Supervolcanos

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Offline Les the Scientist

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Supervolcanos
« on: 11/11/2004 00:35:18 »
Is it likely that Yellowstone National Park will erupt in my lifetime ?
 

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Offline neilep

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Re: Supervolcanos
« Reply #1 on: 11/11/2004 09:20:20 »
As far as I understand the possiblity is Yes....I can't remember the exact figures but it's either every 100,000 or 5/600,000 years and the time is now, or, it's 100,000 years overdue ......How comforting !!...poor Yogi and Boo Boo !!.....I will check my figures but as far as the time being due, I'm sure I'm accurate. I believe it was quite a startling revelation as the chappy who discovered it had to see it form a plane/helicopter when it dawned on him that it was in fact the whole area of Yellowstone Park, when in fact they had been searching on a much smaller scale.

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Offline Exodus

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Re: Supervolcanos
« Reply #2 on: 11/11/2004 11:09:45 »
we were made aware fairly recently that yellowstone is in fact showing signs of activity. A surveyor was mapping the area and taking height measurements. He noticed that his readings were generally considerably higher than a survey conducted in the last century. He was so convinced that he must have made an error that he actually surveyed the site again. The penny dropped when he extended his area and found large areas of previously dry forest flooded and a small boat jetty also under water. Due to a phenomenon called bradyseism the crust in the park has swollen and risen. This is due to the filling of a magma chamber bellow the surface which cuses the crust to bulge. People shouldn't panic though, bradyseism happens fairly regularly in calderas and magma can just as easily cool and sink back down into the mantle and thus lower the bulge once again... think of it like the volcano breathing.

I'll say this though, i doubt you'll see it go off in your life time, geologically speaking its not that overdue. If it DOES go off then not only are you Americans pretty screwed, but the world will also be in BIG trouble. A Yellowstone eruption will be explosive, throwing dust high up into the atmosphere which will block out the sun.

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Offline neilep

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Re: Supervolcanos
« Reply #3 on: 11/11/2004 19:25:31 »
quote:
Originally posted by Exodus

 A Yellowstone eruption will be explosive, throwing dust high up into the atmosphere which will block out the sun.


And it will also be bad news for sun-block cream manufacturers too [:D]...sorry !!......[;)]

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Offline Ercole

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Re: Supervolcanos
« Reply #4 on: 21/01/2005 09:26:10 »
The next rain after this mega-eruption will surely improve umbrellas manufacturing... Using steel of course !
« Last Edit: 21/01/2005 09:27:07 by Ercole »
 

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Offline Jel

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Re: Supervolcanos
« Reply #5 on: 10/03/2005 21:56:01 »
Yellowstone is not, however, the only one: Vesuvius seems to have developed a larger chamber underneath, and its proximity to the sea could cause secondary problems to the western Mediterranean coastline. Does anyone know where the others are?
 

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Offline neilep

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Re: Supervolcanos
« Reply #6 on: 10/03/2005 22:30:58 »
I'm sure I heard on the radio last night that there's another one in New Zealand...but certainly not on the scale of YellowStone.

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Offline FlyDutchMan

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Re: Supervolcanos
« Reply #7 on: 11/03/2005 01:46:19 »
I'm from New Zealand... we do have a supervolcano called Taupo (currently its a lake). It had a minorish explosion (100km3) in 186AD and the chinse felt it and noted red skys and colder temps for the next few years. It has a history of blowing every 2000 years or so, and its largest eruption was 26,500 years ago (called Oruanui)- the third largest known eruption ever. That eruption was only a bit smaller than the Yellowstone one 1.3million years ago - 800km3 as opposed to 1000km3.

I've attached a map of the area, the large lake in the middle is taupo and northen edge is made up from aseries of caldera from more recent explosion.
 

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Offline neilep

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Re: Supervolcanos
« Reply #8 on: 11/03/2005 02:09:58 »
That's fantatstic FlyDutchMan....thank you very much and welcome to the forum.

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Offline Bass

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Re: Supervolcanos
« Reply #9 on: 29/03/2005 05:48:13 »
As far as known active "supervolcanos", don't forget Long Valley, Calif., Toba in Indonesia and Rabaul in Papua New Guinea
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Offline chris

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Re: Supervolcanos
« Reply #10 on: 29/03/2005 08:51:50 »
Hi Bass

I didn;t know about any of those - do tell more.

