Palanth Forum

Forum Boards. => Palaeoenvironmental studies. => : Jacques Cinq-Mars May 22, 2007, 10:41:19 AM



: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars May 22, 2007, 10:41:19 AM
Catastrophism and attendant sensationalism strike again. Move aside Mt. Toba. North America can now claim to have been subjected, at the end of the Pleistocene, to a real cataclysmic event (i.e., a meteoritic impact) of such a cosmic magnitude that it caused the rapid demise (“disappearance”) of the Clovis people and that of its larder. Not to mention that its impact on or over the Laurentide ice sheet caused the latter to melt, letting loose massive amounts of cold water that, having reached the Atlantic ocean, heavily disturbed the oceanic currents, thus interrupting the ongoing deglaciation and causing much of the northern hemisphere to temporarily revert to a mini-deep-freeze called the Younger Dryas.

I’ll wait for the real paper to come out, but, for the time being, I suspect the robustness of this new hypothesis may well be inversely proportional to the sensationalism it has inspired.

Here is an incomplete list of where you can read about this story, hype and all:

from Nature’s Rex Dalton ( HERE (http://www.nature.com/nature/journal/v447/n7142/full/447256a.html) if you subscribe to Nature or if you have some sort of institutional access);

from LiveScience (HERE (http://www.livescience.com/animals/070521_comet_climate.html));

from the BBC (HERE (http://news.bbc.co.uk/2/hi/science/nature/6676461.stm));

from MNBC (HERE (http://www.msnbc.msn.com/id/18789488/));

etc.

Come to think of it, with all the neat glassy spherules I found in Bluefish Cave I, many years ago, I should have gone to Acapulco.

Jacques



: Re: Spherule attack and the demise of Clovis!
: AWSX May 22, 2007, 01:48:16 PM
I have been following the evolution of Firestone's hypothesis for some time. He first proposed that a nuclear bombardment had reset the 14C clock in North America.
The first article and the rebuttals published in The Mammoth Trumpet:
http://www.centerfirstamericans.com/mt.php?a=35&h=firestone
http://www.centerfirstamericans.com/mt.php?a=36&h=firestone
http://www.centerfirstamericans.com/mt.php?a=53&h=firestone
http://www.centerfirstamericans.com/mt.php?a=61&h=firestone

Last year Firestone, West & Warwick-Smith published "The Cycle of Cosmic Catrastophies" which summarized Firestone's search for evidence for what he terms the "Event". He found many mammoth tusks with magnetic spherules cratered into the surface and also collected these magnetic spherules from several Clovis age sites in North America. He also reported finding some unusual atomic isotopes and the carbon spherules, but not much discussion on those latest discoveries. What was missing in the book was any mention of the first hypothesis that the 14C clock had been reset.

In the book he proposed an impact crater at the southern end of Lake Michigan and also proposed that the Carolina Bays were shallow impact craters from this "Event". He also had topographic maps of 'dry bays' across the plains states.  However in the list of papers for the conference in Acapulco, I found no mention of these impact craters. Geological studies of Lake Michigan do not show any evidence for an impact crater and there is material in the Carolina Bays much older than 13,000 years so both of those bits of evidence have apparently been abandoned.

Now Firestone is a Ph.D. nuclear physicist and he does seem to have some evidence that something unusual happened in North America 13,000 years ago, but his search for an impact crater to support his hypothesis has not strengthened his case, so far.

In a way the hype may be good in that it may cause more research into what actually caused the Younger Dryas, the megafauna extinctions and the demise of Clovis Culture. In any case, it will be an interesting story to follow.


: Re: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars May 23, 2007, 10:02:07 AM
I have been following the evolution of Firestone's hypothesis for some time. He first proposed that a nuclear bombardment had reset the 14C clock in North America.
The first article and the rebuttals published in The Mammoth Trumpet:
http://www.centerfirstamericans.com/mt.php?a=35&h=firestone
http://www.centerfirstamericans.com/mt.php?a=36&h=firestone
http://www.centerfirstamericans.com/mt.php?a=53&h=firestone
http://www.centerfirstamericans.com/mt.php?a=61&h=firestone

Last year Firestone, West & Warwick-Smith published "The Cycle of Cosmic Catrastophies" which summarized Firestone's search for evidence for what he terms the "Event". He found many mammoth tusks with magnetic spherules cratered into the surface and also collected these magnetic spherules from several Clovis age sites in North America. He also reported finding some unusual atomic isotopes and the carbon spherules, but not much discussion on those latest discoveries. What was missing in the book was any mention of the first hypothesis that the 14C clock had been reset.

In the book he proposed an impact crater at the southern end of Lake Michigan and also proposed that the Carolina Bays were shallow impact craters from this "Event". He also had topographic maps of 'dry bays' across the plains states.  However in the list of papers for the conference in Acapulco, I found no mention of these impact craters. Geological studies of Lake Michigan do not show any evidence for an impact crater and there is material in the Carolina Bays much older than 13,000 years so both of those bits of evidence have apparently been abandoned.

