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Earth Australia

Giant Impact Crater Found In Australia 109

Posted by timothy from the convict-labor-can-fill-it-back-in dept.
An anonymous reader writes "One of the largest meteorite impacts in the world has been discovered in the South Australian outback by geothermal researchers. It may explain one of the many extinction events in the past 600 million years, and may contain rare and exotic minerals. The crater is said to have been 'produced by an asteroid six to 12 km across' — which is really big!"
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Giant Impact Crater Found In Australia More

Giant Impact Crater Found In Australia

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  • But how much energy is that? (Score:3, Interesting)

    by Zaphodox ( 1751752 ) on Wednesday October 27, 2010 @05:08AM (#34035422)
    Okay so they give widely varying estimates of the crater's size - assuming the centre value of 120 Km a +/- 60 Km ia one hell of a margin of error. I imagine that the energy released from such an impact is orders of magnitude greater than any nuke we could ever throw at each other. The article metions the release of CO2, but i thought that by definition asteroids were just lumps of rock. So where does the CO2 come from after the impact?

    • Re:But how much energy is that? (Score:4, Interesting)

      by Trogre ( 513942 ) on Wednesday October 27, 2010 @05:20AM (#34035468) Homepage

      I would guess the ground. When a meteor hits land, a lot of the ejected material is from the ground, not the meteor itself. Rocks apparently have a lot of oxygen and carbon locked up in them.

    • Re: (Score:3, Informative)

      by rve ( 4436 )

      Maybe it crashed into a limestone formation? Limestone (and other carbonate rock like marble and karst) are basically giant lumps of CO2.

      • Re: (Score:2, Informative)

        by bigrockpeltr ( 1752472 )
        jsut to correct your (minor) mistake, karst is not a type of rock, it is a type of topography used to refer to geological features made from (usually eroded) carbonate rock and include caves (including stalactites, stalagmites and other cave formations), aquiefers, dolines, sinkholes etc. Cockpit country in Jamaica is a good example of karst topography

    • Re: (Score:2)

      by rossdee ( 243626 )

      The earths crust contains carbon, and this impact would have vaporized a lot of that. Also there would be molten bits of rock flung over the whole planet, causing a global firestorm from whatever vegetation was around at the time.

    • Re: (Score:2)

      by khallow ( 566160 )
      Depends on what it hits. If it hits a bed of limestone, that could release a lot of CO2. That's supposed to have happened at Chicxulub (the impact on Mexico's Yucatan peninsula) which is thought to be at least a contributor to the extinction of the dinosaurs). Also 300 million years ago, there would have been a lot of forest to burn.

    • Re: (Score:3, Informative)

      by careysub ( 976506 )

      Okay so they give widely varying estimates of the crater's size - assuming the centre value of 120 Km a +/- 60 Km ia one hell of a margin of error. I imagine that the energy released from such an impact is orders of magnitude greater than any nuke we could ever throw at each other. The article metions the release of CO2, but i thought that by definition asteroids were just lumps of rock. So where does the CO2 come from after the impact?

      It is about 100,000 megatons, at its peak the world nuclear arsenal had around 20,000 megatons.

      CO2 is released if the asteroid impacts a carbonate rock bed - it then releases the CO2 just like a giant cement kiln (which is a major source of human CO2 release BTW - about 5% of the global release).

  • Where? (Score:5, Informative)

    by DeathToBill ( 601486 ) on Wednesday October 27, 2010 @05:22AM (#34035472) Journal

    TFA doesn't mention a location. There is a roughly circular sort of feature in about the right place and about the right size centred here:

    http://maps.google.com.au/?ie=UTF8&ll=-28.614665,141.139984&spn=0.806518,1.234589&t=h&z=10 [google.com.au]

    You can see it better if you zoom out a couple of steps. It's not very well defined, and may just be wishful thinking on my part!

  • In case someone has some spare time to look for the crater on Google Maps: map link [google.com] Cooper Basin [hydrocarbo...nology.com]
  • Seriously, a 80-160 km crater is not giant. Big, okay, they don't form every day, but there are much bigger craters than that. Like Menrva on Titan.

    • It doesn't have to be the biggest crater. Just big enough. An impact of that magnitude would have major catastrophic effects on the whole planet.

