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Did a Comet Hit Earth 12,000 Years Ago?
Scientific American ^ | January 2, 2009 | David Biello

Posted on 01/02/2009 6:02:32 PM PST by neverdem

Nanodiamonds found across North America suggest that major climate change could have been cosmically instigated

Roughly 12,900 years ago, massive global cooling kicked in abruptly, along with the end of the line for some 35 different mammal species, including the mammoth, as well as the so-called Clovis culture of prehistoric North Americans. Various theories have been proposed for the die-off, ranging from abrupt climate change to overhunting once humans were let loose on the wilds of North America. But now nanodiamonds found in the sediments from this time period point to an alternative: a massive explosion or explosions by a fragmentary comet, similar to but even larger than the Tunguska event of 1908 in Siberia.

Sediments from six sites across North America—Murray Springs, Ariz.; Bull Creek, Okla.; Gainey, Mich.; Topper, S.C.; Lake Hind, Manitoba; and Chobot, Alberta—yielded such teensy diamonds, which only occur in sediment exposed to extreme temperatures and pressures, such as those from an explosion or impact, according to new research published today in Science.

The discovery lends support to a theory first advanced last year in that some type of cosmic impact or impacts—a fragmented comet bursting in the atmosphere or raining down on the oceans—set off the more than 1,300-year cooling period in the Northern Hemisphere known as the Younger Dryas for the abundance of an alpine flower's pollen found during the interval.

The cooling period interrupted an extended warming out of an ice age predicted by slight changes in Earth's orbit (known as Milankovitch cycles) that continues today. And it remains an unexplained anomaly in the climate record.

But a series of cometary fragments exploding over North America might explain a layer of soil immediately prior to the cooling containing unusually high levels of iridium—an element more common in cosmic wanderers like meteoroids than in Earth's crust. Paired with the fact that this layer occurs directly before the extinction of at least 35 genera of large mammals, including mammoths, it is strong circumstantial evidence for a cosmic event.

"Very strong impact indicators are found in the sediments directly above, and often shrouding in the case of Murray Springs, the remains of these animals and the people who were hunting them," says archaeologist and study co-author Doug Kennett of the University of Oregon in Eugene, the son in the father–son team helping to advance the new impact theory. "Is it a comet? Is it a carbonaceous chondrite? Was it fragmented? Was it focused? Based on the distribution of the diamonds, it was certainly large scale."

Preliminary searches further afield—Europe, Asia and South America—have turned up similar minerals and elements in sediments of the same age, Kennett says, and his own work on California's Channel Islands tells a tale of a massive burn-off, followed by erosion and a total change in the flora of the region.

"It's consistent with a fragmentary body breaking up with air shocks and possible surface impacts in various parts of North America. It could be above the ice sheet or offshore in the ocean," he says, explaining why no impact crater(s) has been found to date. "Immediate effects on the ground include high temperatures and pressures triggering major transformations of the vegetation, knocking trees over but also burning."

And that would make the climate shift of the Younger Dryas a closer cousin to the massive asteroid impact that wiped out the dinosaurs 65 million years ago. "This is an event that happened on one day," Kennett notes. "We're going to need high-resolution climate records, archaeological records, paleontological records to try to explore the effects."


TOPICS: Culture/Society; News/Current Events; Testing
KEYWORDS: catastrophism; chondrite; climatechange; clovis; clovisimpact; globalcooling; godsgravesglyphs; impact; lakecuitzeo; maunderminimum; megafaunaextinction; megafuanaextinction; mexico; milankovitch; milankovitchcycles; nanodiamonds; pleistocene; solarflares; youngerdryas
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DEEP IMPACT?: This 40 centimeter band of dark sediment uncovered at Murray Spring, Ariz., may indicate a cosmic impact or explosion that kicked off a period of global cooling and a mass extinction in North America.
Courtesy of Doug Kennett

Nanodiamonds in the Younger Dryas Boundary Sediment Layer
1 posted on 01/02/2009 6:02:34 PM PST by neverdem
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To: neverdem
"Yes. I was there."


2 posted on 01/02/2009 6:04:39 PM PST by SIDENET ("It was a different time, you understand." - Wallace "Suitcase" Jefferson)
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To: neverdem
Various theories have been proposed for the die-off, ... overhunting once humans were let loose on the wilds of North America.

Never made much sense to me. This would require a truly massive human population for a hunter-gatherer economy. There just isn't really any evidence of so many people being around then.

