Posted on 06/02/2006 11:44:43 AM PDT by cogitator
An apparent crater as big as Ohio has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago.
The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs.
The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward, the researchers said.
"This Wilkes Land impact is much bigger than the impact that killed the dinosaurs, and probably would have caused catastrophic damage at the time," said Ralph von Frese, a professor of geological sciences at Ohio State University.
How they found it
The crater is about 300 miles wide. It was found by looking at differences in density that show up in gravity measurements taken with NASA's GRACE satellites. Researchers spotted a mass concentration, which they call a mascon—dense stuff that welled up from the mantle, likely in an impact.
"If I saw this same mascon signal on the Moon, I'd expect to see a crater around it," Frese said. (The Moon, with no atmosphere, retains a record of ancient impacts in the visible craters there.)
So Frese and colleagues overlaid data from airborne radar images that showed a 300-mile wide sub-surface, circular ridge. The mascon fit neatly inside the circle.
"And when we looked at the ice-probing airborne radar, there it was," he said today.
Smoking gun?
The Permian-Triassic extinction, as it is known, wiped out most life on land and in the oceans. Researchers have long suspected a space rock might have been involved. Some scientists have blamed volcanic activity or other culprits.
The die-off set up conditions that eventually allowed dinosaurs to rule the planet.
The newfound crater is more than twice the size of the Chicxulub crater in the Yucatan peninsula, which marks the impact that may have ultimately killed the dinosaurs 65 million years ago. The Chicxulub space rock is thought to have been 6 miles wide, while the Wilkes Land meteor could have been up to 30 miles wide, the researchers said.
Confirmation needed
Postdoctoral researcher Laramie Potts assisted in the discovery.
The work was financed by NASA and the National Science Foundation. The discovery, announced today, was initially presented in a poster paper at the recent American Geophysical Union Joint Assembly meeting in Baltimore.
The researchers say further work is needed to confirm the finding. One way to do that would be to go there and collect rock from the crater to see if its structure matches what would be expected from such a colossal impact.
Gosh-a-roony! How can I go on in the face of such ironclad logic, supported with so much evidence?
Kimberlite pipes!
My new favorite thread.
Is there any evidence of huge craters in diamond-producing regions? It would make a certain amount of sense.
What happened to the Gulf of Mexico?
I thought that was the crater of the rock that caused the extinctions?
Most of us know that it was the flood that did it, and this stuff is for the denial club.
Your idea of 'observables' appears to be very much related to the consumption of large quantities of adult beverages.
This is a science thread?
Next thing you're going to tell us is that you're a scientist, huh? Give us a good laugh, spam man!!!
The latter for sure. First you're going to have to show Iche what science is, since he is one of the other kind. His definition of scientist is anybody that has been baptised in the church of evo-loosion.
Say this a thousand times: Ichenoumon is a syintist, Ichenoumon is a syintist, Ichenoumon is a syintist, Ichenoumon is a syintist, Ichenoumon is a syintist, Ichenoumon is a syintist, Ichenoumon is a syintist....
Say it enough and it can become true,and it helps if you know what code to set your captain midnight ring to.
Still, though the observation runs counter to the expectation of the Big Bang ("BB") premise, they tell us the reason Venus spins in its orbit opposite to its nearest neighbors Earth and Mercury is because a meteor supposedly knocked it off its rotation also without disrupting its orbit. Add to that, Uranus has a rotation counterintuitive to the BB premise and they use the same stupid explantion for that, as well!
Materialists believe in miracles, and worship at the alter of Fortune and Chance even as the pagan Romans did. They just don't want to believe in the Creator God, Himself, because they fear He might expect something of them that their false little goddess of Fortune togther with their perpetually shrinking intellects won't.
Can you imagine a meteor big enough to affect Uranus? It would have to have been bigger than the earth .
Do you really think so?
The image the UN didn't want you to see...
If you really think that the great Bible scholars have failed to adequately expound upon the pertinant realities of our time I do. Perhaps you were just availing yourself of an opportunity for sarcasm; I do that on occasion too.
Oklahoma has winds that can blow away your house!
;-D
It's right where we left it.
I thought that was the crater of the rock that caused the extinctions?
As if often the case, you thought wrongly.
Most of us know that it was the flood that did it, and this stuff is for the denial club.
Uh huh. Sure. You betcha.
"This is your brain on anti-evolutionism"...
As anyone with a gradeschool education would have realized, the thousands of craters on the Moon indicate quite obviously that this region of the Solar System has been subject to quite a few significant impact events over the past few billion years, and thus your bizarre derision over the fact that the Earth has been hit by at least two large meteors in the past few hundred million years is sadly misplaced.
And this was big enough of an event to allegedly cause mass global exitinction, yet the Earth was also somehow not affected in what is it's uniquely favorable orbital path, which sustains life in the first place?
Yes, because you are apparently grossly ignorant of the many orders of magnitude difference between the size of an impact which can seriously screw up living conditions on Earth, compared to the vastly larger size of one that would be necessary to affect "it's [sic] uniquely favorable orbital path". I'd end this by suggesting that you "do the math", but clearly, that would be asking something beyond your abilities.
Still, though the observation runs counter to the expectation of the Big Bang ("BB") premise, they tell us the reason Venus spins in its orbit opposite to its nearest neighbors Earth and Mercury is because a meteor supposedly knocked it off its rotation also without disrupting its orbit.
Actually, no, Venus most likely rotates in a retrograde manner due to tidal locks with the other planets.
As for Uranus, it is far more likely due to a large impact early in its history, but while that would "knock it off its rotation" as you clumsily say, you're incorrect when you say that anyone has claimed that it would do so "without disrupting its orbit" -- it would, actually, and almost certainly has. You really need to read more science journals and fewer creationist pamphlets.
Add to that, Uranus has a rotation counterintuitive to the BB premise and they use the same stupid explantion for that, as well!
No, they use a different and "non-stupid" explantion [sic]" for that because that's what the evidence indicates.
Speaking of "stupid explantions [sic]", I'll send you $1000 if you can explain why exactly you think the Big Bang is somehow incompatible with retrograde rotation of planets without making a complete fool of yourself (i.e., saying something really idiotic that demonstrates a gross ignorance of even the most basic high school science). Go for it!
Materialists believe in miracles, and worship at the alter of Fortune and Chance even as the pagan Romans did. They just don't want to believe in the Creator God, Himself, because they fear He might expect something of them that their false little goddess of Fortune togther with their perpetually shrinking intellects won't.
Uh huh. Sure. Again, you might want to try reading more science journals and fewer Jack Chick tracts and so on.
Looks like it slipped right through the ozone hole. Damn Bush and his SUVs and global warming.
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