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Catastrophe: Which Ancient Disaster was the One to Destroy Atlantis?

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Adam Hawthorne
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« Reply #15 on: September 16, 2009, 11:41:11 pm »

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« Reply #16 on: September 16, 2009, 11:41:29 pm »

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« Reply #17 on: September 16, 2009, 11:41:50 pm »

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« Reply #18 on: September 16, 2009, 11:42:03 pm »

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« Reply #19 on: September 16, 2009, 11:42:23 pm »

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« Reply #20 on: September 16, 2009, 11:42:37 pm »

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« Reply #21 on: September 16, 2009, 11:43:53 pm »

Site provides evidence for ancient comet explosion

JOEY HOLLEMAN; McClatchy Newspapers Published: October 7th, 2007 01:00 AM

 
 
 
COLUMBIA, S.C. – For the second time in less than a decade, a South Carolina river bluff holds evidence pointing to a theory with history-rewriting potential.
Microscopic soil particles from the Topper site near Allendale might hold a tiny key to a big theory: that comet-caused explosions wiped out the mammoths and mastodons, prompted the last ice age and decimated the first human culture in North America about 12,900 years ago.

The comet theory first began generating a buzz at an international meeting of geophysicists in Mexico in May. The findings were published this month in the Proceedings of the National Academy of Sciences. They’re about to go mainstream, with a National Geographic Channel segment today. The History Channel will film for a future show at Topper this week.

“People are fascinated by it,” said Allen West, an Arizona geophysicist and one of the leaders of the comet team, who’s speaking Wednesday at USC. “It has diamonds and giant elephants and Indians. Any new catastrophe theory that comes along gets plenty of attention.”

The new theory holds that a comet broke apart in the atmosphere above what is now eastern North America, producing explosions and wildfires as the pieces smashed into the surface.

Scientists, led by Richard Firestone of the Lawrence Berkeley National Laboratory in Berkeley, Calif., took soil samples from throughout North America and in Belgium. In a layer dating to about 12,900 years ago, they found high levels of iridium, nanodiamonds and glasslike carbon that could have been caused by a comet explosion and subsequent fires.

The Topper site, on the Savannah River, provided compelling evidence, in part because of earlier findings by Al Goodyear of the S.C. Institute of Archaeology and Anthropology at USC.

Goodyear drew international attention in 2004 when stone points found at Topper that apparently were sharpened by humans (Clovis points) were carbon dated to nearly 50,000 years ago. That put human beings in North America thousands of years earlier than thought. For generations, scientists have thought the first humans arrived 13,000 years ago via a land bridge from Asia.

Goodyear’s work at Topper, along with similar finds in Brazil and Chile, prompted scientific reconsideration of when humans arrived in North America. It also led to skepticism by scientists who didn’t buy Goodyear’s theory. In that regard, he found kindred spirits in the comet group.

“This is a pretty wild theory,” Goodyear said with a chuckle. “I’m glad I’m not doing this one.”

He welcomed West to dig at Topper. At the same depth as Topper’s undeniable Clovis artifacts, West found high concentrations of iridium, nanodiamonds and glasslike carbon.

West’s findings prompted Goodyear to do his own study on the disappearance of Clovis points. These stone tools are found throughout North America only in soil dating back about 13,000 years or more.

Not long after that, a different style of points began showing up from people scientists have dubbed the Redstone culture.

Goodyear’s recent study found there were four times as many Clovis points as Redstone points at similar sites. That would indicate a huge population drop from the Clovis to Redstone cultures, possibly caused by some natural catastrophe.


http://www.thenewstribune.com/news/nationworld/story/173177.html
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« Reply #22 on: September 16, 2009, 11:45:00 pm »

Ancient Crash, Epic Wave




The Fenambosy chevron, one of four near the tip of Madagascar, is 600 feet high and three miles from the ocean.

At the southern end of Madagascar lie four enormous wedge-shaped sediment deposits, called chevrons, that are composed of material from the ocean floor. Each covers twice the area of Manhattan with sediment as deep as the Chrysler Building is high.

On close inspection, the chevron deposits contain deep ocean microfossils that are fused with a medley of metals typically formed by cosmic impacts. And all of them point in the same direction — toward the middle of the Indian Ocean where a newly discovered crater, 18 miles in diameter, lies 12,500 feet below the surface.

The explanation is obvious to some scientists. A large asteroid or comet, the kind that could kill a quarter of the world’s population, smashed into the Indian Ocean 4,800 years ago, producing a tsunami at least 600 feet high, about 13 times as big as the one that inundated Indonesia nearly two years ago. The wave carried the huge deposits of sediment to land.

