Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

Comet theory false; doesn't explain Ice Age cold snap, Clovis changes, animal extinction
Science Codex ^ | 5-13-2014

Posted on 05/17/2014 12:06:11 PM PDT by Renfield

Controversy over what sparked the Younger Dryas, a brief return to near glacial conditions at the end of the Ice Age, includes a theory that it was caused by a comet hitting the Earth.

As proof, proponents point to sediments containing deposits they believe could result only from a cosmic impact.

Now a new study disproves that theory, said archaeologist David Meltzer, Southern Methodist University, Dallas. Meltzer is lead author on the study and an expert in the Clovis culture, the peoples who lived in North America at the end of the Ice Age.

Meltzer's research team found that nearly all sediment layers purported to be from the Ice Age at 29 sites in North America and on three other continents are actually either much younger or much older.

Scientists agree that the brief episode at the end of the Ice Age — officially known as the Younger Dryas for a flower that flourished at that time — sparked widespread cooling of the Earth 12,800 years ago and that this cool period lasted for 1,000 years. But theories about the cause of this abrupt climate change are numerous. They range from changes in ocean circulation patterns caused by glacial meltwater entering the ocean to the cosmic-impact theory.

The cosmic-impact theory is said to be supported by the presence of geological indicators that are extraterrestrial in origin. However a review of the dating of the sediments at the 29 sites reported to have such indicators proves the cosmic-impact theory false, said Meltzer.

Meltzer and his co-authors found that only three of 29 sites commonly referenced to support the cosmic-impact theory actually date to the window of time for the Ice Age.

The findings, "Chronological evidence fails to support claim of an isochronous widespread layer of cosmic impact indicators dated to 12,800 years ago," were reported May 12, 2014, in the Proceedings of the National Academy of Sciences.

Co-authors were Vance T. Holliday and D. Shane Miller, both from the University of Arizona; and Michael D. Cannon, SWCA Environmental Consultants Inc., Salt Lake City, Utah.

"The supposed impact markers are undated or significantly older or younger than 12,800 years ago," report the authors. "Either there were many more impacts than supposed, including one as recently as 5 centuries ago, or, far more likely, these are not extraterrestrial impact markers."

Dating of purported Younger Dryas sites proves unreliable

The Younger Dryas Impact Hypothesis rests heavily on the claim that there is a Younger Dryas boundary layer at 29 sites in the Americas and elsewhere that contains deposits of supposed extraterrestrial origin that date to a 300-year span centered on 12,800 years ago.

The deposits include magnetic grains with iridium, magnetic microspherules, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds, and fullerenes with extraterrestrial helium, all said to result from a comet or other cosmic event hitting the Earth.

Meltzer and his colleagues tested that hypothesis by investigating the existing stratigraphic and chronological data sets reported in the published scientific literature and accepted as proof by cosmic-impact proponents, to determine if these markers dated to the onset of the Younger Dryas.

They sorted the 29 sites by the availability of radiometric or numeric ages and then the type of age control, if available, and whether the age control is secure.

The researchers found that three sites lack absolute age control: at Chobot, Alberta, the three Clovis points found lack stratigraphic context, and the majority of other diagnostic artifacts are younger than Clovis by thousands of years; at Morley, Alberta, ridges are assumed without evidence to be chronologically correlated with Ice Age hills 2,600 kilometers away; and at Paw Paw Cove, Maryland, horizontal integrity of the Clovis artifacts found is compromised, according to that site's principal archaeologist.

The remaining 26 sites have radiometric or other potential numeric ages, but only three date to the Younger Dryas boundary layer.

At eight of those sites, the ages are unrelated to the supposed Younger Dryas boundary layer, as for example at Gainey, Michigan, where extensive stratigraphic mixing of artifacts found at the site makes it impossible to know their position to the supposed Younger Dryas boundary layer. Where direct dating did occur, it's sometime after the 16th century A.D.

At Wally's Beach, Alberta, a radiocarbon age of 10,980 purportedly dates extraterrestrial impact markers from sediment in the skull of an extinct horse. In actuality, the date is from an extinct musk ox, and the fossil yielding the supposed impact markers was not dated, nor is there evidence to suggest that the fossils from Wally's Beach are all of the same age or date to the Younger Dryas onset.

At nearly a dozen other sites, the authors report, the chronological results are neither reliable nor valid as a result of significant statistical flaws in the analysis, the omission of ages from the models, and the disregard of statistical uncertainty that accompanies all radiometric dates.