Now Firestone is a Ph.D. nuclear physicist and he does seem to have some evidence that something unusual happened in North America 13,000 years ago, but his search for an impact crater to support his hypothesis has not strengthened his case, so far.

In a way the hype may be good in that it may cause more research into what actually caused the Younger Dryas, the megafauna extinctions and the demise of Clovis Culture. In any case, it will be an interesting story to follow.
Dear Allan,

Thanks for passing on this complementary information. I guess I should have spent more time monitoring the Mammoth Trumpet. As for the “hype [being] good…”, we’ll see. I am sure that many of the scientists who have worked for years trying to figure out what may have caused the onset of Younger Dryas will soon chime in. As I have noted earlier, we should wait to see the real paper and the expectable rejoinders. In the meantime, have a look HERE (http://www.newswise.com/articles/view/530208/) at one of the most recent, coherent release I have read so far on this story.

By the way, today is the day in Acapulco, and I won’t be there to show my little vial full of spherules!

Jacques


: Re: Spherule attack and the demise of Clovis!
: AWSX May 23, 2007, 11:21:31 AM
Jacques,
While we are waiting on the papers, I would like to hear more about those spherules you collected. Were those found inside the cave and do you have any dates for the strata where they were found? What are the diameters and has any analysis been done?

One of the first things Firestone did when he was collecting was to take a 'supermagnet' to collect samples from various layers at some of the excavations. In fact, at Topper he used the technique to identify the top of the Clovis Layer at one of the test pits. Are any of your spherules magnetic?

Allan Shumaker


: Re: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars May 23, 2007, 01:24:55 PM
Jacques,
While we are waiting on the papers, I would like to hear more about those spherules you collected. Were those found inside the cave and do you have any dates for the strata where they were found? What are the diameters and has any analysis been done?

One of the first things Firestone did when he was collecting was to take a 'supermagnet' to collect samples from various layers at some of the excavations. In fact, at Topper he used the technique to identify the top of the Clovis Layer at one of the test pits. Are any of your spherules magnetic?

Allan Shumaker
The Bluefish "spherules" I was somewhat jokingly talking about, are presently housed at the Canadian Museum of Civilzation, in some dark, scientifically uncared for, anonymous drawer, about three hours from where I live. To provide you with a detailed answer, I would have to drive and spend a few days there! As far as I can recall, at a distance, they were obtained from the large quantities of dirt samples that were collected during the Bluefish Cave I excavation and later water-screened and processed. If my memory serves me right, they were found to occur mostly (?) in the upper units of the deposit which could well correspond in terms of age to the time range of the "catastrophic" event under discussion. As for size, all I can say (again from memory) is that they were in the -1mm range, i.e., very-micro-glassy-beads. After asking an uninterested geologist, I just ended up calling them "tektites" and left it at that. I had other things to do. In other words, no analysis has been done.

Jacques


: Re: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars May 24, 2007, 10:42:58 AM
For your information:

The National Geographic News (HERE (http://news.nationalgeographic.com/news/2007/05/070523-comet-impact.html)) now has its own piece on the cosmic catastrophe under discussion. Contrary to most of the other sensationalistic reports that have surfaced so far, it presents a few interesting cautionary comments from David Meltzer:

Findings Questioned

David Meltzer is an archaeologist at Southern Methodist University in Dallas, Texas, who is not part of the research team. He said the theory is far from proven.

First, he said, the team must prove a comet did in fact hit Earth 12,900 years ago, an issue that geologists will eventually resolve.

Then, if an impact is demonstrated, the team has to show what the effects were.

"At the moment, the issues are far more complicated than all animals died at once and people suffered tremendously," he said.

For example, some the big animals went extinct well before the proposed impact, and others disappear later.

Nor does Meltzer see evidence for the disappearance of Clovis populations.

"At least out on the [Great] Plains, populations are booming [at the time of impact], they're not declining at all despite this horrific global conflagration," he said.

… and this is just the beginning of the “chiming in” exercise I mentioned earlier.

Jacques



: Re: Spherule attack and the demise of Clovis!
: rmacfarl May 28, 2007, 03:08:09 AM
The Bluefish "spherules" I was somewhat jokingly talking about, are presently housed at the Canadian Museum of Civilzation, in some dark, scientifically uncared for, anonymous drawer, about three hours from where I live. To provide you with a detailed answer, I would have to drive and spend a few days there! As far as I can recall, at a distance, they were obtained from the large quantities of dirt samples that were collected during the Bluefish Cave I excavation and later water-screened and processed. If my memory serves me right, they were found to occur mostly (?) in the upper units of the deposit which could well correspond in terms of age to the time range of the "catastrophic" event under discussion. As for size, all I can say (again from memory) is that they were in the -1mm range, i.e., very-micro-glassy-beads. After asking an uninterested geologist, I just ended up calling them "tektites" and left it at that. I had other things to do. In other words, no analysis has been done.