Chris

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Offline Bass

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Re: Supervolcanos
« Reply #11 on: 29/03/2005 18:45:21 »
Long Valley is located near Mammoth Mountain in California's Sierra Mountains.  While Mammoth is well known for it's skiing, the area is less well known for the Long Valley Caldera.  Last major eruption was about 760,000 years ago with an estimated volume of 600 cubic km.  Deposited the Bishop Tuff.  Long Valley and Mammoth Mountain are still active- the USGS established the Long Valley Volcano Observatory to monitor activity.
Toba, located on Sumatra, Indonesia, has been called Yellowstone's big sister.  Last erupted around 74,000 years ago with an eruptive volume of 2800 cubic km (compared to 2100 cubic km for Yellowstone's largest eruption).  It is thought that this eruption almost caused human extinction- collapsing the population to a few thousand individuals.
Rabaul in Papua New Guinea probably erupted around the 6th century.  While not as large as some "supervolcanoes", it is very active (large eruption in 1994) and is mostly underwater- which gives it the potential for explosive eruption.
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Offline OldMan

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Re: Supervolcanos
« Reply #12 on: 30/03/2005 04:06:23 »
Forgive my seismic ignorance but the recent quake to hit Indonesia (8.7 was it?) isn't any sort of indicator or trigger to such volcanic activity is it?

Please say "no Tim you're a fool no go back to hiding under your rock!"

It has been too long since what little they taught in school about such things.

Tim
« Last Edit: 30/03/2005 04:07:06 by OldMan »
Tim

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Offline daveshorts

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Re: Supervolcanos
« Reply #13 on: 30/03/2005 14:46:42 »
If I remember rightly from my first year Geology course, seismic activity can be indicative of imminent volcanic activity, as moving magma tends to stress and crack the surrounding rock, but really big quakes like this one are associated with plate boundaries, where you have massive lumps of rock grinding against each other under pressure, and are not directly associated with volcanos. The stresses produced by moving magma are just not big enough to produce this size of eathquake.

I suppose if a nearby volcano was about to go off a big earthquake could trigger it, but it would have gone off in the next couple of years anyway.

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Offline Bass

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Re: Supervolcanos
« Reply #14 on: 06/04/2005 05:44:15 »
The bad news is that the two big quakes have increased stress on the fault that runs down the spine of Sumatra- increasing the likelihood of another large quake in the vicinity of Toba.
The good news is that Toba's eruption cycle is around 300,000 years and it last erupted around 74,000 years ago.  So I guess its safe to quaff down a few Fosters for the next 200,000 years or so, even if your glass is upside down.

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Offline OldMan

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Re: Supervolcanos
« Reply #15 on: 07/04/2005 03:58:02 »
Fosters[xx(] they still make that stuff?[:0]

Tim
Tim

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Offline Bradley5

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Re: Supervolcanos
« Reply #16 on: 11/04/2005 06:46:24 »
Could Toba be on a countdown to another eruption with all of this earthquake activity?
 

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Offline chimera

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Re: Supervolcanos
« Reply #17 on: 13/04/2005 03:18:11 »
quote:
Originally posted by OldMan

Forgive my seismic ignorance but the recent quake to hit Indonesia (8.7 was it?) isn't any sort of indicator or trigger to such volcanic activity is it?
Please say "no Tim you're a fool no go back to hiding under your rock!"



Eeerm. [}:)]

http://www.newsday.com/news/nationworld/world/wire/sns-ap-indonesia-volcano,0,837593.story?coll=sns-ap-world-headlines
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Offline ADD HAHAHA

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Re: Supervolcanos
« Reply #18 on: 13/04/2005 03:52:36 »
what if some one drop 1 of those nukes that puches holes in the gound on yellow stone or some other supervolc. [:(]
Drew Rody

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Offline chimera

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Re: Supervolcanos
« Reply #19 on: 13/04/2005 04:29:31 »
Don't worry, our nukes are puny stuff compared with such forces. The earthquake that caused the tsunami was in the order of 30,000 to 100,000 times the bomb on Hiroshima, just to give you an idea of how much bigger. If it was so unstable that even a nuke could make it go off, you don't want to be around anyway...
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Offline DoctorBeaver

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Re: Supervolcanos
« Reply #20 on: 13/04/2005 13:43:12 »
I know it's not a volcano (or, at least I don't think it is) but part of 1 of the Canary Islands is due to fall into the Atlantic at some point. That's predicted to cause a tidal wave that could devastate the Eastern seaboard of the USA
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Offline chimera

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Re: Supervolcanos
« Reply #21 on: 13/04/2005 19:37:24 »
Errare humanum esd.-- Biggus D.

