Yellowstone Supervolcano

Discussion in 'Earth Science' started by Wolfboy, May 25, 2004.

  1. Starthane Xyzth returns occasionally... Valued Senior Member

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    It wouldn't be the end of the world, not in Biblical or sci-fi terms. Life would carry on. we would just have to deal with a lot of hardship for a few years, and many people would inevitably die.

    Civilisation continued despite the world wars.... an unprecendented natural disaster, like a Yellowstone supereruption, would be another black spot in human history. Not the end of it.
     
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  3. Facial Valued Senior Member

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    Agreed.
     
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  5. Novacane Registered Senior Member

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    Just think of 'TOBA' circa: 72,000BC. Another 'big' sumatran earthquake along the same faultzone that TOBA is on, then watch out.

    Novacane

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  7. tablariddim forexU2 Valued Senior Member

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    The chances of Yellowstone blowing its top over the next few thousand years is exceedingly low(official sources); don't let senstionalist media reporting get to you.
     
  8. Novacane Registered Senior Member

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    I guess it's not 'Sensational' unless it blows it's top again.

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    Novacane
     
  9. tablariddim forexU2 Valued Senior Member

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    No that would be Spectacular! The media likes to create sensationalistic Wonder, blowing things up out of all proportion and feeding us the fodder of paranoia and false excitement; misinformation abounds as they rake in billions turning us into insatiable voyeurs, rabid consumers and enlightened idiots. I don't believe more than 3% of the bullshit they spout on a daily basis and even that is probably more than I should believe.
     
  10. Red Devil Born Again Athiest Registered Senior Member

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    I caught half a news item a while back about Yellowstone and the likelihood of a volcanic eruption. From what I heard, one was expected and it would be quite a "biggie", nothing heard since though.
     
  11. Novacane Registered Senior Member

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    I would bet my money on the supervolcano TOBA (circa: 72,000BC) erupting again before Yellowstone, as a result of another potential series of big 9+ mag. earthquakes occuring nearby on the same sumatran faultzone that generated the last two big ones this past year.

    Novacane
     
  12. Red Devil Born Again Athiest Registered Senior Member

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  13. Judas_Noose Registered Member

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    All very interesting hypotheses - by the way - LOVE the handle "Hypercane" ... nice - While there is significant evidence to suggest that there was an impact of great magnitude at Chuxilub, perhaps the Iridium layer, which is quite fractured and inconsistent, was broken by tectonic faulting? I haven't seen anyone suggest this.

    Also - Someone previously mentioned that a few magnitude 6 quakes near the Yellowstone caldera would rupture the magma chamber that we know lies beneath it, was there not a magnitude 6 or greater quake within the park in the last 100 years? It did affect the timing of manyof the geysers, and even closed the top observatory deck of the visitor's center, but it didn't cause a magmatically-induced eruption.

    Quakes do not cause eruptions - or at least, this is our current undersdtanding of such things - But, quakes, and the seismic waves that accompany them (P, R, S, and L waves) can indicate if the tremors are harmonic and resonating within a submerged magma chamber.

    Yellowstone ... I don't know ... but that sure would be one hell of a show.
     
  14. MetaKron Registered Senior Member

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    They keep talking about the chances being low, but we don't know when it's going to blow and it can be set off by deliberate human action. There are several arsenals around the world that have what it takes to blow the lid off that soda pop bottle. The magma chamber is 8,000 feet down. Even our own air forces do not have the power to stop a determined cruise missile type attack aimed at the thin layer of dirt and rock that protects us from an eruption. For a guesstimate, 8,000 feet, approx 5 grams per cc, 5 times the weight of the equivalent depth of water, works out to 20,000 PSI of pressure on the gases in that magma.

    Of course, a single heavy duty nuclear weapon would peel it right open. We have nuclear weapons that can vaporize the entire magma champer, which is a frightening thought. I have no idea if that would be more or less damaging than the volcano going off in its own way.
     
  15. thedevilsreject Registered Senior Abuser Registered Senior Member

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    americas economy would pretty much disappear overnight with the ashfall over the farms out on the praries, remember that volcano ash is not the same as your grandparents remains
     
  16. Buffalo Roam Registered Senior Member

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    After Mt. St. Helens, the crops around the nation were the best they had been in decades, the ash makes a wounderfull fertilizer. The frutes and vegetable were the best for many years after.
     
  17. thedevilsreject Registered Senior Abuser Registered Senior Member

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    really, i watched a documentary that said that the ashfall would harm the crops in the praries
     
  18. MetaKron Registered Senior Member

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    With Mt. St. Helens the ashfall was very light, enough to add minerals to the soil without physically damaging the crops. It formed a gritty layer on cars that had to be washed off carefully or it would scratch the finish. It's also not the only volcano that went off in the Northen Hemisphere during the 1980s. We had more than one ashfall that could be detected in Kansas.

    No matter how good the content of the ash is for growing plants, several feet of it would smother everything but trees. It would not be good for the trees either if the trees had leaves. I don't know how long it would be before rivers and lakes recovered, either. Most of the fish would die and it may be the end of salmon too.
     
  19. valich Registered Senior Member

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    Where did you hear this from? We were pretty thorough on this subject last year with Ophiolite, Invert Nexus and I exchanging punches and views. The socalled Yellowstone volcano magma plume actually is just a small part of a much larger hot spot "the Yellowstone caldera" that extends west under the Snake River Plain but is only now recently centered over Yellowstone. This same caldera created the famous "Craters of the Moon National Park" in eastern Idaho.