Jacques

From such throwaways are the pearls of serendipity discovered! Sounds to me, Jacques, like you should get on your bike to the Canadian Museum of Civilzation & find that anonymous drawer, toute suite!

Ross Macfarlane :-)


: Re: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars May 28, 2007, 01:32:05 PM
The Bluefish "spherules" I was somewhat jokingly talking about, are presently housed at the Canadian Museum of Civilzation, in some dark, scientifically uncared for, anonymous drawer, about three hours from where I live. To provide you with a detailed answer, I would have to drive and spend a few days there! As far as I can recall, at a distance, they were obtained from the large quantities of dirt samples that were collected during the Bluefish Cave I excavation and later water-screened and processed. If my memory serves me right, they were found to occur mostly (?) in the upper units of the deposit which could well correspond in terms of age to the time range of the "catastrophic" event under discussion. As for size, all I can say (again from memory) is that they were in the -1mm range, i.e., very-micro-glassy-beads. After asking an uninterested geologist, I just ended up calling them "tektites" and left it at that. I had other things to do. In other words, no analysis has been done.

Jacques

From such throwaways are the pearls of serendipity discovered! Sounds to me, Jacques, like you should get on your bike to the Canadian Museum of Civilzation & find that anonymous drawer, toute suite!

Ross Macfarlane :-)

Ross,

Thanks for the moral support. It's very possible that someone will eventually develop an interest in "my spherules". The first problem I would have with this is that I wouldn't want them to be used as support for a grand, catastrophic explanation in which I do not believe. Another problem is that for me to retrieve them would mean that I would have to deal with a very aggravating, Kafkaesque Museum bureaucracy that is clearly more interested in self-serving management, than in actual research. Finally, getting on my bike is presently out of the question. I busted my left knee two weeks ago.

Best,

Jacques


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine December 23, 2007, 01:02:25 PM
Hi Jacques, all -

In the cases of impacts with ice sheets, the craters will melt.

E.P. Grondine
Man and Impact in the Americas



: Re: Spherule attack and the demise of Clovis!
: AWSX December 23, 2007, 06:03:49 PM
The lack of an impact crater is a serious weakness in the theory. However there are examples of some kind of cosmic event that did not leave a crater such as Tunguska. This news release from Sandia Labs could lend some support for the theory but for a continent wide extinction event multiple impactors would be required.

http://www.sandia.gov/news/resources/releases/2007/asteroid.html (http://www.sandia.gov/news/resources/releases/2007/asteroid.html)


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine December 28, 2007, 12:14:30 PM
Based on comparison with more recent events, it appears that  the dust veil from the impacts at 10,900 BCE was probably sufficient to cause climate collapse.

My current working hypothesis is that fast neutrons and fast protons are released in large hyper-velocity impacts, the former responsible for the spikes in C14 seen in the INTCAL98 chart.

E.P. Grondine
Man and Impact in the Americas


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 03, 2008, 03:52:19 PM
Dr. Firstone's agu abstract on the iron impacts:
http://ie.lbl.gov/mammoth/impact.html

and even better, his poster:
http://ie.lbl.gov/mammoth/AGUSF_poster_2.gif

This looks to me like 2 separate iron impacts, one in Alaska about 32,500 BCE,
another in Siberia ca. 24,000 BCE.

These are different than the cometary impact(s) at 10,900 BCE - the impact that Kenneth  evidenced with the other impactites, and that it appears the First Peoples here remembered.

E.P. Grondine
Man and Impact in the Americas



: Re: Spherule attack and the demise of Clovis!
: trehinp January 04, 2008, 03:03:07 AM
Thanks E.P.,

Are you aware of similar research conducted eslewhere in the world?

Siberia with all its well preserved mammoths remains, could be a place (a large one by the way) where to look...

If similar observaions on micro meteorites were to be confirmed elsewhere, it would probably influence the way we interpret the impact of prehistoric major events on various environmental conditions which in turn influenced human evolution, on an individual basis as well as on a group basis.

Looking forward to other info on this...

Paul


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 09, 2008, 09:39:46 PM
Hi Paul -

I was up at the Archaeological Institute of America meeting last weekend in Chicago pitching my book "Man and Impact in the Americas" (available through amazon.com if the site is finally working now).  I met exactly 1 person who had seen the National Geographic Special on comet impact and the extinction of the mammoth, and she was not an archaeologist but a suburban woman doing the town with her family for the weekend.

The results at SEAC (South East Archaeological Conference) in Knoxville were marginally better, with 1 excavator of a Clovis site fully aware, and everyone else at that paleo session extremely sceptical, and baffled by  the discontinuities in their data (having a hard time accepting that comet and asteroid impacts happen...)