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Offline DoctorBeaver

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Re: Supervolcanos
« Reply #22 on: 19/04/2005 02:23:12 »
chimera - interesting article: but there's obviously still a lot of contention about it
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Offline chimera

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Re: Supervolcanos
« Reply #23 on: 19/04/2005 11:04:42 »
Well, they were convinced for a while it was a ticking time-bomb. Now they're not so sure, but any large quake could still cause a big surprise, and suddenly gigatons of stuff slide into the Ocean. The wave would be over 100 meters up close and wipe out most of Western Morocco after an hour, would flood the Eastern American seaside heavily after 9 hrs or so, and even cause 6-10 waves as far away as the UK and Holland, where I live.

I'd still have a few hours to get to my boat, park it on the nearest large water and point my stern to where I suspect it would be coming from, and ride it out, though.

added: Anatomy of a Tsunami Disaster (1958)

http://www.drgeorgepc.com/Tsunami1958LituyaB.html
« Last Edit: 19/04/2005 11:12:53 by chimera »
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Offline Exodus

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Re: Supervolcanos
« Reply #24 on: 25/04/2005 14:15:04 »
Interesting how they are now saying its been hyped up... i still firmly believe it is possible. A little out of date i know, but the BBC did a very good Horizon programme in 2000 about La Palma in the Canary Islands.

http://www.bbc.co.uk/science/horizon/2000/mega_tsunami_transcript.shtml

This is the link if anyone fancies a read.

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Offline neilep

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Re: Supervolcanos
« Reply #25 on: 25/04/2005 16:48:15 »
I just watched the BBC two-part docurama funnily called ' Supervolcanoe ' (based on Yellowstone) ......and phew !!...well. when it goes, it'll go and we'll all know about it !!...it'll be a 'pack your bags and exit the planet' event....oh joy !!

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Offline Exodus

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Re: Supervolcanos
« Reply #26 on: 26/04/2005 13:59:25 »
There were a lot of things on that programme that were geologically very accurate, they did overdo a few things which i thought was a bit crap.

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Offline neilep

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Re: Supervolcanos
« Reply #27 on: 26/04/2005 20:26:01 »
quote:
Originally posted by Exodus

There were a lot of things on that programme that were geologically very accurate, they did overdo a few things which i thought was a bit crap.



Wocha Matey[:)]...I suppose they're allowed to use some dramatic license, of course you're expertly qualified to notice the exagerrations....but then even I noticed that the windscreen wipers were cleaning the volcanic ash too easily !![:D]

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Offline Bass

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Re: Supervolcanos
« Reply #28 on: 07/05/2005 05:36:14 »
Yellowstone Volcano Observatory geologist Bob Smith notes that Yellowstone achieves a "High Threat" ranking for volcanic eruption:

http://tv.ksl.com/index.php?nid=5&sid=203367


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Offline chimera

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Re: Supervolcanos
« Reply #29 on: 07/05/2005 10:08:53 »
Maybe you should look through all this 'warning system' nonsense:

in case they 'know' it's going to blow, they will never issue a warning: the panic alone would kill thousands, and then you'd still have the chance it was a mistake after all. And if it went off, who would care about such details anyway?

Honestly, they'd just get all their friends and family to safety and stay mum.

Not intended ironically, just simple experience with opportunistic gouvernment logic.

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« Last Edit: 07/05/2005 10:09:56 by chimera »
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Offline Deanwinfield

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Re: Supervolcanos
« Reply #30 on: 11/05/2005 20:20:58 »
what would happen to the UK if the supervolcano errupted in New Zealand? I presume the initial erruption wouldnt reach us, but the dust cloud or anything?

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Offline Bass

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Re: Supervolcanos
« Reply #31 on: 12/05/2005 04:38:20 »
An eruption in the southern hemisphere would have global effects.  First, the ash cloud blown high into the atmosphere would eventually encircle the globe.  Secondly, these volcanoes emit tremendous amounts of sulfur (which becomes sulfur dioxide).  Both the ash and SO2 will cause global cooling, possibly to the point of ushering in a new ice age.

