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Volcanoes May Have Caused Mass Extinctions?

Posted by Zonk on Fri Nov 02, 2007 02:55 PM
from the can't-breath-must-snack-on-mammals dept.
Hugh Pickens writes "According to recent research, huge amounts of sulphur dioxide released by volcanic eruptions may have had more to do with wiping out dinosaurs than the meteorite strike at Chicxulub on Mexico's Yucatán Peninsula. Marine sediments drilled from the Chicxulub crater have revealed that that the mass extinctions occurred 300,000 years after Chicxulub hit Earth. The Deccan volcanism was a long cumulative process that released vast amounts of greenhouse gases into the atmosphere. '"On land it must have been 7-8 degrees warmer," says Princeton University paleontologist Gerta Keller. "The Chicxulub impact alone could not have caused the mass extinction, because this impact predates the mass extinction."' Keller also postulates a second larger and still unidentified meteor strike after Chicxulub, that left the famous extraterrestrial layer of iridium found in rocks worldwide and pushed earth's ecosystem over the brink. But where's the crater? "I wish I knew," says Keller."
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  • The Chicxulub impact alone could not have caused the mass extinction, because this impact predates the mass extinction.

    For the Chicxulub impact to have caused the mass extinction, it *must* have predated the mass extinction. How's it going to cause a mass extinction if it takes place after the mass extinction occurs?
    • Doh... (Score:3, Informative)

      by Anonymous Coward
      How's it going to cause a mass extinction if it takes place after the mass extinction occurs?


      If you had ate least read the summary, you would have realized that this "predate" here means 300000 years...

    • by SnowNinja (1051628) on Friday November 02 2007, @03:05PM (#21216737)

      For the Chicxulub impact to have caused the mass extinction, it *must* have predated the mass extinction. How's it going to cause a mass extinction if it takes place after the mass extinction occurs?
      I think what they're trying to say is that 300,000 years is a little long to actually attribute the mass extinction to the meteor. If it were the direct cause, the extinctions would have occured in a much more narrow time frame.
      • >>I think what they're trying to say is that 300,000 years is a little long to actually attribute the mass extinction to the meteor. If it were the direct cause, the extinctions would have occured in a much more narrow time frame.

        I would Love to know the margin of error radioactive carbon dating has at a 65 million year old site, where other radioactive elements were deposited.
      • Apparently there's some controversy as to whether the gap is a result of normal geological activity or a direct result of the impact. See the last paragraph of this section [wikipedia.org].
    • by IdleTime (561841) on Friday November 02 2007, @03:15PM (#21216891) Journal
      Gerta Keller... *sigh*

      I think everyone should take her research with quite a few grains of salt, she has been in a bitter fight for years over this issue and she has been quite obnoxious when it comes to the topic of Chicxulub and mass extinction. Until this is confirmed by independent research, nobody should take it for gold.
        • Re: (Score:3, Informative)

          Aye! This is true.

          Esp. in this area since the two parties are so at the throat of each other that it is difficult to take anything they say for good fish. Gerta Keller is quite hateful and very angry because her funding was taken away after some umm unconventional outbursts from her side.
    • For the Chicxulub impact to have caused the mass extinction, it *must* have predated the mass extinction. How's it going to cause a mass extinction if it takes place after the mass extinction occurs?

      Geologic timescales. Here, 'predated' implies 'predated significantly enough such as to be unrelated.' This is understood by everyone who isn't trying to be as pedantic as humanly possible.

    • It's like you shoot your friend in the back tonight, and (s)he dies in 2010. It's not that your friend no longer died after you fired the gun, but rather the 2-3 year wait kinda cancels the 'smoking gun' effect.

      If, on the other hand, the prosecution produces evidence that you shot your friend in the head, and then your friend went into a coma for 2-3 years before dying, then they might still have good grounds for a murder charge.