For example, at Lake Cuitzeo, Mexico, Meltzer and his team used the data of previous researchers and applied a fifth-order polynomial regression, but it returned a different equation that put the cosmic-impact markers at a depth well above that which would mark the Younger Dryas onset.

The authors go on to point out that inferences about the ages of supposed Younger Dryas boundary layers are unsupported by replication in more cases than not.

In North America, the Ice Age was marked by the mass extinction of several dozen genera of large mammals, including mammoths, mastodons, American horses, Western camels, two types of deer, ancient bison, giant beaver, giant bears, sabre-toothed cats, giant bears, American cheetahs, and many other animals, as well as plants.


TOPICS: Astronomy; History; Science
KEYWORDS: astronomy; catastrophism; clovisimpact; davidmeltzer; dshanemiller; extinction; godsgravesglyphs; holocene; justdiealready; michaeldcannon; pleistocene; science; vancetholliday; youngerdryas
Navigation: use the links below to view more comments.
first previous 1-2021-4041-45 next last
To: Sherman Logan

Interesting observations but you forgot to address my first point which was actually the main point. The evidence of catastrophe near the end of the last glaciation is global but studiously ignored/suppressed by the scientific community. I daresay you won’t find much in “prestigious” scientific journals. Why is that?


21 posted on 05/18/2014 10:27:20 AM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 20 | View Replies]

To: ForGod'sSake
The evidence of catastrophe near the end of the last glaciation is global

Then why was much of the mega-fauna extinction limited to the Americas?

Here's a classic example of the conflicted PC-person.

http://australianmuseum.net.au/Megafauna-extinction-theories-patterns-of-extinction

Here, the claim is made, "Worldwide, there is no evidence of Indigenous hunter-gatherers systematically hunting nor over-killing megafauna."

This is in blatant conflict with exactly that happening in NZ and Madagascar.

22 posted on 05/18/2014 10:42:42 AM PDT by Sherman Logan
[ Post Reply | Private Reply | To 21 | View Replies]

To: ComputerGuy
I’m not going to hang a completely novel interpretation of the peopling of the Americas from something dredged off the sea bottom 40 years ago

Uhh, dude.

The oceans were much lower then, and most of the evidence of humans from then is probably near the previous seacoast.

IOW, humans then and now tended to hang out at the edge of the water. If you find artifacts, they're likely to be from the ocean bottom.

23 posted on 05/18/2014 10:50:18 AM PDT by Sherman Logan
[ Post Reply | Private Reply | To 17 | View Replies]

To: ForGod'sSake

What is your explanation for this suppression?


24 posted on 05/18/2014 10:51:11 AM PDT by Sherman Logan
[ Post Reply | Private Reply | To 21 | View Replies]

To: Renfield
But theories about the cause of this abrupt climate change are numerous. They range from changes in ocean circulation patterns caused by glacial meltwater entering the ocean to the cosmic-impact theory.

Clearly, the Clovis' SUVs are to blame.

25 posted on 05/18/2014 10:52:16 AM PDT by Colonel_Flagg ("Compromise" means you've already decided you lost.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Explorer89

Thanks Explorer89.


26 posted on 05/18/2014 2:34:17 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/)
[ Post Reply | Private Reply | To 18 | View Replies]

To: ComputerGuy

Thanks CG. He’s one of those go-to guys when a quote is needed from a purported expert, but anyone who claims as he does that all evidence of pre-Clovis sites has been falsified is a scientist in name only.


27 posted on 05/18/2014 2:36:28 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/)
[ Post Reply | Private Reply | To 17 | View Replies]

To: Larry Lucido

Yes, the back of NYC restaurants.


28 posted on 05/18/2014 3:06:17 PM PDT by Sawdring
[ Post Reply | Private Reply | To 19 | View Replies]

To: Sherman Logan
Then why was much of the mega-fauna extinction limited to the Americas?

You might point me to where I can study the remaining megafauna in Europe and Asia, excepting the Asian subcontinent where elephants still roam. As far as I can tell, Australia, with the exception of some overly large marsupials, never had much else in the way of megafauna to start with. A quick search indicates there were mammoths/mastodons on the African continent at one time. I didn't look any further to determine when they went missing. NZ and Madagascar???

There are so many anamolies associated with this time period that trying to put the blame on humans seems a PC endeavor at best and unmitigated propoganda at worst. There are indications of potential cosmic origin, along with pole wanderings, massive volcanism, flooding and enormous waves traversing entire continents; you get the idea...