As you no doubt know, Yellowstone sits on top of a "hot-spot"- the heated rocks produce a seismic low velocity zone beneath the Yellowstone area extending down into at least the upper mantle.  A somewhat similar low velocity zone has been recently discovered beneath the UK- perhaps in time you'll have your own version of "Old Faithful" (though I'm sure folks in the UK will come up with a much more humorous and descriptive name for such a feature).

Darn my computer skills, I seem to have lost the link to the article.  Will post again when I find it.

Found it at last    http://dsc.discovery.com/news/briefs/20050502/britisles.html
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« Last Edit: 12/05/2005 04:58:39 by Bass »
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Offline hate

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Re: Supervolcanos
« Reply #32 on: 12/05/2005 13:05:22 »
quote:
Originally posted by Deanwinfield

what would happen to the UK if the supervolcano errupted in New Zealand? I presume the initial erruption wouldnt reach us, but the dust cloud or anything?

"There is no gravity, the earth just sucks"



no, its 2 far away, just low temperatures, and yellowstone PROBABLY will not xplode in the next 500 years, caldera volcanoes take long time to erupt, the activity pre-eruption is really high a dome is formed weeks before the eruption, and then the area around the caldera start to crack, if u want to worry about something worry about the Vesuvius and Tangurahua(they will erupt in less than 10 years) and the poor bastards who live near them(more than 1.5 million around Vesuvius)
 

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Offline daveshorts

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Re: Supervolcanos
« Reply #33 on: 12/05/2005 13:21:19 »
Interesting though, it may explain why ireland is an island - If I remember my Geology lectures, the north sea was created when the Atlantic was forming, so europe was under tension and a hot spot softened the crust, so it stretched and got thinner forming the North sea. It then decided to break off Ireland instead - maybe there was another stage where it softened the crust under the Irish sea, thinning the crust again forming the sea.

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Offline DoctorBeaver

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Re: Supervolcanos
« Reply #34 on: 15/05/2005 22:32:03 »
I really must stop reading these forums. 1 post had a picture of really disgusting bug & now I learn I'm living on top of a supervolcano. Well thanks a bunch, guys - nightmare time!
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Offline Razor

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Re: Supervolcanos
« Reply #35 on: 10/08/2005 10:38:49 »
I've heard about those volcanoes,if Yellowstone park blows it would wipe out most of America for sure, and there's also the risk of another "Ice Age".
The thing that's most threatening is these Atomic Bomb Testings,or a bomb of similar Mass Destruction, i know a Powerful Bomb could set that thing off,and with it's overdue eruption?????
hmmm.....but then again, with all the daily suffering that occurs around the world......it's probably for the best....probably.[|)]

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Offline Razor

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Re: Supervolcanos
« Reply #36 on: 10/08/2005 10:41:48 »
And er....if anyone already mentioned anything that i've written then sorry! i just post my comments and leave.

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Offline David Sparkman

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Re: Supervolcanos
« Reply #37 on: 10/08/2005 12:19:33 »
I guess we should pass a law that volcanos are not allowed to pollute. But then again, if we are truly in a man made global warming, maybe Ma nature needs to make a correction. But then on the other hand, maybe we just don't know sh*t about planet and ought to just sit back and marvel that we are still alive after all those ice ages, warm spells, evil busiessmen, and do gooders have messed things up so badly.

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Offline Evie

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Re: Supervolcanos
« Reply #38 on: 10/08/2005 23:14:49 »
Let's see....my $0.02

The Canary Islands are volcanic...scientists are still puzzling over the particulars though(because it's not a traditional "hot-spot" model).

The Mt. St. Helen's eruption was actually caused by an earthquake. The mass wasting of the hillside lessened the pressure holding the magma in and CABLOOIE!

Here's a link for USGS info on the Yellowstone caldera...by the bye, it could blow at any moment! AAAAAHHHHHHHH!!!!!

http://vulcan.wr.usgs.gov/Volcanoes/Yellowstone/OFR95-59/OFR95-59_inlined.html

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Offline Razor

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Re: Supervolcanos
« Reply #39 on: 11/08/2005 00:16:36 »
Ok im gonna assume that you meant "By the way" lol[:D]!