It's pretty damn discouraging. Right now, I'm pretty certain my book will do well after I'm dead....

Before 2004, Benny Peiser ran an email service (the Cambridge Conference) which was devoted to paleoclimatology and impact, but at the beginning of 2004 he started in on global warming scepticism, leaving the impact community in a lurch.

So who is working in the field?

As near as I know now, in the US you have the Impact Field Studies Group.  Out of Australia Ted Bryant coordinates to some extent the impact mega-tsunami researchers world wide. Here in the US, NOAA awareness is nil; same for Woodshole.

The USGS is running some field studies, in particular coastal cores.

NASA money is lowering than what the House and Senate have told Griffin to spend.

Internationally, maybe U. New Brunswick in Canada for craters;  CNRS sponsored Dr. Courty's work at Tel Leilan years ago, don't know of any current work, as in general the mideast is too dangerous for field work; the Russians and Italians continue work on the Tunguska impact. As far as paleo or archaic work goes,  Kenneth heads up the end Clovis researchers here in the US; Firestone has people looking for the 2 iron impactors indicated by the peppered fossil remains, and I'm hoping private sector meteorite hunters are at it as well; LuAnn Becker at U Wash. and Dr. Poreda at U. Rochester analyze samples, Schultz continues work in South America; Masse is finally being published in the UK; Snow in New Zealand has passed on; if anyone else is out there, I don't know, or can't remember. Benny moved on to global warming scepticism so there's no clearinghouse now, and I've had a stroke.

Then you have the multitude of cranks trying to scare people out of their wits and sell them utter nonsense...

By the way, I think there's 2 megatsunami for southeast asia, one at 120,000 BCE, one at 240,000 BCE, caused by massive landslides in the Hawaian isles.

I don't know what Chinese researchers are up to, as the Cambridge Conference is now devoted to global warming scepticism.

India has a team of ethnographers (recently published works), and a some field geologists working impact, and good for them for  funding this work. Mohenjo Daro is a very important site for impact studies, with a large crater nearby.

I think maybe Australia has some field geologists looking at craters in the outback.

The Earth will be encountering the debris stream of Comet Schwassmann Wachmann 3 in 2022, and based on recent impacts (Rio Curaca1930, Rupnini 1935, Moss, 2006 ) I expect a 5 kiloton explosion (30 meter fragment) somewhere. 7 out of 10 says over the ocean; 1 out of 10 says a cornfield somewhere; 1 out of 10 says a park or forest...

And then there's this book "Man and Impact in the Americas".

Hope this helps.






: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 18, 2008, 12:52:17 PM
Hi Paul -

My apologies for leaving out the Brazilian team working on the Campo de Cielo impact:

http://www.fcaglp.unlp.edu.ar/~sixto/arqueo/w-6-ing.htm

Since Benny took the Cambridge Conference over to global warming scepticism, we've been left without a clearing house.

E.P. Grondine
Man and Impact in the Americas
(a damned fine book, if I do say so myself)


: Re: Spherule attack and the demise of Clovis!
: trehinp January 18, 2008, 06:45:34 PM
Thanks E.P.,

Since I'm not a specialist in this domain I won't make any comment but I will be interested by the conclusions of all these researches.

The impact of such catastrophic events on human biological and cultural development must have been awsome...

Thanks for keeping us informed.

Paul


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 20, 2008, 02:22:30 PM
Hi Paul -

The effects WERE awesome. Though the human mind has problems dealing with this kind of news, these effects are also undeniable.

You may have noticed that with the exception of Peiser, Masse, and Kenneth et al., the researchers are geologists, physicists, astronomers, paleoclimatologists.  Do you have any idea of how badly anthropology can be done by geologists, physicists, and astronomers?  [Well, it's just a little worse than that done by one veteran space journalist.]

What we have here is a MAJOR force on human development that is generally unrecognized within the anthropological community. Thus this development in the field of anthropology is wide open for whoever gets there first with the most.  Included is every aspect of every people and every culture that ever was.

The price of admission is working alone unfunded while surrounded by sceptics, and at the same time dealing with various nuts, both of the Earth and Space variety.  That's alongside all the normal problems such as racism, nationalism, data ambiguity, irregular data recovery, data bias, and the usual limits in tools.   







: Re: Spherule attack and the demise of Clovis!: New Evidence
: E.P. Grondine November 18, 2008, 10:15:07 AM
Hi Jacques, all -

Forwarded from the Cambridge Conference:

13) YDB/CLOVIS COMET AT AGU

Dear Benny:

I am writing to share the news about the discovery of billions of diamonds per cm3 associated with the proposed Younger Dryas impact event, or "Clovis Comet," as it is sometimes called. Data on the discovery will be presented on December 15-16 at the American Geophysical Union's annual Fall Meeting in San Francisco. On December 16, there will be 4 talks (http://www.agu.org/cgi-bin/sessions5?meeting=fm08∂=PP23D&maxhits=400), and the day before, on December 15, there will be 8 poster presentations (http://www.agu.org/cgi-bin/sessions5?meeting=fm08∂=PP13C&maxhits=400  - Scroll down to PP13C-1469 through 1477). As you and your readers may remember, data on about a dozen other lines of impact evidence were presented to AGU at the Acapulco Joint Assembly in 2007. Since then, the hypothesis has created considerable controversy.

