Posted on 01/02/2009 7:44:26 AM PST by Red Badger
First an explosion as powerful as thousands of megatons of TNT rained meteorites down on North America. Then forest fires broke out across the continent, sending up a thick layer of soot and dust that blocked out the sun. A sudden ice age ensued, and some of the Earth's largest animals went extinct in a blink of geological time.
It's well known that a meteorite colliding with Earth is considered the most likely reason dinosaurs died off 65 million years ago. Now a team of scientists says it has found new evidence that a comet triggered a similar extinction much more recently: just 13,000 years ago, when humans were around to witness the event and suffer its terrible consequences.
The researchers also think that when the comet exploded above the planet's surface - ultimately killing off mammoths, saber-toothed tigers and other large mammals that roamed North America - Chicago wasn't too far from ground zero.
"If you'd been in Chicago back in that time, it would've been one very bad day," said Allen West, an Arizona geophysicist and one of the authors of a paper appearing Friday in the journal Science.
The scientists, led by University of Oregon anthropologist Douglas Kennett, say their report offers up a "smoking bullet" - proof it was a comet that set off the sudden, thousand-year freeze and wiped out the big animals of the era.
Working at multiple sites across the continent, researchers found nanodiamonds - microscopic particles thought to be found on comets - in a 13,000-year-old layer of rich sedimentary soil called a "black mat." Beneath the layer with the nanodiamonds, fossils of the animals are abundant. After that layer, they disappear, West said.
"It's extraordinary that tens of millions of animals disappeared synchronously at exactly the time when the diamonds and carbon layer are laid down across the continent," said West, whose co-authors include DePaul University chemist Wendy Wolbach.
Arrowheads and other artifacts from the Clovis culture of humans - an early hunter-gatherer society - also vanish after the black mat was laid down 13,000 years ago.
In 2007, West and a team of scientists published an analysis of black mats from several regions that found heavy metals, soot and charcoal suggestive of meteorite impacts and subsequent fires. The new report says the discovery of nanodiamonds in the same material is more evidence of a cosmic strike.
Archeologists have long speculated about whether climate change or over-hunting drove the mammoths, tigers and other "megafauna" to extinction and led to the decline of the Clovis culture.
Many remain skeptical of the comet theory and think there may be better explanations for what happened, said Daniel Amick, an associate professor of anthropology at Loyola University who studies the Clovis culture.
"When most archeologists heard about it they were somewhat dismissive," Amick said. "We would think, 'How in the world could we have missed this? How could this spectacular kind of event have occurred and never even dawned on us?'"
The authors have much to prove before their theory is accepted, Amick said, like pinpointing the date of the event and ruling out other potential causes of extinction and climate change.
In response to one common criticism of the comet theory - that no craters have been found from an impact - West said the comet may not have actually reached Earth, but exploded into fragments somewhere above the surface.
Where exactly that might have happened is a mystery, but high concentrations of nanodiamonds at a site in Eastern Michigan suggest the Great Lakes as a possibility.
"We think that Chicago might well have been very near ground zero," West said.
The idea that a comet may have caused catastrophic climate change and extinction relatively recently in Earth's long history suggests scientists shouldn't dismiss the possibility of it happening again, Wolbach said.
"Should we be doing more to try to deflect future asteroids, or is that too sci-fi?" she said. "If this is true and there was an impact 12.9 thousand years ago, obviously this is not something that's just a theoretical idea, it's a real thing."
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Ping!..........
Plus it's amazing how Alligators are always near ground zero for these Asteroid/Comet hits, yet they always manage to survive unscathed.
This IS the flood of Noah. Read Velikovsky seminal trilogy: Worlds In Collision, Earth in Upheaval and Ages in Chaos. Then: Ignatius Donneley- Ragnarok, and Vine Deloria- Red Earth, White Lies. This event is recorded in the myths of ancient people the world over. www.kronia.com.
It's Bush's fault. Bush and those damned SUVs.
Women and minorities hardest hit.
Yeah, a big fireball and a flaming hole in the ground the size of Texas would tend to do that.....
Ping!............
I for one am getting a bit tired of “scientists say”. Lets face it, Al Gore says we have global warming and is backed up by “scientists” and I am still shoveling Gore’s global warming in the form of the heaviest snowfall for many years.
Old honest Al is making a monetary killing on the ignorant citizens of the world.
I was raised not far from there.....8^)
oops! Wrong end of state!.....
Comet.
It will make your teeth turn green.
Comet.
It tastes like gasoline.
Comet.
It will make you vomit.
So try some Comet and vomit today.
Not a hole in the ground per se, but a mile thick sheet of ice gone in a big hurry - all that water vapor would have caused a huge global warm-up.
A comet that wipes out all the big mammals but one, humans?
Of course.
“The idea that a comet may have caused catastrophic climate change and extinction relatively recently in Earth’s long history suggests scientists shouldn’t dismiss the possibility of it happening again, Wolbach said.”
The History Channel has it covered.....over and overandover....
And all the huge forest fires..........
Humans were fairly well spread out across the globe, so it would not have killed off all of us...............
Mexico gets it 65 mil years ago, Chicago gets it 13k years ago... Geez, God has the New World in his crosshairs! Why us??
That’s too small a Comet, you’d need at least a four-door with a V-8!
If it doesn't grab a headline, confirm a pre-established political bias, or have some global implication, it doesn't get funded.
Private industry funded science only gets exposure when a company is seeking investors, particularly in the pharmaceutical industry.
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