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Offline hogbody

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Re: Supervolcanos
« Reply #40 on: 18/09/2005 06:25:19 »
Taupo was a huge eruption. A friend of mine showed a picture of the pyroclastic flow deposit that hit the side of a mountain about 90km away so hard that it overturned the soil. The ash layer was only .25m thick or so.

BTW, the Canary's are a "hot spot" volcano and the island of Brava has carbonites. Rather unusual.
 

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Offline niko

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Re: Supervolcanos
« Reply #41 on: 09/11/2005 19:31:41 »
it could blow today it could blow tommarow and we would not know until it happened and then when it happens there is nothing we can do to stop it just try and wade it out and try and servive
 

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Re: Supervolcanos
« Reply #42 on: 19/11/2005 07:19:33 »
quote:
Originally posted by Bass

As you no doubt know, Yellowstone sits on top of a "hot-spot"- the heated rocks produce a seismic low velocity zone beneath the Yellowstone area extending down into at least the upper mantle.  A somewhat similar low velocity zone has been recently discovered beneath the UK- perhaps in time you'll have your own version of "Old Faithful" (though I'm sure folks in the UK will come up with a much more humorous and descriptive name for such a feature).

Darn my computer skills, I seem to have lost the link to the article.  Will post again when I find it.

Found it at last    http://dsc.discovery.com/news/briefs/20050502/britisles.html



It does lead me to the question as to whether this is, at least in part, why the eastern seaboard of the UK is subject to significant erosion that is not a problem on the western seaboard – i.e. it has been said that the north west is rising and the east falling into the sea.
« Last Edit: 19/11/2005 07:53:30 by another_someone »

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Offline daveshorts

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Re: Supervolcanos
« Reply #43 on: 19/11/2005 10:41:28 »
If it is explaining the old volcanic features of the UK then it may well be left over from the forming of the atlantic ocean 60million years ago or so - I think the hot spot (upwelling in the convection currents in the mantle) that is now under iceland started off under the north sea, the plate was under tension so tried to split there (forming the north sea and indirectly all the oil in it) but ended up splitting off the W coast of scotland and ireland. If this is the case it is probably petering out, and if it is 250km down we have a while before we have to start worrying anyway.

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Offline A Big Mug

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Re: Supervolcanos
« Reply #44 on: 22/11/2005 03:43:44 »
Forget global warming for a minute.  OK?  Wouldn't it be interesting if the super volcanos eruption was the mechanism for warming the earth during the recurring ice ages?  What if the enormous weight of the ice on the earths crust somehow increased the likelyhood of an eruption.  Wasn't the ice miles thick around Yellowstone during the last ice age?  What if the huge amounts of ash spewed out during these eruptions fell on the ice around the world.  The darker ash captured more of the infra red energy from the sun and warmed.  It would contribute toward melting the ice exposing more land which would only continue the warming.  The volcanos also discharge a great deal of co2.

Suppose scientists dicovered that instead of global warming about the kill us the planet was about to enter another ice age that would kill us.  We almost had this a few hundred years ago.  Would anyone object to adding more c02 to the air to keep the planet from freezing?  Millions died a few centuries ago when the earth got cold.
 

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Offline Bass

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Re: Supervolcanos
« Reply #45 on: 22/11/2005 22:05:04 »
Actually, volcanos have the opposite effect- they cool rather than warm the earth.  Explosive volcanism injects ash and dust high into the stratoshpere, increasing the earth's albedo which leads to cooling.  Sulfur dioxide emitted during eruptions, also acts as a coolant.  Historical explosive eruptions all have demonstrated cooling effects.

Prediction is difficult, especially the future.  -Niels Bohr
« Last Edit: 22/11/2005 22:06:00 by Bass »
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Re: Supervolcanos
« Reply #46 on: 23/11/2005 02:24:20 »
quote:
Originally posted by Bass

Actually, volcanos have the opposite effect- they cool rather than warm the earth.  Explosive volcanism injects ash and dust high into the stratoshpere, increasing the earth's albedo which leads to cooling.  Sulfur dioxide emitted during eruptions, also acts as a coolant.  Historical explosive eruptions all have demonstrated cooling effects.

Prediction is difficult, especially the future.  -Niels Bohr



I thought it was more complex than that.  That initially volcanoes cooled the Earth, but the longer term impact (as the ash settles out) is to subsequently warm the Earth.