3 posted on 01/02/2009 6:06:24 PM PST by Sherman Logan (Everyone has a right to his own opinion, but not to his own facts.)
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To: TXnMA; Pharmboy; Coyoteman; djf; blam; SunkenCiv; gleeaikin

SCIAM’s version and a link to the abstract


4 posted on 01/02/2009 6:11:18 PM PST by neverdem (Xin loi minh oi)
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To: SIDENET

You know... lipstick on that thing... it makes me ask, WHY? Is the lipstick going to make anything better?


5 posted on 01/02/2009 6:12:29 PM PST by Mobile Vulgus
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To: Sherman Logan
Never made much sense to me.

From the link:

In the second report, John Alroy of the University of California at Santa Barbara describes a computer simulation of the end-Pleistocene megafaunal extinction in North America showing that even low levels of human hunting would have driven the Ice Age behemoths out of existence. Importantly, the simulation, which assumes a slow human population growth rate and low maximum hunting efforts, correctly predicts the fate of 32 out of 41 megafaunal species. These findings, Alroy argues, show that in fact anthropogenic extinction was unavoidable. "The overkill model thus serves as a parable of resource exploitation," he concludes, "providing a clear mechanism for a geologically instantaneous ecological catastrophe that was too gradual to be perceived by the people who unleashed it."

I never heard of it before either. Never get surprised by a Malthusian with a computer model.

6 posted on 01/02/2009 6:22:45 PM PST by neverdem (Xin loi minh oi)
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The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization

by Richard Firestone,
Allen West, and
Simon Warwick-Smith


7 posted on 01/02/2009 6:23:20 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/_______Profile finally updated Saturday, December 6, 2008 !!!)
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To: neverdem
Thanks neverdem. No ping, just adding (lots of recent duplicates).
 
Catastrophism
 
· join · view topics · view or post blog · bookmark · post new topic ·
 

· join list or digest · view topics · view or post blog · bookmark · post a topic ·

 
Gods
Graves
Glyphs
Note: this topic is from .

Blast from the Past.

Just adding to the catalog, not sending a general distribution.

To all -- please ping me to other topics which are appropriate for the GGG list.
GGG managers are SunkenCiv, StayAt HomeMother, and Ernest_at_the_Beach
 

· Google · Archaeologica · ArchaeoBlog · Archaeology · Biblical Archaeology Society ·
· Discover · Nat Geographic · Texas AM Anthro News · Yahoo Anthro & Archaeo ·
· The Archaeology Channel · Excerpt, or Link only? · cgk's list of ping lists ·


8 posted on 01/02/2009 6:23:23 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/_______Profile finally updated Saturday, December 6, 2008 !!!)
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To: SIDENET

Thanks for the pic. Happy New Year!


9 posted on 01/02/2009 6:24:27 PM PST by neverdem (Xin loi minh oi)
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To: neverdem

The problem with this theory is that many of the same species survived just fine in Asia. Why would humans exterminate megafauna in N. America but not in Asia?


10 posted on 01/02/2009 6:26:32 PM PST by Sherman Logan (Everyone has a right to his own opinion, but not to his own facts.)
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To: SIDENET
You really don't mind ruining everyone's evening, do you? Instead of posting Maddie's photo, you could have posted a photo of her separated by birth brother, which isn't nearly so upsetting:


11 posted on 01/02/2009 6:29:14 PM PST by xJones
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To: neverdem

Speaking of cosmic stuff, is there anyone here that did not know that Voyager 1 is still operational and is currently in interstellar space and approaching the heliopause which is outside out our star system?


12 posted on 01/02/2009 6:39:54 PM PST by eaglestar
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To: neverdem

Well of course not. Didn’t you know that the Bible tells us the Earth is just 6,000 years old?


13 posted on 01/02/2009 6:40:31 PM PST by gracesdad
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To: neverdem
Obviously the second ice age was caused by early man's campfires, it could have been avoided by the taxation and regulation of firewood supplies,

when will we ever learn

14 posted on 01/02/2009 6:55:45 PM PST by KTM rider (keep thy powder dry, gird thy loins, and brace for the winds of change)
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To: xJones
The original 2 Bagger


15 posted on 01/02/2009 6:57:25 PM PST by ThreePuttinDude (o)(o)
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“Blast from the Past.” — mea culpa, should have edited that out.