The lead presentation will reveal the discovery of all three diamond allotropes (cubic diamond, lonsdaleite, and n-diamond) in the YDB impact layer, dating to the Younger Dryas onset at 12.9 ka (as well as the new discovery of lonsdaleite and n-diamonds in the KT boundary). The YDB diamonds are distributed broadly across N America and NW Europe at 15 sites spanning 9,000 km or 23 percent of Earth's circumference. N-diamonds and lonsdaleite, or hexagonal diamond, do not co-occur with terrestrial diamonds, but are found in meteorites. Lonsdaleite is found on Earth only in association with known ET impacts, and thus, is a definitive impact indicator. No diamonds have ever been detected in sediments above or below the YD impact layer.

Some critics have suggested that all the inferred impact material is nothing more than typical meteoritic ablation products and that the indicators rained down from the heavens non-catastrophically over time. This hypothesis is refuted by the presence of millions of diamonds inside single carbon spherules that formed rapidly from charred tree sap. Our research, which has resulted in a patent application for a new process to create diamonds, indicates that they could have only formed during the extraordinarily high temperatures and pressures that existed during an impact. The "cosmic rain" was heavy and far from gentle.
 
I have also placed a PDF of them on my website here:  http://www.georgehoward.net/finalAGUabstracts.pdf

Kind regards.

George A. Howard |  Partner
Restoration Systems, LLC
1101 Haynes Street, Suite 211
Raleigh N.C. 27604
www.restorationsystems.com
www.georgehoward.net

I think that explains all those corpses Hibben saw piled up. And explains some of those strange tales
some of the peoples here in North America told.

E.P. Grondine
Man and Impact in the Americas
(a damned fine book, if I do say so myself, and paleo forum participants can write me off list for personally signed copies  for a special low price. My book has hundreds of pages of small type filled with typos and not enough pictures, and if that were not enough, in addition it has a correction sheet is pasted inside its front cover!)







: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine December 16, 2008, 08:36:54 AM
http://www.theprogressortimes.com/news/articles.asp?articleID=10335

A well excavated and well dated one inch thick layer of impact products near Sandusky, Ohio:

Did extraterrestrial event alter the course of history?

BY DAN REINHART

For years Sheriden Cave, west of Carey, has been recognized as one of the foremost archaeological sites in the Americas, if not the world. At the cave scientists have unearthed extinct animal species and artifacts that have been undisturbed since the last ice age.

Recently, however, excavations by Dr. Ken Tankersley, an archaeologist from the University of Cincinnati, have uncovered evidence that indicate an extraterrestrial event some 13,000 years ago may have permanently altered the course of history in the Americas and possibly the whole world. As a result the cave will be featured in several upcoming documentaries on the Discovery Channel and the History Channel.

"The most interesting county."

"Wyandot County is the most interesting county in Ohio," Tankersley told a group gathered at Woody's restaurant in Upper Sandusky Dec. 4. Tankersley was the guest speaker at the "First Citizens Presents" breakfast and he has appeared in documentaries on a host of television channels including PBS, Discovery, National Geographic, Animal Planet and others. He also worked on a film with the late Steve Irwin.

Tankersley said that besides being shaped in a square because it was the last Indian reservation in the State of Ohio, Wyandot County also contains, at Sheriden Cave, a "complete, uninterrupted archaeological sequence spanning the 13,000 years since the last ice age."

Tankersley said he first became interested in the area in the early 1990s. He was in New York at the time and a friend who was doing some work at Sheriden Cave told him that excavations there had uncovered fossils from a number of extinct species – including the short-faced bear – that previously had never been found in the State of Ohio.

National attention.

Excavation at the cave also uncovered a flaked stone artifact that was dated back some 13,000 years to an ancient people known as the Clovis culture. Tankersley said that although there are other Clovis sites in the world, Sheriden Cave is the only site where animal fossils can be found right alongside the flaked stone tools ancient people of the same time period made. For that reason Sheriden Cave became a major archaeological discovery.

Tankersley said he originally became involved in Sheriden Cave excavations because remnants of an ancient peccary had been found there. He came to look at the site and after finding a number of artifacts he wrote to the National Science Foundation who, with the help of the Hendricks family, who own the cave, agreed to sponsor an excavation there in 1996.