There are also quite significant differences in how explosive a volcano is, and the nature and amount of gas it expels.

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Re: Supervolcanos
« Reply #47 on: 23/11/2005 20:49:34 »
Nothng is simple
   (Well, my wife tells me I'm awefully simple at times)

Ash injected into the stratosphere causes the initial, yet short-lived cooling.  Volcanic gas, especially sulfur, is responsible for the longer-lived cooling effect.  Explosivity does not necessarily correlate with cooling effect- relatively non-explosive volcanoes may cool the climate dramatically due to sulfur emissions (Laki in Iceland and El Chichon in Mexico are good examples).  Also, latitude of the eruption is important in determining global cooling- high latitude eruptions don't have as much effect as low latitude volcanism (Katmai vs Pinatubo).

I've not read much about the subsequent warming effect of eruptions- I'd be interested if you have any sources.

Prediction is difficult, especially the future.  -Niels Bohr
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Re: Supervolcanos
« Reply #48 on: 25/11/2005 09:06:40 »
quote:
Originally posted by Bass
I've not read much about the subsequent warming effect of eruptions- I'd be interested if you have any sources.



Not trying to say that any of these sites have the last word on the issues involved, but they certainly do have something to say:

http://www.geology.sdsu.edu/how_volcanoes_work/climate_effects.html

http://www.emporia.edu/earthsci/student/sneed3/pinatubo.htm
quote:

These sulfate aerosols will also accelerate chemical reactions that destroy the ozone. Ozone destruction allows dangerous levels of ultraviolet radiation to reach the earths surface and can increase the risk of skin cancers. Mid latitude ozone levels reached their lowest recorded concentrations during 1992-93. The ozone hole over Antarctica became the largest ever recorded and in 1991 the ozone levels in the troposphere decreased in time with the Pinatubo aerosol arrival. Mt. Pinatubo 2001)
Carbon dioxide is the main greenhouse gas that allows a warming of the Earth. Volcanic gasses that are added to the atmosphere by volcanic eruptions increases this greenhouse gas and thereby the greenhouse effect. Initially the gaseous products cool the Earth for a period of 1 to 3 years. After the cooling effect is removed the increased carbon dioxide remains to potentially increase global warming.



http://hvo.wr.usgs.gov/volcanowatch/2004/04_03_18.html
quote:

Sulfur dioxide (SO2) is the main gas released by volcanoes that can affect climate in the short term. Chemical reactions that occur when SO2 reaches the atmosphere produce tiny sulfuric acid droplets called “aerosol.” Very energetic eruptions push the aerosol up into the stratosphere, the layer of the atmosphere from 10 to 50 km altitude (around 32,000 to 164,000 ft), where it inhibits the sun’s energy from reaching and warming the earth’s surface.
Once in the stratospheric jet stream, the aerosol quickly encircles the globe. The microscopic droplets tend to remain aloft for months to years, promoting global cooling.
In the longer term, huge volcanic eruptions can have another effect. The release of greenhouse gases, such as carbon dioxide, into the atmosphere can cause warming rather than cooling.



One question I have not seen asked, or answered, is the degree of purely adiabatic cooling that, at least locally and transiently, might occur in the aftermath of the release of pent up pressure from within a volcano.
« Last Edit: 25/11/2005 09:10:47 by another_someone »

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Offline Bass

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Re: Supervolcanos
« Reply #49 on: 17/02/2006 21:35:25 »
The USGS Yellowstone Volcano Observatory (YVO) released a statement in their January 2006 newsletter that continuous GPS stations are showing extremely high rates of uplift (4-8 cm) over the past 18 months in parts of the Yellowstone caldera.

"During the past year, continuous GPS stations have recorded between 4 and 8 cm of uplift over much of the Yellowstone caldera (except the northern part near the Norris geyser basin)."

http://volcanoes.usgs.gov/yvo/

http://www.mines.utah.edu/~ggcmpsem/UUSATRG/GPS/Site_Info/lkwy.html
The top two graphs show horizontal migration (N-S and E-W), while the bottom graph shows vertical change at the Lake Yellowstone GPS.

The YVO says this movement is within normal surface deformation patterns, but if earthquakes start accompanying the deformation, it may indicate possible magma movements.

Subduction causes orogeny.
« Last Edit: 17/02/2006 21:36:08 by Bass »
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