      Such a coma effect might be if we could show that the 300,000 years of in

      • by YouTookMyStapler (1057796) on Friday November 02 2007, @03:18PM (#21216939)
        Volcanoes not only belch out gas, but aerosol droplets and ash are blasted into the stratosphere during major eruptions. If the major gas component of eruptions is carbon dioxide, that "evil" global warming gas, it will cause temps to increase globally. While on the other hand, if sulfur dioxide is the major component of an eruption it can lead to an over all global temperature drop. [pulling info from my brain from college courses]

        If volcanoes, globally, are belching out a massive amount of gas, it will eventually lead to a dramatic change in atmospheric conditions. The altered atmospheric conditions will then have the domino effect on global climate. Any dramatic fluctuation in climate obviously didn't occur over a short period of time, but would have affected the dinosaurs in the long run(droughts, famine or temperatures they were not able to adapt to) and, in short, lead to the Darwinian 'survival of the fittest'. The mammals were the ones that were able to adapt, so they 'took over'.
      • by wish bot (265150) on Friday November 02 2007, @03:26PM (#21217085)
        Unfortunately, Keller is about the only person who believes the date of the impact is 300,000 years earlier than the extinction. A lot of people have issues with the location and interpretation of the core samples she has taken to create this theory - directly from the impact site. To me, trying to analyse samples from the impact site of an explosion 2 million times more powerful than our largest nuclear bomb blast is a pretty insane thing to do - it'd be like trying to read the tea leaves in your cup of tea after someone ran a bulldozer through your house, set fire to the rubble, dug it up and sent it to the dump.
  • Obviously they've hunted land they can see, maybe look under the ice? Just recently greenland discovered a new island when some ice melted.
    • I think you'd have to go a long way down. I think Anywhere with ancient surface easily available would be OK. Mountains are more likely to be a good place, since deep ancient surfaces are uplifted.

      It's not so easy to find good sites though, Time is money, and there isn't much of either available usually. Most places where you can find good rock are out of the way, and many have only a few months of the year you can be there.
      • You'd think they'd be able to use some NASA technologies (xray, heat, whatever else they use to probe the cosmos) from space or something to see through the ice, then identify suspect patterns. Money for sure is an issue.
  • by Anonymous Coward
    But where's the crater? "I wish I knew

    Its gotta be in Oklahoma. Trust me, that place is a **** hole!
  • Xenu (Score:3, Funny)

    by jas_public (1049030) on Friday November 02 2007, @02:59PM (#21216655) Journal
    This sounds like an L. Ron Hubbard story.
  • I know the circumstances of the dinosaur's extinction are controversial, but this is what they tought me way back in elementary school...
  • by User 956 (568564) on Friday November 02 2007, @03:04PM (#21216709) Homepage
    The Deccan volcanism was a long cumulative process that released vast amounts of greenhouse gases into the atmosphere.

    Yeah, but with our advanced technology, we can cut that time in half.
  • Easy (Score:3, Funny)

    by rucs_hack (784150) on Friday November 02 2007, @03:06PM (#21216751)
    It shouldn't be that hard to work it out, after all, wasn't it only about ten thousand years ago it happened? /ducks :)
  • by gentlemen_loser (817960) on Friday November 02 2007, @03:09PM (#21216805) Homepage
    Everyone knows that the earth is only 6000 years old, as evidenced here [creationmuseum.org] They even have models of Eve with vegetarian Raptors. See. [arstechnica.com] I do not understand why anyone pays any attention to these activist scientists. Duh...
    • Vegatarian Raptors? Heh. Is that really an exhibit? I'd go see it, but I'd probably wet myself from laughing.

      What does a Raptor with six inch claws eat? Anything it wants.
    • Well... not according to Jesus.

      When you see your likeness, you are pleased. But when you see your images which came into existence before you, which neither die nor become manifest, how much you will have to bear!

      --Gospel of Thomas
    • Ha ha ha! Oh gosh that's funny! That's really funny! Do you write your own material? Do you? Because that is so fresh. "Everyone knows that the earth is only 6000 years old". You know, I've never heard anyone make that joke before. Hmm. You're the first. I've never heard anyone reference that on Slashdot before. Because that's what the religious people say in church right? Isn't it? "The earth is only 6000 years old". And, and yet you've taken that and used it out of context to insult people who are differe

      • by lgw (121541) on Friday November 02 2007, @05:48PM (#21218797) Journal
        Wait, wait, let me get this right. The "6000 years" thing is so obviously stupid that no one should accuse Christians of believing it, but the part where Christians believe that a cosmic Jewish zombie who was his own father can make you live forever if you symbolically eat his flesh and drink his blood and telepathically tell him you accept him as your master, so he can remove an evil force from your soul that is present in all humans because a woman made from a rib was convinced by a talking snake to eat from a magical tree and thereby pissing off an invisible wizard who lives in the sky -- that part -- is not obviously stupid at all, but obviously true?

        For simplicty, please list which fairy tales you do and don't believe in, so we can insult your *actual* beliefs?
        • Re:Ridiculous... (Score:4, Insightful)

          by Digital Vomit (891734) on Friday November 02 2007, @04:03PM (#21217575) Homepage Journal
          I don't think the earth is 6000 years old, either, but I'm sick to death of hearing this exact same joke repeated again and again and again every time something even remotely tied to the distant past is brought up on Slashdot. I guarantee we'll see the exact same joke told at least a half dozen times here.
          • Re:Ridiculous... (Score:5, Interesting)

            by gentlemen_loser (817960) on Friday November 02 2007, @05:38PM (#21218637) Homepage
            And I'll keep telling it, and others like it until the groups who subscribe to such theories STOP pushing it on everyone else (ala school boards calling evolution into question, government policy decisions being based on it, etc.). I believe that such policies are dangerous as they are pushing our educational system backwards, thereby potentially triggering a landslide of bad side effects (intolerance, war, and damage to the economy, to name a few). You'll notice that I have never, nor will I ever, make an Amish (or other such group) joke. I politely disagree with their position, but fully recognize and respect their right to practice those beliefs. Its when those beliefs start being rammed down my throat that I take issue...
  • Cause (Score:5, Interesting)

    by rossdee (243626) on Friday November 02 2007, @03:12PM (#21216855)
    Maybe the meteor impact caused the volcanos to start up.
    • There is a theory that this is what happened. The Siberian Traps were already going, they were a long term thing, but they had an upsurge of activity that was seriously bad for the environment at around the time the Asteroid hit, or so I recall, it was a while ago I learned this. Wait a bit and I'm sure a slashdotr technorati will provide the ref :)
    • Re: (Score:3, Informative)

      That's already been proposed. See the entry on the Shiva crater [wikipedia.org].
  • ...it must have been 7-8 degrees warmer..
    and a whole lot tighter, right?

    right?
  • by Joe the Lesser (533425) on Friday November 02 2007, @03:14PM (#21216867) Homepage Journal
    Fry: What killed off the dinosaurs?

    Giant Super Brain: Me!
  • How about a huge impact somewhere in the south Pacific west of Chili, this caused a shockwave rippling out from there around the world. The shockwave ripples then reconverged on the opposite side of the world in India, causing the Deccan Traps to go pop. I figured out the likely location using the wonderful Earth Sandwich tool http://www.zefrank.com/sandwich/tool.html [zefrank.com]
  • A crater all that big would be pretty obvious, i.e. Hudson Bay or possibly the general Yucatan shape. I vote for the Yucatan because maybe it followed the other rock in right behind it and hit harder, which is why the one famous crater is so hard to see land-wise. Maybe the 300,000 years is how long the iridium took to land back on earth from being jettisoned into our atmosphere and/or beyond. (gravity)
    • I vote for the shallow sea in between India and Asia (now the Himalayas). It might also explain why India was traveling so fast when it hit Asia.
      • Jokes aside search for "Shiva Crater". Just found it myself and it sounds like the crater you are looking for.
  • But where's the crater? "I wish I knew," says Keller."
     
    It's the entire Gulf of Mexico. I mean, it's obvious from the shape of the thing.
     
    Remember you read it here first.
    • can I join your fan club? My first thought was "Under the antartic cap of course" but I think the gulf is the best cosmo-conspiracy theory yet. (an no I am not being sarcastic)
  • by Fx.Dr (915071) on Friday November 02 2007, @03:24PM (#21217057)
    DUH! The Church of Scientology has been saying this for years now, people! Get with the times!
    • DUH! The Church of Scientology has been saying this for years now, people! Get with the times!
        (Score:-1, Troll)

      All right who gave mod points to a bivalve?
      (And yes I am sure everyone else would have found that funny.)
    • DUH! The Church of Scientology has been saying this for years now, people! Get with the times!
       