Tankersley eventually found a number of bones that had been carved into tools and a fluted Clovis point among the remains of various extinct animals. He noted that some of the ancient bones found in Sheriden Cave are fresher than you might find on a modern road-kill. "It's absolutely incredible," he said. "They're abundant and very well preserved."

The Black Mat.

As the excavations continued workers began to uncover a lot of burnt bones. Tankersley said that at first no one paid very much attention to them but eventually questions were raised about how the bones got burned. He said it was obvious that if primitive man had cooked an animal so much that the bones were burned, no one would have wanted to eat the meat. They concluded that the primitive people must have thrown the bones in the fire after they were done eating. But there was no evidence of hearths in the cave. "Why were these animal bones so severely burned?" Tankersley asked.

As excavators searched for an answer to the burnt bones they began to notice an inch-thick layer of earth in the sediment throughout the cave that was black. Scientists were able to obtain 30 radiocarbon dates that indicated the layer of burned material, or "Black Mat," was about 13,000 years old. It dated to about the same time period that Clovis man and many of the mega-beasts disappeared. (The radiocarbon dates have made Sheriden Cave one of only 12 securely dated Clovis sites in the world.)

A new theory takes shape.

With the help of a man named Alan West, Tankersley found that Black Mat layers have been discovered in other late Ice Age sites across the country from the Carolinas to Texas and even into Canada. In each instance the Black Mat of burnt material dates back to the same time period. Furthermore, the Black Mats contain an abundance of micrometeorites. Tankersley said that soil from the Black Mat in Sheriden Cave contains so many magnetic, microscopic meteorites that he can wave a child's magnet across samples of the soil and cover the magnet with them.

Tankersley took the Black Mat material to the University of Cincinnati and magnified it 10,000 times through an electron microscope. He found it was also filled with microscopic "detonation diamonds." He said the majority of the (microscopic) diamonds in the Black Mat are extraterrestrial.

Tankersley pointed out that when asteroids and meteorites explode over the earth they create diamonds. He says the ones at Sheriden Cave are either directly from objects from outer space or they are the result of a major explosion over the earth – like a comet exploding over organic material that compressed it and made diamonds. Tankersley said it is increasingly likely that an asteroid or meteor is the reason for the disappearance of the Clovis people and the mega-beasts 13,000 years ago.

Tankersley said the evidence indicates that the catastrophic event may not have wiped out Clovis man and the mega mammals completely, but life definitely changed and creatures that survived the event had to find a way to exist in a changed environment. For example, there wasn't a lot of food around and since the mega mammals required a lot of food to survive, they had to adapt or die. He said some of the mega mammals became smaller.

Although evidence indicates that an asteroid created the Black Mat, no one has ever found a crater to prove where the event originated. Some scientists believe that Hudson Bay may actually be the crater.

13,000 years later.

Tankersley said that the implications for us in the 21st century are sobering in that the impact of another history-altering asteroid with earth is not a question of "if" it will happen, but "when" it's going to happen next.

Tankersley said that some of the people from Wyandot County who made his work at Sheriden Cave possible include Keith Hendricks and his father Richard, Kate Orians who wrote a number of stories about Tankersley and his work for The Progressor-Times and Dale Stansbery of the Ohio Archaeological Council.

Tankersley also noted that the latest discoveries made at Sheriden Cave will be featured in a film on the Discovery Channel in December and another film on the History Channel this spring.

E.P. Grondine
Man and Impact in the Americas
(Hundreds of pages of small type filled with typos, not enough illustrations, and as if this were not enough,
a correction sheet pasted inside the cover of every signed copy. Write me off list for signed copies at a special
low price.)


: Re: Spherule attack and the demise of Clovis!
: trehinp January 05, 2009, 04:22:42 AM
More info on this, perhaps...

Six North American Sites Hold 12,900 Year-old Nanodiamond-rich Soil
Source: University of Oregon    28-Dec-2008
Newswise — Abundant tiny particles of diamond dust exist in sediments dating to 12,900 years ago at six North American sites, adding strong evidence for Earth’s impact with a rare swarm of carbon-and-water-rich comets or carbonaceous chondrites, reports a nine-member scientific team.
Click here for more (http://www.newswise.com/articles/view/547746/?sc=dwhn)

I hope this will help the debate...

Yours.

Paul


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 06, 2009, 12:55:47 PM
The debate? Note Tankersley's site above.

Note the difference between the public reporting of Firestone and Kenneth's work, versus the lack of news stories on
Tankersley's excavations.

The politics of impact research have been and are strange. In the US, research money and publication was controlled by Dr. David Morrison, a pioneering impact researcher, who has rather tenaciously held that asteroids hit 95%, and comets hit 5%. Thus work on the recent comet impacts was limited.

Firestone had an independent source of funding, and published through geological channels, hence the work on comet impact got done.