      And, for what it's worth, I think pretty much the entire northern hemisphere of Mars wins any "I've seen bigger" contest. Link [nature.com] (and a PDF link [diggernet.net] for those without Nature access)

    • Re: (Score:1, Interesting)

      by Anonymous Coward

      I've always wondered what damage we'd see if an asteroid that size is dropped from a height of 1km. Would there be devastation (apart from those directly in the firing line)?

      • Re: (Score:3, Informative)

        by GameboyRMH ( 1153867 )

        As a quick guess I'd say the destruction would be limited to a relatively small area of the planet. You'd have total devastation within a radius of maybe a few hundred kilometers, but the rest of the planet would be fine. You wouldn't have ash encircling the planet and blocking out the sun as with a Chicxulub-type impact (which is by far the most devastating effect of a large asteroid impact to life on a planet), although you may still get some smaller Eyjafjallajokull-size ash clouds.

        Now if it landed in th

        • Re: (Score:2, Interesting)

          by dachshund ( 300733 )

          You wouldn't have ash encircling the planet and blocking out the sun as with a Chicxulub-type impact (which is by far the most devastating effect of a large asteroid impact to life on a planet), although you may still get some smaller Eyjafjallajokull-size ash clouds. Now if it landed in the ocean you'd have serious mega-tsunamis that would wipe out of a lot of coastal areas all around the world, but again not devastating on a planetary scale.

          Well, don't take it as fact, but the geologist who discovered t

      • Re: (Score:2)

        by khallow ( 566160 )
        You're talking about an energy that is many orders of magnitude lower. Maximum velocity before the rock hits ground or ocean is about 150 m/s. In comparison, asteroids from space would be coming in at around 35 km/s. That's more than three orders of magnitude faster. The energy released by the collision would be the square of velocity times mass, so you're looking at least at six orders of magnitude more energy released in a real asteroid collision than in a "oops, we dropped it!" impact.
      • we could lay you down, and fire a bullet at your head from about a 1000 meters up. or we could drop the bullet on your head from a distance of 10 meters. one will hurt. the other, you won't feel a thing...

    • Re: (Score:3, Funny)

      by Rogerborg ( 306625 )

      Seriously, a 80-160 km crater is not giant. Big, okay, they don't form every day, but there are much bigger craters than that. Like Menrva on Titan.

      Oh, sure, sure, but you really had to hike there before all the tourists discovered it and ruined the local culture.

    • Re: (Score:3, Insightful)

      by gstoddart ( 321705 )

      Seriously, a 80-160 km crater is not giant. Big, okay, they don't form every day, but there are much bigger craters than that. Like Menrva on Titan.

      Nobody is saying this is the biggest crater ever created in the solar system.

      But, they are saying that anything which creates a crater of that size on Earth is going to make one hell of a mess. From TFA:

      "Nothing within a few hundred kilometres of the blast would have survived, but more importantly the climate of the entire Earth would have been changed. It woul

    • Sorry, this was a bit of an inside joke. I am a planetary geologist, so yes, it is pretty interesting when we can add another large impact basin to the ones we can study right here on Earth.

      The joke comes from the first time I went on a field trip to Meteor Crater east of Flagstaff, Arizona. Because I've done some work on the eroded impact craters of Titan, all I said was "Meh, I've seen bigger" because all the crater on Titan are bigger than the mile-wide Barringer crater.

  • This makes you wonder how many possible asteroid impacts happened in the Ocean.

    • Some people reckon the entire Pacific Ocean basic and the moon were a result of asteroid impact.. the moon is actually a bunch of material ejected from the earth when the asteroid(s) hit.

      • Not an asteroid. A Mars sized planetoid.
      • No, it's clearly a doomsday planet that was stopped in it's tracks by the fifth element.

      • Some people reckon the entire Pacific Ocean basic and the moon were a result of asteroid impact

        Many, many years ago, that idea was proposed on some extremely tenuous grounds. There's a faint bell tinkling in my head that it was actually one of Darwin's sons, and the timing is vaguely right for it to have been a response to discovering the high average depth of the Pacific from the Challenger expedition. The idea has never had any strong support from data, and since the turn of the last century (i.e. 1900) it has been a pretty dead idea.

        the moon is actually a bunch of material ejected from the earth when the asteroid(s) hit.