From this SEARCH check out the first ARTICLE re boneyards in Alaska and almost complete islands composed of mammoth/mastodon remains in and north of Siberia.

29 posted on 05/18/2014 7:07:27 PM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 22 | View Replies]

To: Sherman Logan
What is your explanation for this suppression?

You've been around here long enough that you should have at least become suspicious of the motives of many in the scientific community™. Uniformitarianism/gradualism is the name; lying is their game. Goes back to at least the early Catholic Church. The PTB don't like to be discovered in their ignorance/malfeasance and they will apparently do whatever is necessary to protect their turf, egos, government grants, whatever. JMO of course...

30 posted on 05/18/2014 7:19:05 PM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 24 | View Replies]

To: Renfield

There was a comet, unlike any other thus far observed, that impacted in the Southern Ocean and flooded the former abyss where we evolved. Explained in a slide presentation here:

http://www.threeimpacts-twoevents.com/wp-content/uploads/2013/08/COMET-IMPACT-ANALYSIS-AND-EFFECTS-20Aug2013.pdf

When? Perhaps it caused YD, perhaps it was more recent....


31 posted on 05/18/2014 7:26:44 PM PDT by mj81
[ Post Reply | Private Reply | To 1 | View Replies]

To: Sherman Logan; All

Let’s face it, the Indians did not have repeating rifles like the European invaders of Australia, New Zealand and Madagascar. Also I do not have the impression that the Clovis population was very numerous.


32 posted on 05/21/2014 10:13:52 PM PDT by gleeaikin
[ Post Reply | Private Reply | To 13 | View Replies]

To: gleeaikin

The megafauna of Oz, NZ and Madagascar were not wiped out by European settlers, but respectively by the Aborigines, Maori and Malagasy.

The Aborigines arrived in Oz sometime between 40,000 and 80,000 years ago. They were at a stone-age level and remained there till Euros showed up.

The Maoris arrived in NZ around 1200 to 1300 AD. They were also stone age.

The Malagasy arrive in Madagascar sometime between 500 BC and 500 AD. They came from Indonesia, not the nearby Africa. I don’t know whether they were using metals yet, but they probably were. Indonesia, then as now, was home to a wild variety of cultures and levels of civilization, but there were certainly fairly advanced cultures around. They quite obviously had fairly advanced boat-building capabilities, or they’d never have survived their voyage.

None of these peoples needed guns, or, in the case of at least two of them even metals, to wipe out the native megafauna. Assuming that’s what happened, which it’s pretty clear it did in at least NZ and Madagascar, they being so much more recent.

Extrapolating this to the Americas is, I agree, a big jump due to sheer acreage. But the example of Oz seems to indicate that a continent-sized population of megafauna might indeed be vulnerable to extinction by stone-age human hunters.

All somewhat speculative, but the dates and other history are certainly interesting. The biggest flaw in the “American mega-slaughter” theory, IMO, is the increasing evidence humans were in the Americas for many thousands of years before the extinctions started.

Any such extinction would also seem to imply a rather large human population across North America, the physical evidence for which is darn thin, as you point out. A small band reproducing enough in a relatively short time to create that level of population seems unlikely.

OTOH, the Maoris apparently managed to overpopulate their islands and start fighting over the suddenly scarce resources in just two or three centuries, from just a few canoe-loads at the start. Extrapolating that to the American continent might take just one or two centuries more.


33 posted on 05/22/2014 6:17:45 AM PDT by Sherman Logan
[ Post Reply | Private Reply | To 32 | View Replies]

To: gleeaikin; Sherman Logan

gleeakin, I think what we’ve got here is a “hunted to extinction” crusader. I sent him/her to some links that are pretty compelling re a catastrophic end to the Pleistocene and I’m guessing he/she got a painful whiplash turning away from it. Not only that but evidence of simultaneous megafauna extinctions in other parts of the world besides the Americas which he/she also ignored. I’m also wondering if he/she has read there has been few, if any, human artifacts found dating to within a thousand years or so AFTER the events that took out the megafauna. Indicating of course that whatever snuffed the megafauna likely also snuffed most of the peoples of at least North America. Don’t know about the rest of the world.