The archaeological community itself has been resistant to the idea of recent comet and asteroid impacts. Why this is
is fascinating in and of itself, and perhaps it is better explained by sociology and psychology. Archaeologists had earlier come up with other explanations for discontinuities, including the mega-fauna extinction, and will hold to them even if new definitive data comes in. Peoples' early accounts of these were dismissed as myths.

Psychologically, massive numbers of deaths from asteroid and comet impact is a tough thing to accept.

E.P. Grondine
Man and Impact in the Americas (not too bad a book - hundreds of pages of small type filled with typos, not enough pictures, and a correction sheet pasted inside its front cover.)








: Re: Spherule attack and the demise of Clovis!
: AWSX January 09, 2009, 10:25:23 AM
Spherules seem to be turning up everywhere. This discovery from the Greenland icecore seems to indicate an impact in 536AD at the start of the Dark Ages. http://www.agu.org/cgi-bin/SFgate/SFgate?&listenv=table&multiple=1&range=1&directget=1&application=fm08&database=%2Fdata%2Fepubs%2Fwais%2Findexes%2Ffm08%2Ffm08&maxhits=200&=%22PP41B-1454%22


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine January 09, 2009, 10:13:00 PM
Spherules seem to be turning up everywhere. This discovery from the Greenland icecore seems to indicate an impact in 536AD at the start of the Dark Ages. http://www.agu.org/cgi-bin/SFgate/SFgate?&listenv=table&multiple=1&range=1&directget=1&application=fm08&database=%2Fdata%2Fepubs%2Fwais%2Findexes%2Ffm08%2Ffm08&maxhits=200&=%22PP41B-1454%22

Impacts were not suspected earlier, but rather simply a cometary dust veil from Comet Encke. David Keys attributed the climate collapse to volcanism, but that did not seem to work:
http://abob.libs.uga.edu/bobk/ccc/ce082202.html 
- my 2002 impossibly convoluted survey of impossibly convoluted times

The climate collapse ended Hopewell Hopewell in North America - the survivors assimilated with the Algonquin stream of the Shawnee people, who were forced down from the north by this.

E.P. Grondine
Man and Impact in the Americas


: Possible impact site
: E.P. Grondine March 20, 2009, 11:23:03 PM
Hi all -

The prediction was:
http://www.dispatch.com/live/content/local_news/stories/2008/07/21/comet.ART_ART_07-21-08_B1_P5APQ1P.html

and a local person spotted this:
http://www.meridianbooster.com/ArticleDisplay.aspx?e=1484183

Is it one of the main impact points? we'll see...

E.P. Grondine
Man and Impact in the Americas


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine March 26, 2009, 03:21:22 PM
Hello everyone -

For a while, objections were raised that the spherules and nano-diamonds were just normal
accumulations around "wadis" of meteoritic entry produts. This "rationalization" (and rationalization it was,
as nano-diamonds are not regularly produced by simple meteorite entry) had now been put to an end:

http://www.pbs.org/wgbh/nova/clovis/

with the recovery of well dated impactites from otherwise sterile Greenland ice deposits:
http://www.pbs.org/wgbh/nova/clovis/

What really happened? Well, here are some of the first people's accounts:

http://forum.palanth.com/index.php/topic,1093.0.html

E.P. Grondine
Man and Impact in the Americas (despite all of its flaws, a pretty all right book, in my own opinion).



: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine March 26, 2009, 08:06:17 PM
NOVA also has this summary of the debate:


E.P. Grondine
Man and Impact in the Americas


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine September 03, 2009, 02:46:27 PM
Via Leroy Ellenberger...

History Channel has premiered a subject program about impacts on Earth from meteors,
asteroids, comets and space debris:

 <http://www.history.com/shows.do?action=detail&episodeId=481956>

The program will be re-broadcast Sunday, Sept. 6 at 7 p.m.
EDT, Tuesday, Sept. 15 at 8 p.m. EDT and Wed. Sept. 16
at midnight EDT. Check your local schedule.

...
...A surprising subject was the work of Ohio archaeologist Ken Tankersley (Kent State Univ.)
at Sheriden Cave in Ohio where he and his team have been excavating remains of
Pleistocene mega-fauna and Clovis artifacts from the horizon at 12,900 B.P.

The FACT of the Younger-Dryas impact at this time was practically implicit in the program.


: Re: Spherule attack and the demise of Clovis!
: Jacques Cinq-Mars September 05, 2009, 11:22:14 PM
Via Leroy Ellenberger...

History Channel has premiered a subject program about impacts on Earth from meteors,
asteroids, comets and space debris:

 <http://www.history.com/shows.do?action=detail&episodeId=481956>

The program will be re-broadcast Sunday, Sept. 6 at 7 p.m.
EDT, Tuesday, Sept. 15 at 8 p.m. EDT and Wed. Sept. 16
at midnight EDT. Check your local schedule.