      Parent is FUNNY via witty sarcasm and reasonably on topic not TROLL.
       
      OK, not 5 but at least 2 or 3.
  • Massive-ass Earth Farts, and Ka-Phooey! That's all it took?
  • The idea that absolute dating techniques can survive catastrophic events without the introduction of abnormalities is rather presumptive. Just last week, there was an announcement that uranium isotopes are not invariant ...

    http://http//www.sciencedaily.com/releases/2007/10/071023103947.htm [http]

    What is the cause of the extraneous decay?

    One Russian researcher has performed a simple experiment that demonstrates a statistical enigma within decay rates that mysteriously correlates with movements of the stars, the Su
    • by zerocool^ (112121) on Friday November 02 2007, @04:12PM (#21217681) Homepage Journal

      For starters, the 21st Century Science and Technology [wikipedia.org] is NOT a reputable, peer-reviewed scientific journal. It is a group of quacks. Literally, the magazine (which is not even printed anymore, copies are available now as pdf only) is a thinktank of scientists who challenge "the assumptions of modern scientific dogma, including quantum mechanics, relativity theory, biological reductionism, and the formalization and separation of mathematics from physics." (from their statement of purpose).

      Furthermore, the "21st century" publication follows the line of groupthink known as the LaRouche Movement [wikipedia.org], a wacky pseudo-political group of conspiracy theorists and nutcases. Their group spews fascist, anti-semetic ideology like it's going out of style.

      That alone makes your bullshit transparent, but you state that you want something other than attacks on credentials (I happen to believe that scientists stand or fall on their credentials, including past bodies of work, but whatever). So, in a nutshell, Radiometric Dating [wikipedia.org], including Carbon-14 dating and other methods such as Rubidium-strontium dating and Uranium-lead dating, is EXTREMELY accurate and accepted by all reputable scientists and peer-reviewed scientific journals.

      So, if your russian scientist is the only one shouting that it's inaccurate, we must be left asking "Why does every other scientist accept it, and what is his axe to grind?".

      ~Wx
  • I do not care much for lizards. They are big, stupid and slow, and they smell. All these dinosaurs are around, and I hated them all, but there's all sorts of stupid regulations about dinosaurs, thanks to Al Gore leading the save the dinosaur charge.

    So I hopped into my time machine, gathered up some of the world's famous hunters, went back in time and killed the dinosaurs. Me and Buffalo Bill must have slaughtered 1,200 T-Rex's in what is now Montana, just in one night of drinking and hooting and hollering and a-shooting.

    Those of you wonder what really happened to Jesse James, though, should know that he really did die 65 million years ago. We were playing cards one night after a big hunt and I drew a royal flush to his full house. Jesse probably wouldn't blown my head off in anger, but Buffalo Bill was quicker on the draw and he said, "Don't even do it Jesse." Jesse stuffed his revolver back into his holster, grabbed the bottle and went off in a huff. But as he was a stompin' away, he was set on by a pack of raptors and chewed up. It was a sad thing, but T.R. was able to go shoot two down with that pistol of his, and, thus, while we couldn't save Jesse, we at least saved the bottle of whiskey.

    I reckon it took us a few months to kill all them dinosaurs. Since they all ate the biggest dinosaurs, we just took out all the brontos and crushed their eggs, and the rest all starved. We shot a bunch too. And then I dropped everyone back into their own times, and came back to this one, and there was not a dinosaur to be found.

    Thank god!

    So I called upon Mr. Gore to see if he remembered how much he liked dinosaurs in this adjusted timeline, and he said that he thought dinosaurs were ok in their own time, and said that, if we didn't do something about global warming, dinosaurs might come back.

    So now, I gotta back in time and gather up the boys and go visit henry ford.

    Ah, the work that we do!
  • Keller's far-out (Score:3, Informative)

    by yusing (216625) on Friday November 02 2007, @09:08PM (#21220565) Journal
    The 300,000 year hypothesis isn't widely supported.

    "Many scientists reject Keller's analysis, some arguing that the 10 meter (32.8 ft) layer on top of the impact spherules should be attributed to tsunami activity resulting from impact. Few researchers support Keller's dating of the impact crater." -- Wikipedia ... http://en.wikipedia.org/wiki/K [wikipedia.org]-T_boundary