34 posted on 05/22/2014 4:14:46 PM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 32 | View Replies]

To: ForGod'sSake; Sherman Logan; SunkenCiv; All

Having read the book that Sunken Civ has posted on this thread, I am inclined to think it was something more solid that a comet, or else a very large one, perhaps a broken up asteroid. For example, there is a picture of the bottom of Lake Michigan which appears to have been hit by either 2 or 3 large objects in a row. There is also evidence of some things striking Siberia or Scandinavia.
The early Australians had many tens of thousands of years to kill the mega fauna. They also may have killed off a pre sapiens homonid about 12,000 years ago called Kow swamp people. In the wall of human evolution in the Smithsonian one of the Kow skulls is in the far right lower corner. It is called homo sapien, but after comparing it to Neanderthal and earlier Heidelbergensis skulls, I am of the opinion it had more in common with the Heidelberg skulls. Really, the only basis for calling it sapiens is the 12,000 age. when the Europeans arrived in Australia the Tasmanian Devil and Tiger were still alive, and I believe other large animals that are now extinct had survived the aboriginies. They did not survive firearms. There are still significant killings and species depletion occurring in Madagascar as well.


35 posted on 05/22/2014 11:29:35 PM PDT by gleeaikin
[ Post Reply | Private Reply | To 34 | View Replies]

To: ForGod'sSake; Sherman Logan; SunkenCiv; blam; All

The descriptions of massive bone yards appear in some of Velikovsky’s writings. I also have a book titled “My Way Was North” in which the author describes a cliff face (I think in Alaska) packed solid with bones being eroded out. Unfortunely it is packed away so I can’t give the more precise information and quote. They were bones of the type appropriate for a 13,000 bc disaster. I could imagine giant tsunamis causing such bone piles.


36 posted on 05/22/2014 11:37:12 PM PDT by gleeaikin
[ Post Reply | Private Reply | To 29 | View Replies]

To: gleeaikin
"The early Australians had many tens of thousands of years to kill the mega fauna. They also may have killed off a pre sapiens homonid about 12,000 years ago called Kow swamp people. In the wall of human evolution in the Smithsonian one of the Kow skulls is in the far right lower corner. It is called homo sapien, but after comparing it to Neanderthal and earlier Heidelbergensis skulls, I am of the opinion it had more in common with the Heidelberg skulls."

Maybe Denisovians?

Kow Swamp People

"The enigma of Kow Swamp is that the skulls are younger than those at Keilor and Willandra Lakes, but appear much more archaic. The people at Kow Swamp had large, long heads with very thick bone, up to 13 mm thick. Their faces were large, wide and projecting, with prominent brow ridges and flat, receding foreheads. From above they show a pronounced inward curvature behind the eye sockets, giving the skull the appearance of a flask. They had enormous teeth and jaws, some even larger than Java Man, Homo erectus (Previously called Pithecanthropus, from the middle Pleistocene of Sangiran."

37 posted on 05/23/2014 7:15:41 AM PDT by blam
[ Post Reply | Private Reply | To 36 | View Replies]

To: gleeaikin
There are still significant killings and species depletion occurring...

No doubt some of it at the hands of Man but when accompanied by evidence of catastrophe??? ONLY if one ignores the catastrophe I suppose. Anyhow, here in East Texas we have something similar occurring, after a fashion. Fire ants! Yep, fire ants have been credited with creating havoc amongst critters that nest on, near or under the ground. Larger young critters are even at risk if mama drops her newborn on or near a fire ant hill. Ground nesting birds like quail are nothing but a memory. I miss the night calls of Bobwhites and Whippoorwills.

38 posted on 05/23/2014 2:11:06 PM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 35 | View Replies]

To: gleeaikin
I could imagine giant tsunamis causing such bone piles.

Truth be told, it's the only thing that comes to mind that COULD explain it. Depositing the bones of millions of disarticulated animals along with splintered trees, volcanic ash, large rocks and sand over hundreds, maybe thousands of miles is tough to overlook but the scientific community™ has done a yeoman's job of it so far. Gives me a case of the RED A$$!

Parenthetically, and re your other post: From many accounts the Smithsonian has been complicit it hiding and/or losing evidence that doesn't fit the uniformitarian or other "consensus" narrative. Such and august institution guilty of fudging the facts??? Say it ain't so...

39 posted on 05/23/2014 2:32:37 PM PDT by ForGod'sSake (What part of "Fundamentally transforming the United States of America" don't the LIV understand?)
[ Post Reply | Private Reply | To 36 | View Replies]

To: blam; All

Maybe I am behind on news, but I thought they only had a few Denisovan teeth, not an actual skull. Has anyone seen the Smithsonian wall of skulls?


40 posted on 05/26/2014 2:49:00 PM PDT by gleeaikin
[ Post Reply | Private Reply | To 37 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-2021-4041-45 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson