may have ejected 5+ km^3 of material already.

Then I find this quote....



Following that the page includes a quote from Seach's website which lists five large quakes that preceded the eruption.



Source: www.seablogger.com...

The source above theorizes that the points may mark the outline of the magma chamber. Is that accurate? I don't know. But lets assume for a minute that it is. I plotted the points to get a visual of what the surface area of the chamber would look like. It would be oblong. From the widest points it would stretch about 45k and the narrow points about 30km. Give or take a couple km. I calculated the estimate surface area to be about 460 km^2.

How to figure out the volume of something like that? It won't have the same height from top to bottom all the way around. I imagine it to be like a hot water bottle filled up. That doesn't really help me much. I wasn't very good in geometry back in the day. So I borrowed a little help from the USGS website. I noticed that the Yellowstone caldera had roughly the same shape. It was 60km at its longest point and 40km wide. It is estimated that the chamber is 10km from top to bottom. Figuring the volume of a cube you'd take 60 x 40 x 10 to get 24,000 km^3. Obviously it isn't a cube. The USGS estimates the chamber to be 15,000 km^3. In this case 62.5% of the cube volume. With the appearance being theoretically similar I applied that to the Chaiten system. I estimated 45 x 30 x 5. I assumed the smaller chamber wouldn't be as deep so I cut the height in half. That would give a cube volume of 6750. Taking 62.5% of that would give us a volume of 4,219.

Assuming those large quakes actually mark the outline of the Chaiten magma chamber and assuming it is shaped like the Yellowstone magma chamber and only has a depth of 5km then the chamber could in theory hold over 4,000 cubic km of magma.

There is no way to know for sure until this is over. But the eruption has been going on for 2 weeks. It is still going strong. The only end in sight might be a catastrophic explosion and a collapse of the volcano itself which will do god only knows what. We do know that the volcanic system already has a caldera that is 3km wide. Who knows how much magma has built up in 9,000 years. But based on what Seach has posted things don't look good. It has gotten interesting enough that the USGS has just sent a team down to study and observe the event.

Sorry for the long winded post.

[edit on 2008/8/1 by Hellmutt]

reply to post by Indy

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Wow great post. I was just on here before class looking up information on Chaiten. Oddly there isn't alot of coverage on it. Now this b*tch is big and pissed! I heard in your post your compareing it to Yellow stone. I am not an expert but if it were anywhere NEAR yellow stone i think we would have at least a CNN coverage...but then again considering all of the recent activity i think there hands are full. Starting today they think the big eruption is going to take place any day now. Im keeping my eye on this one. (0)_(-)

The comparison to Yellowstone is more about the shape of the magma chamber and not the size of it. Sorry if that wasn't very clear in the original post.

How does chaiten volcano compare to say, Krakatoa? I have been keeping an eye on this situation, what little news we do get, does sound like something big is on the horizon.But could it really blow big time, and to what comparison? I read somewhere that it was unlikely to cause any major enviromental damage, other than surrounding areas. It is all very exciting all the same, and I log on every day to check up on progress, its intersting that it has basicly been continuously rumbling and belching ash etc for two weeks non-stop. What is the end result? will it just rumble out and calm down? I also read that it was at a critical stage, does this mean after two weeks it has nearly exhausted itself? There sure is a lot of activity around the world at the moment. I suppose we will have to wait and see. I actually really hope that it blows big time, I mean, really, I do. I would love to see that, even just on tv. I'm sure that they have evacuated everyone by now, so no-one would get hurt. The sheer power of nature is truly awesome, and I mean napolian dynomite awesome!!!!

On a daily basis I been checking up on the volcano doing the google search "Chaiten Volcano" in quotes, but in the past week new information has been very hard to come by. So I did the search different with the ` above the e, ie:"Chaitén Volcano" and I started coming across Chilean websites having more recent information. Hope that helps you volcano watchers.

reply to post by skribal

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The only thing is that evacuated zones do little to protect people when large scale eruptions come into the scenario. For example with Krakatoa, the actual pyroclastic flows went across the water to nearby islands. Also never underestimate how far those things can go, or where, would seem a lesson Volcanologists have learned, the hard way in some cases. they can infact go uphill with enough energy behind them, which is a major issue with getting away from them, especially when considering they travel at high speed.

