Posted on 08/15/2007 5:32:04 PM PDT by baynut
A "black mat" of algal growth in Arizona marks the extinction of mammoths 12,900 years ago
New scientific findings suggest that a large comet may have exploded over North America 12,900 years ago, explaining riddles that scientists have wrestled with for decades, including an abrupt cooling of much of the planet and the extinction of large mammals. The discovery was made by scientists from the University of California at Santa Barbara and their colleagues. James Kennett, a paleoceanographer at the university, said that the discovery may explain some of the highly debated geologic controversies of recent decades.
The period in question is called the Younger Dryas, an interval of abrupt cooling that lasted for about 1,000 years and occurred at the beginning of an inter-glacial warm period. Evidence for the temperature change is recorded in marine sediments and ice cores.
According to the scientists, the comet before fragmentation must have been about four kilometers across, and either exploded in the atmosphere or had fragments hit the Laurentide ice sheet in the northeastern North America.
Wildfires across the continent would have resulted from the fiery impact, killing off vegetation that was the food supply of many of larger mammals like the woolly mammoths, causing them to go extinct.
Since the Clovis people of North America hunted the mammoths as a major source of their food, they too would have been affected by the impact. Their culture eventually died out.
The scientific team visited more than a dozen archaeological sites in North America, where they found high concentrations of iridium, an element that is rare on Earth, and is almost exclusively associated with extraterrestrial objects such as comets and meteorites.
They also found metallic microspherules in the comet fragments; these microspherules contained nano-diamonds. The comet also carried carbon molecules called fullerenes (buckyballs), with gases trapped inside that indicated an extraterrestrial origin.
The team concluded that the impact of the comet likely destabilized a large portion of the Laurentide ice sheet, causing a high volume of freshwater to flow into the north Atlantic and Arctic Oceans.
"This, in turn, would have caused a major disruption of the ocean's circulation, leading to a cooler atmosphere and the glaciation of the Younger Dryas period," said Kennett. "We found evidence of the impact as far west as the Santa Barbara Channel Islands."
NSF's Paleoclimate Program funded the research.
Bush’s Fault for not signing the Kyoto Protocol, no doubt.
Meteors are not bombs, either, but judging by the Tunguska event of 1908 and the Barringer crater, they explode just fine.
Get anything with mass going fast enough and it will always explode on meeting the denser part of our atmostphere.
If it explodes every 3600 years they should call it Houdini...
Just saying...
What does post refer to?
It doesn’t explode every 3600 years, it passes through our inner solar system, causing an increase in volcanic and seismic activity due to it’s gravitational pull.
LOL, NO IT ISN’T. MY WIFE USED MY ACCOUNT TO SEND ME DIRECTIONS. BUT SHE TOOK SOME LIBERTIES. I TOLD HER NEXT TIME TO EMAIL IT TO MY HANDLE HERE.
SORRY ABOUT THAT
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine in
the History of Civilization
by Richard Firestone,
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It’s a shame we have never been able to study a comet in captivity. :p
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
Catastrophic Comet Chilled and Killed Ice Age Beasts (and Clovis people)
Live Science | 05/21/07 | Jeanna Bryner
Posted on 05/22/2007 1:16:48 AM EDT by TigerLikesRooster
http://www.freerepublic.com/focus/f-news/1837610/posts
Oregon Researchers Involved In New Clovis-Age Impact Theory (More)
Eureka Alert
Posted on 05/23/2007 5:30:19 PM EDT by blam
http://www.freerepublic.com/focus/f-news/1838660/posts
Comet May Have Doomed Mammoths
Red Orbit | 5-26-07 | Betsy Mason
Posted on 05/26/2007 9:12:53 AM EDT by Renfield
http://www.freerepublic.com/focus/f-news/1840136/posts
Ice Age Ends Smashingly: Did A Comet Blow Up Over Eastern Canada?
(More) (Carolina Bays)
Science News | 6-1-2007 | Sid Perkins
Posted on 06/02/2007 6:14:23 PM EDT by blam
http://www.freerepublic.com/focus/f-news/1843831/posts
Comet Theory Collides With Clovis Research,
May Explain Disappearance of Ancient People
University of South Carolina(USC News) | June 28, 2007 | Staff
Posted on 08/04/2007 2:29:34 AM EDT by ForGod’sSake
http://www.freerepublic.com/focus/f-news/1876220/posts
Rare Meteor Shower To Shed Light On Dangerous Comets
New Scientist | 8-8-2007 | Stephen Battersby
Posted on 08/08/2007 6:08:54 PM EDT by blam
http://www.freerepublic.com/focus/f-news/1878374/posts
bump
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Sounded like a fancy term for global warming, so I looked it up and yeah, it is a fancy term for global warming. I guess we wouldn't want to confuse people between real inter-glacial warm periods and AlGore's global warming "let's get rich off carbon credits" crisis.
"StucturedChaos gets Directions from Wife"
I'm wondering what definition of explode you would choose. No one really knows what happened at Tunguska, and Barringer is just an impact crater. When an airplane crashes into the ground and debris is scattered all over the place no one would suggest that an explosion occurred unless the event were accompanied by a rapid combustion of fuel. (oxidation or other exothermic reaction)
ML/NJ
Did you really understand the reference to "St. Valentine's Day Massacre"?
ML/NJ
from the tradition of the Cashinaua, the aborigines of western Brazil. Quoted by Bellamy, Moons, Myths and Man. p. 80.
Nice!
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