The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine in
the History of Civilization
by Richard Firestone,
Allen West,
Simon Warwick-Smith
Posted on 05/21/2007 10:16:48 PM PDT by TigerLikesRooster
Catastrophic Comet Chilled and Killed Ice Age Beasts
Jeanna Bryner
LiveScience Staff Writer
LiveScience.com
Mon May 21, 9:30 AM ET
An extraterrestrial object with a three-mile girth might have exploded over southern Canada nearly 13,000 years ago, wiping out an ancient Stone Age culture as well as megafauna like mastodons and mammoths.
The blast could be to blame for a major cold spell called the Younger Dryas that occurred at the end of the Pleistocene Epoch, a period of time spanning from about 1.8 million years ago to 11,500 years ago.
Research, presented today at a meeting of the American Geophysical Union (AGU) in Acapulco, Mexico, could shed light on major questions about the megafauna extinction, the disappearance of the Clovis people, and an abrupt climate change.
“Based on the distribution of material, it looks like this impact probably occurred in southern Canada near the Great Lakes, over what at that time would have been a major glacier, the Laurentide ice sheet,” said one of the presenters, Richard Firestone of Lawrence Berkeley National Laboratory.
Comet chemistry
They couldn’t find a distinct crater, suggesting the comet burst in the air rather than slamming into Earth. Even an airburst should leave its mark, so the scientists think the Laurentide Ice Sheet absorbed much of the impact.
A much smaller object burst in the air over Siberia in 1908, flattening 800 square miles of forest
Firestone and his colleagues investigated buried carbon-rich layers dating back 12,900 years and blanketing more than 50 areas that span from California through Canada and into Belgium. They found a slew of extraterrestrial markers, including nanodiamonds, which are formed by energetic explosions in space, elevated amounts of the rare element iridium and tiny capsules of glass-like carbon.
“Glass-like carbon is essentially carbon that’s been melted at very high temperatures,” like those from a comet impact, Firestone explained. They also found elevated levels of the rare Earth element iridium that are too high to be from Earth.
Mega die-off
During the last catastrophic animal extinction, more than three-fourths of the large Ice Age animals, including woolly mammoths, mastodons, saber-toothed tigers and giant bears, died out. Scientists have debated for years over the cause of the extinction, with both of the major hypotheses—human overhunting and climate change—insufficient to account for the mega die-off.
An extraterrestrial explosion could have triggered a wave of massive wildfires that reduced to ashes the mastodons of the day, say the scientists. At one site called Murray Springs in Arizona, a well-known Clovis site, the scientists found megafauna covered by the comet debris.
“This black mat drapes over the bones of partially butchered mammoths as if somebody was in the process of working on these animals while they were actually killed,” Firestone told LiveScience in a telephone interview. “And between this black mat and the bones of this mammoth we find this ejecta layer. So it’s as if the [impact] event occurred right on top of these mammoth bones and then this black mat occurs on top of that.”
Once put out, the fires would have left a barren landscape devoid of food for any remaining animals.
“I would argue that most of the megafauna either died or starved after this thing,” Firestone said. “But certainly there must’ve been pockets of survival of large animals even mammoths that may have survived for thousands of years beyond that, ultimately to be hunted to death or whatever happened to them.”
Chill out
The comet theory could also explain the abrupt plunge in temperatures during the Younger Dryas period. Presenters at this AGU symposium argue that the comet impact or explosion would have heated up the area, causing the Laurentide Ice Sheet to melt and send massive amounts of water into the Atlantic Ocean. The input would affect ocean currents, which are responsible for keeping the atmosphere at livable temperatures.
Plus, the massive wildfires would have loaded the atmosphere with Sun-blocking dust, soot, water vapor and nitric oxides. The result would be the abrupt climate cooling.
The evidence for a comet impact is substantial.
“I think the fact that there’s an impact is pretty definite. There are too many markers there for it all to be coincidence or happenstance explanations,” Firestone said, adding, “What will be debated is whether the extent of the impact was sufficient for instance to kill all of the megafauna or whether other factors were also equally important.”
New Recipe: How to Make a Mass Extinction Top 10 Surprising Results of Global Warming Images: Glaciers Before and After Original Story: Catastrophic Comet Chilled and Killed Ice Age Beasts
What kind of relish? Pickle?
I'll bet a nice slab of cheese and onion slice and sesame seed bun would have helped!
Only small things can heat up sufficiently in the atmosphere to do this.
A much smaller object burst in the air over Siberia in 1908...
Maybe Plato was right about Atlanteans' civilization's being the forerunner of the Egyptians'--Atlantis sunk by tsunamis splashed by the comet--and all but wiped out by the comet catastrophe!
And maybe there's more to this Phaeton myth than we realized!
I tell you...!
All right, Everybody! Just remember: You read it first here or FreeRepublic!
I take it you have a problem with people who formulate theories based on existing evidence but don’t state them as absolute fact.
Do you, then, support the notion that people should look at evidence and immediately (and arrogantly) claim that they have all of the answers? That doesn’t seem to leave any room for refining the theory based on new evidence, and that would be bad science.
Did comet start deadly cold snap?
Canada.com | Monday, May 14, 2007 | Margaret Munro
Posted on 05/16/2007 6:00:33 PM EDT by Mike Darancette
http://www.freerepublic.com/focus/f-news/1834769/posts
Diamonds tell tale of comet that killed off the cavemen
Guardian | 5-20-07 | Robin McKie
Posted on 05/20/2007 7:50:33 PM EDT by Renfield
http://www.freerepublic.com/focus/f-news/1836898/posts
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine in
the History of Civilization
by Richard Firestone,
Allen West,
Simon Warwick-Smith
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Sounds reasonable to me (if I were a liberal)
Even an airburst should leave its mark, so the scientists think the Laurentide Ice Sheet absorbed much of the impact.
Once put out, the fires would have left a barren landscape devoid of food for any remaining animals.
I wonder who did that?
But 3 miles? Nope.
WRITE! WRITE! WRITE! WRITE! TILL YOU RUN OUT OF INK IN YOUR PEN!
Bombard the Democrats as well, especially the ones that ran on an anti immigration plank and the ones in marginal districts who could be vulnerable. keep pounding on them.
yes, about the same time.
A little confusing isn’t it. I kinda got the impression that the comet impacted a ice field near the great lakes, even thou the article stated exploded in the atmosphere. Maybe he/sho considers ice a mile or more high atmosphere? LOL.
I have a problem with people who formulate theories with SO MANY guesses and assumptions, each one built upon the next.
(Re-read the article.)
True, but a comet isn't solid like an asteroid, so if it hit at a shallow angle much of it could have burned away in the atmosphere and ground impacts could have been limited to much smaller fragments.
Assumptions and guesses are the beginning of inquiry. Without them, all we would have would be stumbling about attributing everything to "spirits" or "humours" without the first attempt to explain them. We would simply be saying, "it just is".
As for your exhortation to "re-read the article", please do not talk down to me. I read the article several times, and I am quite clear on the implications of the wording that was used. If I have no ironclad evidence of what happened, I will form a hypothesis and attempt to prove or disprove it. Either way, I've made progress, as long as I do not assume that I have the final answer.
OMG, that's funny! You get credit for posting it first!
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