Here’s the list of topics about this, all are worth checking out over the next couple of, well, weeks, months, whatever is required. ;’)

What killed the mammoths and other behemoths?
FR Post 6-6-2 | Interview with Ross MacPhee
Posted on 06/05/2002 6:34:28 PM EDT by vannrox
http://www.freerepublic.com/focus/f-news/695260/posts

Ancient Atomic Warfare - Religious texts and geological evidence
New York Herald Tribune on February 16, 1947 | Ivan T. Sanderson
Posted on 07/22/2002 5:01:00 PM EDT by vannrox
http://www.freerepublic.com/focus/f-news/720501/posts

Supernova debris found on Earth
News@Nature.com | 02 November 2004 | Mark Peplow
Posted on 11/24/2004 4:22:08 PM EST by Phsstpok
http://www.freerepublic.com/focus/news/1287848/posts

Deep freeze dealt death knell to bison (Ice Age)
CBC News Online | 11/25/2004
Posted on 11/25/2004 10:25:47 PM EST by Fatalis
http://www.freerepublic.com/focus/f-news/1288596/posts

Supernova Storm Wiped Out Mammoths?
Discovery News | 09/28/05 | Jennifer Viegas
Posted on 10/05/2005 2:47:27 AM EDT by planetesimal
http://www.freerepublic.com/focus/news/1496844/posts

Supernova Storm Wiped Out Mammoths?
Discovery News | Sept. 28, 2005 | Jennifer Viegas
Posted on 10/17/2005 11:57:32 AM EDT by Fzob
http://www.freerepublic.com/focus/news/1503957/posts

Scientist: Comets Blasted Early Americans
ap on Yahoo | 10/28/05 | Meg Kinnard - ap
Posted on 10/28/2005 6:33:11 PM PDT by NormsRevenge
http://www.freerepublic.com/focus/news/1511330/posts

Terrestrial Evidence of a Nuclear Catastrophe in Paleoindian Times
Mammoth Trumpet | March 2001 | Firestone/Topping
Posted on 07/24/2006 3:03:03 AM EDT by ForGod’sSake
http://www.freerepublic.com/focus/news/1671134/posts

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

Climate alarmists lose another piece of evidence
enterstageright | 6/11/2007 | Dennis T. Avery
Posted on 06/11/2007 1:11:38 PM EDT by Neville72
http://www.freerepublic.com/focus/f-news/1848385/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

NSF Press Release:
Comet May Have Exploded Over North America 13,000 Years Ago
National Science Foundation Press Release | August 14, 2007 | Cheryl Dybas, NSF
Posted on 08/15/2007 8:32:04 PM EDT by baynut
http://www.freerepublic.com/focus/f-news/1881784/posts

Research Team Says Extraterrestrial Impact To Blame For Ice Age Extinctions (More)
Eureka Alert | Northern Arizona University - Lisa Nelson
Posted on 09/25/2007 3:58:19 PM EDT by blam
http://www.freerepublic.com/focus/f-chat/1902003/posts

Cosmic blast may have killed off megafauna
Scientists say early humans doomed, too
Boston Globe | September 27, 2007 | Colin Nickerson
Posted on 09/25/2007 9:45:11 PM EDT by baynut
http://www.freerepublic.com/focus/f-news/1902154/posts

Cosmic blast may have killed off megafauna
Scientists say early humans doomed, too
Boston Globe | September 25, 2007 | Colin Nickerson
Posted on 09/26/2007 9:11:48 AM EDT by baynut
http://www.freerepublic.com/focus/f-news/1902361/posts

Evidence for an extraterrestrial impact 12,900 years ago
Proceedings of the National Academy of Sciences
October 9, 2007, Vol. 104 | September 27, 2007 | R. B. Firestone, et. al.
Posted on 09/30/2007 1:14:28 PM EDT by baynut
http://www.freerepublic.com/focus/f-chat/1904474/posts

The End of Eden: The Comet That Changed Civilization
amazon | Oct. 8, 2007
Posted on 10/09/2007 2:47:23 AM EDT by doug from upland
http://www.freerepublic.com/focus/f-news/1908525/posts

Great beasts peppered from space
BBC News | 12-11-07
Posted on 12/12/2007 9:55:00 AM PST by Renfield
http://www.freerepublic.com/focus/f-chat/1938461/posts

Did Comets Cause Ancient American Extinctions?
National Geographic News | 5-6-2008 | Anne Casselman
Posted on 05/07/2008 6:40:10 PM PDT by blam
http://www.freerepublic.com/focus/news/2012792/posts