        That is a gross oversimplification and distortion of the modern

    • Re: (Score:2)

      by Mashiki ( 184564 )

      Probably a lot. Canada has 12 confirmed 20km+ impacts craters including the second largest in the world(250km). And even with the amount of land you're talking about here, there's probably another 4 to 8 dozen that haven't been discovered that are easy to identify. And probably another 10-30 dozen on top of that, which are only faint after the last glaciation period.

  • Obligatory (Score:4, Funny)

    by antifoidulus ( 807088 ) on Wednesday October 27, 2010 @05:36AM (#34035512) Homepage Journal
    "You call that a meteorite? THIS is a meteorite!"

  • Obviously... (Score:3)

    by jhesse ( 138516 ) on Wednesday October 27, 2010 @05:44AM (#34035534) Homepage

    This must be where The Lost City of Pnakotus [wikipedia.org] was located!

  • Are they sure the crater is that old? I just read something about a problem with nuclear warheads.

  • Original Source (Score:3, Informative)

    by martyb ( 196687 ) on Wednesday October 27, 2010 @06:54AM (#34035698)

    There's an article [uq.edu.au] on the University of Queensland's web site (where the researchers hail from).

    The land surface that the asteroid hit is now buried under layers of sedimentary rock and Dr Uysal thinks the original crater most likely eroded away.

    "Dr Uysal and Dr Glikson will present their findings at the Australian Geothermal Energy Conference in Adelaide, 16-19 November 2010."

    To read more about their research, see their conference paper (pdf). [uq.edu.au] (This may not be specifically on the impact, but on their geothermal research, instead.)

    In short, not the biggest, oldest, newest, or any other superlative. Still, given the estimated size of the impact, I'd expect it to have had a major impact on the Earth's weather for quite a while.

  • they're not even in the periodic table!

  • On TV you see lots of computer sims but none look realistic to me. Would there be a light covering the sky so bright you couldn't see it or would it traverse the atmosphere so quick it wouldn't have time to heat up and you really would see this huge space rock impact. And what would the explosion look like? WOuld it be a fireball initially or would you simply see billions of tons or rock being launched into orbit?

    • Re: (Score:1)

      by pi865 ( 1434123 )
      Can't find the link, but read a 'more rigorous' prediction which mentioned a) pre-impact toasting of the planet, and b) immense pre-impact winds that would toss anyone and anything so high into the air they'd be dead on return. The article included distances though and might have been based on a hypothetical 10km body. Doesn't seem likely that most people would witness impact in a true extinction event, an absolute version of which seems more and more impossible/unlikely the more one learns about both rea
    • It should go faster than a smaller meteorite would because air resistance would have less decelerating effect (air resistance goes with the square of the size, mass with the cube so acceleration goes with 1/size), but the increased air resistance would mean more heating, which would be in proportion to the increased surface area (both go with the square of the size). Overall, I reckon it would light up like any other meteorite.

    • Re:What would an impact look like? (Score:5, Interesting)

      by careysub ( 976506 ) on Wednesday October 27, 2010 @09:26AM (#34036502)

      On TV you see lots of computer sims but none look realistic to me. Would there be a light covering the sky so bright you couldn't see it or would it traverse the atmosphere so quick it wouldn't have time to heat up and you really would see this huge space rock impact. And what would the explosion look like? WOuld it be a fireball initially or would you simply see billions of tons or rock being launched into orbit?

      A very useful source of information is the Asteroid Impact Effects on-line program: http://impact.ese.ic.ac.uk/ImpactEffects/ [ic.ac.uk]

      Taking their upper size estimate (12 km) and average impact parameters (17 km/sec, 45 degree angle of entry) this would light up brilliantly at around 120 km altitude and get brighter all the way down its 10 second transit to the Earth. However you would probably not want to be anywhere you could actually see its entry. At a distance of 1250 km you would just see it light up on entry on the horizon, and thereafter the glow would be indirect until impact. THEN - part of the fireball which appear ~5 times larger and brighter than the Sun would rise above the horizon and irradiate you for about half an hour. This would be quite uncomfortable - a first degree thermal burn would develop after several seconds, but you get roasted for a hundred times longer than that, or until the fine ejecta thrown into space comes down and starts blocking your light after 10 minutes of so. And an hour after the impact a 12 psi blast wave with tornado-speed 335 mph winds would hit. This would likely be fatal.