...A surprising subject was the work of Ohio archaeologist Ken Tankersley (Kent State Univ.)
at Sheriden Cave in Ohio where he and his team have been excavating remains of
Pleistocene mega-fauna and Clovis artifacts from the horizon at 12,900 B.P.

The FACT of the Younger-Dryas impact at this time was practically implicit in the program.

Thanks for passing this on. I only have one question about the "FACT" you mention. Yes, but so what?


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine September 06, 2009, 03:39:53 PM
Thanks for passing this on. I only have one question about the "FACT" you mention. Yes, but so what?

A pleasure to pass it on, Jacques, and thank you for keeping the topic open for discussion even when the hypothesis was widely condemned and ridiculed. The FACT wording was Leroy Ellenbreger's comment; he's been at this longer than I have, so you can imagine his relief.

"Yes, but so what?"  At this point, I'm too tired to say. What do you think?

E.P. Grondine
Man and Impact in the Americas


: Re: Spherule attack and the demise of Clovis!
: E.P. Grondine October 13, 2009, 04:09:48 PM
The effect in Europe and South America:

2009 FALL AGU San Francisco, CA
Field-Analytical approach of land-sea records for elucidating the Younger Dryas Boundary syndrome
SECTION/FOCUS GROUP: Paleoceanography and Paleoclimatology (PP)
SESSION: Younger Dryas Boundary: Extraterrestrial Impact or Not? (PP15)
AUTHORS (FIRST NAME, LAST NAME): Thierry Ge1, MARIE-AGNES MICHELE COURTY2, Francois Guichard3
INSTITUTIONS (ALL):
1. Geoarcheology, INRAP, Pessac, France.
2. Prehistory -IPHES-ICREA, CNRS-MNHN, Tarragona, Spain.
3. Paleoocenography, CNRS-CEA UVSQ, Gif-sur-Yvette, France.

Linking lonsdaleite crystals, carbon spherules and diamond polymorphs from the North American dark layers at 12.9 cal yr B.P. to a cosmic event has questioned the nature and timing of the related impact processes. A global signal should trace the invoked airshocks and/or surface impacts from a swarm of comets or carbonaceous chondrites.

Here we report on the contextual analytical study of debris fall events from three reference sequences of the Younger Dyras period (11-13 ka cal BP):

(1) sand dune fields along the French Atlantic coast at the Audenge site;
(2) A 10 m record of detrital/bioorganic accumulation in the southern basin of the Caspian Sea with regular sedimentation rate (0.1 to 3 mm per year) from 14 to 2-ka BP cal;
(3) the Paijan sequence (Peruvian coastal desert) offering fossiliferous fluvial layers with the last large mammals and aquatic fauna at 13 ka BP sealed by abiotic sand dunes.

The three sequences display one remarkable layer of exogenous air-transported microdebris that is part of a complex time series of recurrent fine dust/wildfire events. The sharp debris-rich microfacies and its association to ashes derived from calcination of the local vegetation suggest instantaneous deposition synchronous to a high intensity wildfire. The debris assemblage comprises microtektite-like glassy spherules, partly devitrified glass shards, unmelted to partly melted sedimentary and igneous clasts, terrestrial native metals, and carbonaceous components. The later occur as grape-clustered polymers, vitrified graphitic carbon, amorphous carbon spherules with a honeycomb pattern, and green carbon fibres with recrystallized quartz and metal blebs. Evidence for high temperature formation from a heterogeneous melt with solid debris and volatile components derived from carbonaceous precursors supports an impact origin from an ejecta plume. The association of debris deposition to total firing would trace a high energy airburst with surface effects of the fireball. In contrast, microfacies and debris composition of the recurrent fine dust/wildfire events would trace a series of a low energy airburst. Their record is expressed in the Audenge sequence by a series of water-laid laminae of charred pine residues formed of carbonaceous spherules wrapped by carbonaceous polymers that includes lonsdaleite crystals as detected by high resolution in situ micro-Raman analysis. This association suggests recurrent flash forest wildfires ignited by hot spray of carbon-rich debris, followed by heavy snow falls. The record from the Peruvian desert suggests a possible linkage between the repeated debris fall/wildfires during the Younger Dryas and the following irreversible aridity along the Peruvian cost. In contrast the Caspian record of the Younger Dryas period indicates more gradual changes, possibly buffered by the hydrological functioning of the Caspian sea in a complex region. The Audenge context offers the amplified signal needed to understand at local to global scales the spatio-temporal pattern of impact-airburst events.

KEYWORDS: [4901] PALEOCEANOGRAPHY / Abrupt/rapid climate change, [1029] GEOCHEMISTRY / Composition
of aerosols and dust particles, [4924] PALEOCEANOGRAPHY / Geochemical tracers, [5420] PLANETARY
SCIENCES: SOLID SURFACE PLANETS / Impact phenomena, cratering.
Previously Presented Material: Original results, never presented, never published


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