Most astronomers doubt that any large comets or asteroids have crashed into the Earth in the last 10,000 years. But the self-described “band of misfits” that make up the two-year-old Holocene Impact Working Group say that astronomers simply have not known how or where to look for evidence of such impacts along the world’s shorelines and in the deep ocean.

Scientists in the working group say the evidence for such impacts during the last 10,000 years, known as the Holocene epoch, is strong enough to overturn current estimates of how often the Earth suffers a violent impact on the order of a 10-megaton explosion. Instead of once in 500,000 to one million years, as astronomers now calculate, catastrophic impacts could happen every 1,000 years.

The researchers, who formed the working group after finding one another through an international conference, are based in the United States, Australia, Russia, France and Ireland. They are established experts in geology, geophysics, geomorphology, tsunamis, tree rings, soil science and archaeology, including the structural analysis of myth. Their efforts are just getting under way, but they will present some of their work at the American Geophysical Union meeting in December in San Francisco.

This year the group started using Google Earth, a free source of satellite images, to search around the globe for chevrons, which they interpret as evidence of past giant tsunamis. Scores of such sites have turned up in Australia, Africa, Europe and the United States, including the Hudson River Valley and Long Island.

When the chevrons all point in the same direction to open water, Dallas Abbott, an adjunct research scientist at Lamont-Doherty Earth Observatory in Palisades, N.Y., uses a different satellite technology to look for oceanic craters. With increasing frequency, she finds them, including an especially large one dating back 4,800 years.

So far, astronomers are skeptical but are willing to look at the evidence, said David Morrison, a leading authority on asteroids and comets at the NASA Ames Research Center in Mountain View, Calif. Surveys show that as many as 185 large asteroids or comets hit the Earth in the far distant past, although most of the craters are on land. No one has spent much time looking for craters in the deep ocean, Dr. Morrison said, assuming young ones don’t exist and that old ones would be filled with sediment.

Astronomers monitor every small space object with an orbit close to the Earth. “We know what’s out there, when they return, how close they come,” Dr. Morrison said. Given their observations, “there is no reason to think we have had major hits in the last 10,000 years,” he continued, adding, “But if Dallas is right and they find 10 such events, we’ll have a real contradiction on our hands.”

Peter Bobrowsky, a senior research scientist in natural hazards at the Geological Survey of Canada, said “chevrons are fantastic features” but do not prove that megatsunamis are real. There are other interpretations for how chevrons are formed, including erosion and glaciation. Dr. Bobrowsky said. It is up to the working group to prove its claims, he said.

William Ryan, a marine geologist at the Lamont Observatory, compared Dr. Abbott’s work to that of other pioneering scientists who had to change the way their colleagues thought about a subject.

“Many of us think Dallas is really onto something,” Dr. Ryan said. “She is building a story just like Walter Alvarez did.” Dr. Alvarez, a professor of earth and planetary sciences at the University of California, Berkeley, spent a decade convincing skeptics that a giant asteroid wiped out the dinosaurs 65 million years ago.

http://www.iht.com/articles/2006/11/14/healthscience/web.1114meteor.php?page=1
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« Reply #23 on: September 16, 2009, 11:45:26 pm »

Ted Bryant, a geomorphologist at the University of Wollongong in New South Wales, Australia, was the first person to recognize the palm prints of mega-tsunamis. Large tsunamis of 30 feet or more are caused by volcanoes, earthquakes and submarine landslides, he said, and their deposits have different features.

Deposits from mega-tsunamis contain unusual rocks with marine oyster shells, which cannot be explained by wind erosion, storm waves, volcanoes or other natural processes, Dr. Bryant said.

“We’re not talking about any tsunami you’re ever seen,” Dr. Bryant said. “Aceh was a dimple. No tsunami in the modern world could have made these features. End-of-the-world movies do not capture the size of these waves. Submarine landslides can cause major tsunamis, but they are localized. These are deposited along whole coastlines.”

For example, Dr. Bryant identified two chevrons found over four miles inland near Carpentaria in north central Australia. Both point north. When Dr. Abbott visited a year ago, he asked her to find the craters.

To locate craters, Dr. Abbott uses sea surface altimetry data. Satellites scan the ocean surface and log the exact height of it. Underwater mountain ranges, trenches and holes in the ground disturb the Earth’s gravitational field, causing sea surface heights to vary by fractions of an inch. Within 24 hours of searching the shallow water north of the two chevrons, Dr. Abbott found two craters.

Not all depressions in the ocean are impact craters, Dr. Abbott said. They can be sink holes, faults or remnant volcanoes. A check is needed. So she obtained samples from deep sea sediment cores taken in the area by the Australian Geological Survey.

