Skip to comments.Did a Comet Hit Earth 12,000 Years Ago?
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."
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.
SCIAM’s version and a link to the abstract
You know... lipstick on that thing... it makes me ask, WHY? Is the lipstick going to make anything better?
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.
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
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Thanks for the pic. Happy New Year!
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?
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?
Well of course not. Didn’t you know that the Bible tells us the Earth is just 6,000 years old?
when will we ever learn
“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
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
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
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
Supernova Storm Wiped Out Mammoths?
Discovery News | 09/28/05 | Jennifer Viegas
Posted on 10/05/2005 2:47:27 AM EDT by planetesimal
Supernova Storm Wiped Out Mammoths?
Discovery News | Sept. 28, 2005 | Jennifer Viegas
Posted on 10/17/2005 11:57:32 AM EDT by Fzob
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
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
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
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
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
Oregon Researchers Involved In New Clovis-Age Impact Theory (More)
Posted on 05/23/2007 5:30:19 PM EDT by blam
Comet May Have Doomed Mammoths
Red Orbit | 5-26-07 | Betsy Mason
Posted on 05/26/2007 9:12:53 AM EDT by Renfield
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
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
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
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
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
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
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
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
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
Great beasts peppered from space
BBC News | 12-11-07
Posted on 12/12/2007 9:55:00 AM PST by Renfield
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Red lipstick on anyone has never made sense to me.
Welll... except maybe an Asian hooker. LOL
Was the Burkle impact close enough to this iridium layer? It hit in the Indian Ocean.
Thanks so much. Helps clarify things. :-)
And with greeings from President Carter and U.N. Secretary General Waldheim.
Last upper molar from the bed of the lower Mamontovaya River (N-MAM-6) BC 2574-2464
Tusk (8 cm diameter (d)) from the bed of the lower Neozhydannaya River BC 2192-2038
Fossils of mammoths, bison, cave bears and horses all seem to disappear from parts of Alaska and Siberia around
35,000 years ago.
“And then they show up again around 10,000 years later,” he said. “So they came in from elsewhere.”
Gillette believes that present-day vegetation in the area is similar to what was here 11,500 years ago. Mammoth remains are most often found in areas that were covered by grasslands during the last Ice Age; in this area, there were likely both conifers and grasses, probably fed by a good water source. The mammoths co-existed with other now-extinct species, such as saber tooth tigers, giant ground sloths, musk oxen, camels, horses, tapirs, and lions.
Hey...give a guy a warning or something!
The Scientific American version and a link to the abstract??
Have you no pity?
We'll be lucky if First Contact doesn't degenerate immediately into an interstellar war of extermination. With us as the exterminatees.
All I can say about this is “DUCK!”
Thanks for the links.
FReepmail me if you want on or off my health and science ping list.
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