Al Goodyear And The Secrets Of Ancient Americans
Free Times | 5-14/20-2008 | Ron Aiken
Posted on 05/15/2008 3:25:21 PM PDT by blam
http://www.freerepublic.com/focus/news/2016537/posts

Life Survived Catastrophic Space Rock Impact [Chesapeake Bay area]
Space.com | June 26, 2008 | Jeanna Bryner
Posted on 06/26/2008 8:04:37 PM PDT by ETL
http://www.freerepublic.com/focus/f-news/2037094/posts

First Humans To Settle Americas Came From Europe, Not From Asia....
Science Daily | 7-1-08
Posted on 07/03/2008 4:55:14 AM PDT by Renfield
http://www.freerepublic.com/focus/chat/2040167/posts

Exploding Asteroid Theory Strengthened By New Evidence Located In Ohio, Indiana
Physorg | 7-1-2008 | University of Cincinnati
Posted on 07/02/2008 3:27:51 PM PDT by blam
http://www.freerepublic.com/focus/chat/2039949/posts

Diamonds Rained Down During Ice Age
Live Science | JUL 7, 2008 | Ker Than
Posted on 07/07/2008 2:05:25 PM PDT by decimon
http://www.freerepublic.com/focus/f-chat/2042031/posts

Diamonds Rained Down During Ice Age ($$$)
LiveScience.com | July 7, 2008 | Ker Than
Posted on 07/08/2008 9:50:22 PM PDT by max americana
http://www.freerepublic.com/focus/chat/2042770/posts

Tracking down abrupt climate changes
(Rapid natural climate change 12,700 years ago)
Helmholtz Association of German Research Centres | Aug 1, 2008 | Unknown
Posted on 08/01/2008 11:03:47 AM PDT by decimon
http://www.freerepublic.com/focus/news/2054995/posts

Mammoth Mystery: The Beasts’ Final Years
Live Science | Sep 4, 2008 | Charles Q. Choi
Posted on 09/04/2008 10:42:29 AM PDT by decimon
http://www.freerepublic.com/focus/chat/2074657/posts

Scientists find signs of 13,000-year-old extinction event
Chicago Tribune | January 2, 2009 | Robert Mitchum
Posted on 01/01/2009 2:09:17 PM PST by neverdem
http://www.freerepublic.com/focus/news/2157352/posts

Scientists say comet killed off mammoths, saber-toothed tigers
www.physorg.com | 02 JAN 2009 | By Robert Mitchum
Posted on 01/02/2009 7:44:26 AM PST by Red Badger
http://www.freerepublic.com/focus/news/2157621/posts

Diamonds Linked to Quick Cooling Eons Ago
NY Times | January 2, 2009 | KENNETH CHANG
Posted on 01/02/2009 9:02:31 AM PST by Pharmboy
http://www.freerepublic.com/focus/news/2157663/posts

Six North American sites hold 12,900-year-old nanodiamond-rich soil
www.physorg.com | 01-01-2009 | Source: University of Oregon in Nanotechnology / Materials
Posted on 01/02/2009 10:44:35 AM PST by Red Badger
http://www.freerepublic.com/focus/news/2157721/posts

Kankakee Sand Islands:

Research Casts New Light On History Of North America
Newswise | 7-1-2008 | Valparaiso University
Posted on 07/01/2008 10:26:26 AM PDT by blam
http://www.freerepublic.com/focus/f-news/2039278/posts

First Humans To Settle Americas Came From Europe, Not From Asia Over Bering Strait -
ScienceDaily | July 17, 2008
Posted on 07/16/2008 8:02:06 PM PDT by Free ThinkerNY
http://www.freerepublic.com/focus/chat/2046692/posts


16 posted on 01/02/2009 6:58:15 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/_______Profile finally updated Saturday, December 6, 2008 !!!)
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To: Mobile Vulgus

Red lipstick on anyone has never made sense to me.


17 posted on 01/02/2009 7:02:57 PM PST by Martins kid
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To: Martins kid

Welll... except maybe an Asian hooker. LOL


18 posted on 01/02/2009 7:10:19 PM PST by Mobile Vulgus
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To: neverdem
Comet Once Struck Earth; Women, Minorities Hardest Hit-- NY Times
19 posted on 01/02/2009 7:19:51 PM PST by pabianice
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To: ThreePuttinDude

http://www.youtube.com/watch?v=7YYMYNb4QZ4


20 posted on 01/02/2009 7:28:49 PM PST by eaglestar
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