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    Map of the Snake River Plain and the corresponding path of the Yellowstone Caldera. Source: http://en.wikipedia.org/wiki/Snake_River_Plain

    I still really doubt that there's going to be a "super volcano" there. There's a ton of igneous volcanic basalt covering the Craters of the Moon National Park but the volcanoes are only about 20-30 ft. tall. These were all formed by the same caldera (actually an upper-mantle convection current or "trailing plume" of magma) that's now centered over Yellowstone. So what's the difference that the erruption would now be more massive, or explosive, than it was ~700,000 years ago in the Snake River Plain? There's no active plate tectonic boundary there that would increase the pressure or explosive potential.

    Then again, if you've ever been to Yellowstone you know how much you can smell the sulfuric gases (and probably some methane too) bubbling out all those hot springs. The fumes can be overwhelming. And that'd be enough to knock out a few animals if they tended to venture near.
     
  20. valich Registered Senior Member

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    Correction: The Craters of the Moon National Monument was created by the same caldera hot spot "10 to 11 million years ago (meaning Craters of the Moon once looked like Yellowstone does today and Yellowstone will one day look much like Craters of the Moon does now) but 'moved' as the North American Plate migrated northwestward (actually the hot spot stays in the same place while the overlying continent of North America moves). Pressure from the hot spot heaves the land surface up, creating fault-block mountains. After the hot spot passes the pressure is released and the land subsides (this is in addition to caldera-created subsidence)." See: http://en.wikipedia.org/wiki/Craters_Of_The_Moon_National_Monument

    Also, as posted on Wikipedia (http://en.wikipedia.org/wiki/Yellowstone_Caldera), there are now three overlapping calderas at Yellowstone, so this could increase the potential. Sorry I don't have time to look into this further but I'll be travelling up there next week if anyone wants a personnel appraisal?
     
  21. doodah Registered Senior Member

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    Valich
    Glad to see you posting on the Earth Science threads again.
    Your corrected post is far more accurate than your first post today. I do have to take exception to one uncorrected statement in your first post- Craters of the Moon erupted only 1500 to 2000 years ago, not 700,000 years ago.
    The question is not "if" another catastophic caldera eruption will occur in the Yellowtone system, but rather "when". Even though they may have the same ultimate heat source, the silicic caldera eruptions are completely different from the later basalt (Crater of the Moon type) eruptions. Silicic magmas are high-viscosity- capable of building up huge reservoirs of volatiles resulting in catastrophic eruptions. Basalts, on the other hand, are low-viscosity, rarely explosive, and tend to form flat surface features (Hawaii, while not a "flat" feature, is still a shield volcano with relatively gentle slopes).
    A recent paper in Nature (Wicks, et al), suggest hydrothermal fluids were probably responsible for the 2003-2005 activity and uplift detected near Norris Geyser Basin. This uplifted "dome" is currently undergoing deflation- but other areas of the caldera are uplifting rapidly. For a summary of current activity in Yellowstone: http://volcanoes.usgs.gov/yvo/2006/uplift.html
    I recently reviewed a paper (currently "in press") that suggests the next caldera cycle may have already begun in Yellowstone. The authors do not indicate an eruption is imminent- in fact they suggest thousands to tens of thousands of years.
     
  22. valich Registered Senior Member

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    Actually I posted the second one immediately after the first as I try to be a stickler when it comes to the facts. I corrected my post according to what was posted on Wikipedia and that source is questionable. I definitely question their posting of a picture that states there are now three calderas overlapping Yellowstone. I think it's all the same one. Their map of the socalled "three calderas" only outlines two calderas and the Yellowstone caldera is inclusive of the same Snake River Plain caldera. They don't show three.

    I'm confused as to what you are saying. The Snake River caldera, now called the Yellowstone caldera, produced low-viscosity, minimally-explosive basalt flat-surface features at the "Craters of the Moon." Why do you expect it to be different at Yellowstone?

    The link that you posted, to my surprise, even reinforces what I am saying. They describe the activity at Yellowstone as a "hydrothermal activity," with the hot spot. That certainly explains the type of hot springs you find there. They state:

    "Scientists agree that a fluid has moved into the region, causing an increase in volume within the upper 15 km of the crust. Wicks et al. (2006) propose the idea that a small amount of basaltic magma (molten rock) has moved out of the main caldera (causing the ground to subside) and into the area north of the caldera (causing the ground to move upwards). They discern that the magma moved along a northward-dipping sill (sub-horizontal crack) located about 12-15 km beneath the ground surface. In the past, some scientists have preferred models where deformation at Yellowstone is caused by movement of hydrothermal fluid (hot water) or gas, rather than magma. For example, Waite et al. (2002) discussed a swarm of earthquakes that occurred in the western part of the caldera, that coincided with a change from uplift to subsidence in the caldera. They suggested the swarm was caused by movement of hydrothermal fluids (hot waters and gases) from inside the caldera to the northwest. Both types of fluids (magmatic and hydrothermal) may occasionally cause the observed deformation at Yellowstone. Scientists will continue to collect information that can help discriminate among the various possibilities."

    So now we have evidence that it may not be a magma plume, nor even a magma "hot spot," but may be strictly hydrothermal. Great link: 2006.
     
  23. Novacane Registered Senior Member

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    One way to confirm it. Grab a shovel and start digging in Yellowstone, down to a depth of approx. 8,000 feet. If you see a lot of hot boiling water and steam squirting up at ya, then start running. The same goes for the magma too

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