As well as that the ash cloud is a hazard as well, and lahars afterwards. Though as it's near the sea the lahar risk might be a bit less than in other cases.

Amazing post, lots of info, I feel with all the natural disasters and jazz happening around the world this will be another one to put on the list of things to watch. Would be awesome to find some pictures of it, even in its current state...

Edit: oh just found some, god what a stooge... google solves 80% of the questions I got

[edit on 21-5-2008 by Spock Shock]

volcanism.wordpress.com...

It could be that the eruption conduit is being blocked off. That could result in the eruption ending or a massive explosion depending on how much pressure gets built up.

reply to post by Indy

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Or the eruption stopping and then Exploding spectacularly in a massive pyroclastic ball of hell at a later date.

Here it is June 17th and Chaiten is still erupting. It looks as if additional vents have opened. For a while it looked like the eruption may be ending and now it looks like it may be getting worse. The eruption has been going on for 6 weeks solid now.

So do you think this will reduce global warming for a couple of years?

If it blows, I suspect we will get significant further weather pattern changes. I doubt anyone knows what effect a South American volcano would have on global weather.

here is a webcam of the eruption, with a delay of 10-15 minutes. when you press the link, wait for the thumbnails to load then press 'empezar' to play the movie of the past couple of hours eruption.

www.aipchile.cl...

Great post indy!
I watched the supervolcano nova/pbs special last night. Can be viewed in entirety at novapbs.org.
A blown caldera was estimated to have 1000 times the force of an active volcano.
Was a beautiful piece of scientific forensics to show 'Tobou' in sumatra cast a pall on the earth 75,000 years ago.
Causing the last ice age.
I don't often recommend anything, but this is a must see.

[edit on 6/19/2008 by jpm1602]

Can you post a link to the page that actually contains the video? I have hunted and I can't seem to find out. Would love watching it.

Thanks in advance.

Sorry for the delay indy...been yacking my ak's freind ear off on messenger. I have link. But gosh darn it only a preview and airing schedule! They almost ALWAYS have video casts. www.pbs.org...
First column....'mysteries of the megavolcano'.
Click on story, enter zip will give you schedule of airings. Coming on twice more here in cleveland in next few days. Sure it will where you are if in states. Usually after it runs, then they put to archives for viewing...like the string theory special.

[edit on 6/19/2008 by jpm1602]

[edit on 6/19/2008 by jpm1602]

It has been a while since this thread has been updated and it really needs it. Here we are approaching August 1st and this eruption is almost 3 months old. It has gone nonstop since it first erupted in the early days of May. Now there were hints that the eruption was about over a couple of weeks ago and something changed. Seismic activity picked up dramatically.



Source: volcanism.wordpress.com...

Credit also goes to Fresh Bilge for constant updates since the eruption has started.

At the beginning of this thread I calculated the theoretical volume of this chamber. This eruption hasn't come close to emptying out what the chamber could hold. But it also isn't ever yet. Why are they hearing this rumbling? Is there magma on the move? Is the system getting ready to explode because of a huge buildup of pressure? Or is the rumbling the beginning of the collapse of the system into a new caldera?

Has anyone else come across news on this eruption? I'd love to hear from members in Chile.

Oy! It might explode at any time...


Chaitén Update 42

Oh, great! A supervolcano is just what the world needs right now. Compare the potential of Chaitén with Tambora's 1815 eruption, which caused "the year without summer".


Wikipedia: Mount Tambora


...and this:

Maybe Mother Earth is about to fight back against manmade global warming?

Here is Chaiten news from the Fresh Bilge blog that has done such a great job of updating us since the eruption started. It isn't good news either.



Source: www.seablogger.com...

I don't really know how big this explosion was. Web cam view is pretty bad right now and I can't find the satellite image of the eruption. Guess we'll have to wait for more news.