    • On TV you see lots of computer sims but none look realistic to me.

      This is only of academic interest.

      Would there be a light covering the sky so bright you couldn't see it or would it traverse the atmosphere so quick it wouldn't have time to heat up and you really would see this huge space rock impact. And what would the explosion look like? WOuld it be a fireball initially or would you simply see billions of tons or rock being launched into orbit?

      If you're observing the touchdown of a multiple-kilometre body (asteroid, banana, comet, dog ; it doesn't matter) on the Earth, from the Earth's surface, and you see the fireball, then you're dead to a close approximation in position and within a couple of hours precision in time. Geologically, these are unimportantly small differences, though they might make some personal difference to you, for a short time.

      If you're observing from near-Earth orbit when you see the fireba

  • Maybe the impact crater is just the final resting place of Paul Hogan's acting career. Carbon dating would probably reveal around 2001.
  • Chicxulub crater from the eastern tip of Mexico is totally infuriated and angry by this news.
    Chicxulub states "I am the ORIGINAL extinction crater, and DON'T YOU FORGET IT!" [wikipedia.org]

    • Re: (Score:2)

      by Mashiki ( 184564 )

      The impact crater in Sudbury [wikipedia.org] is not amused at your piddly size.

      • ... nor your pathetically recent age. (Sudbury could quite reasonably have been responsible for the extinction of half the species of life on the Earth at the time, given that species diversity seems to have been less in those times.)
  • Every time I see the map, it seems like if you follow the western perimeter of lake michigan around to the entry to the georgian bay and down the east side of lake huron, through London Ontario, and the southeast.... This is known to be a rock ridge, but it sure looks like a giant circle to me. They say its' from the glacier, but it sure looks round :-)
  • Maybe it's where the beer atom was split?
  • croikey! that'd been won helluvah barbie!

  • Not uncommon (Score:3, Interesting)

    by confused one ( 671304 ) on Wednesday October 27, 2010 @09:28AM (#34036522)
    For what it's worth, these craters are probably not as uncommon as people think. I'm sitting inside one [wikipedia.org] right now.

    • Re: (Score:2, Interesting)

      by Push Latency ( 930039 )
      I've always wondered if the odd, round-shaped area in the "Northeast Kingdom" of Vermont was one, though I've never mentioned it to anyone until now. I used to wallpaper my room with topographic and relief maps as a kid, and that has always rather stuck out whenever I look at a relief map of VT.

      http://www.vermont-map.org/vermont.jpg [vermont-map.org]

    • Re: (Score:2)

      by sootman ( 158191 )

      "sitting inside one"--nice. Reminds me of one of my favorite jokes:

      As a Delta Air Lines jet was flying over Arizona on a clear day, the copilot was providing his passengers with a running commentary about landmarks over the PA system.

      "Coming up on the right, you can see the Meteor Crater, which is a major tourist attraction in northern Arizona. It was formed when a lump of nickel and iron, roughly 150 feet in diameter and weighing 300,000 tons struck the earth at about 40,000 miles an hour, scattering white

  • ...if The Creation Museum [wikipedia.org] has an exhibit on this yet?

    • ...if The Creation Museum [wikipedia.org] has an exhibit on this yet?

      Are they interested in things that weren't mentioned in Ussher? "If it's not in Ussher, it's too recent for us" being their philosophy. So they're welcome to everything else that does get mentioned in Ussher's work, without of course the benefits of modern science to alleviate them.

  • > The impact would have been impressive, producing "catastrophic effects - including a fireball, major earthquakes,
    > atmospheric clouding, CO2 release, tsunami effects, [and] the extinction of species"

    Thank GOD the world's only six-thousand years old. Just imagine!.... :-P

  • Only 76 comments... this story must be not having much of... an impact!

    YEAAAAAAAAAAAAAAAAAAAAAAAAH!
  • I hope it left an unknown element. We could call it Australium.

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