The cores contain melted rocks and magnetic spheres with fractures and textures characteristic of a cosmic impact. “The rock was pulverized, like it was hit with a hammer,” Dr. Abbott said. “We found diatoms fused to tektites,” a glassy substance formed by meteors. The molten glass and shattered rocks could not be produced by anything other than an impact, she said.

“We think these two craters are 1,200 years old,” Dr. Abbott said. The chevrons are well preserved and date to about the same time.

Dr. Abbott and her colleagues have located chevrons in the Caribbean, Scotland, Vietnam and North Korea, and several in the North Sea.

Hither Hills State Park on Long Island has a chevron whose front edge points to a crater in Long Island Sound, Dr. Abbott said. There is another, very faint chevron in Connecticut, and it points in a different direction.

Marie-Agnès Courty, a soil scientist at the European Center for Prehistoric Research in Tautavel, France, is studying the worldwide distribution of cosmogenic particles from what she suspects was a major impact 4,800 years ago.

But Madagascar provides the smoking gun for geologically recent impacts. In August, Dr. Abbott, Dr. Bryant and Slava Gusiakov, from the Novosibirsk Tsunami Laboratory in Russia, visited the four huge chevrons to scoop up samples.

Last month, Dee Breger, director of microscopy at Drexel University in Philadelphia, looked at the samples under a scanning electron microscope and found benthic foraminifera, tiny fossils from the ocean floor, sprinkled throughout. Her close-ups revealed splashes of iron, nickel and chrome fused to the fossils.

When a chondritic meteor, the most common kind, vaporizes upon impact in the ocean, those three metals are formed in the same relative proportions as seen in the microfossils, Dr. Abbott said.

Ms. Breger said the microfossils appear to have melded with the condensing metals as both were lofted up out of the sea and carried long distances.

About 900 miles southeast from the Madagascar chevrons, in deep ocean, is Burckle crater, which Dr. Abbott discovered last year. Although its sediments have not been directly sampled, cores from the area contain high levels of nickel and magnetic components associated with impact ejecta.

Burckle crater has not been dated, but Dr. Abbott estimates that it is 4,500 to 5,000 years old.

It would be a great help to the cause if the National Science Foundation sent a ship equipped with modern acoustic equipment to take a closer look at Burckle, Dr. Ryan said. “If it had clear impact features, the nonbelievers would believe,” he said.

But they might have more trouble believing one of the scientists, Bruce Masse, an environmental archaeologist at the Los Alamos National Laboratory in New Mexico. He thinks he can say precisely when the comet fell: on the morning of May 10, 2807 B.C.

Dr. Masse analyzed 175 flood myths from around the world, and tried to relate them to known and accurately dated natural events like solar eclipses and volcanic eruptions. Among other evidence, he said, 14 flood myths specifically mention a full solar eclipse, which could have been the one that occurred in May 2807 B.C.

Half the myths talk of a torrential downpour, Dr. Masse said. A third talk of a tsunami. Worldwide they describe hurricane force winds and darkness during the storm. All of these could come from a mega-tsunami.

Of course, extraordinary claims require extraordinary proof, Dr. Masse said, “and we’re not there yet.”

Correction: Nov. 16, 2006

An article in Science Times on Tuesday about new research suggesting that a comet or an asteroid may have struck the Indian Ocean 4,800 years ago included an incorrect estimate from researchers for the frequency of such collisions. The current estimate is one impact on the order of a 10-megaton bomb every 1,000 years, not every few thousand years. The article also misstated the name of a state park on Long Island that has a large sand wedge called a chevron, which may indicate that a comet or meteor landed in the ocean nearby. It is Hither Hills, not Heather Hill.

Correction: Dec. 1, 2006

An article in Science Times on Nov. 14 about new research suggesting that a comet or an asteroid may have struck the Indian Ocean 4,800 years ago misspelled the name of a scientist at the Geological Survey of Canada who specializes in natural hazards. He is Peter Bobrowsky, not Bobrowski.

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« Reply #24 on: September 16, 2009, 11:45:56 pm »

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« Reply #25 on: September 16, 2009, 11:47:23 pm »

June 28, 2007
Comet theory collides with Clovis research, may explain disappearance of ancient people


A theory put forth by a group of 25 geo-scientists suggests that a massive comet exploded over Canada, possibly wiping out both beast and man around 12,900 years ago, and pushing the earth into another ice age.


 

University of South Carolina archaeologist Dr. Albert Goodyear said the theory may not be such "out-of-this-world" thinking based on his study of ancient stone-tool artifacts he and his team have excavated from the Topper dig site in Allendale, as well as ones found in Georgia, North Carolina and Virginia.



The tools, or fluted spear points, made by flaking and chipping flint, were used for hunting and made by the Clovis people, who lived 13,100 to 12,900 years ago, and from the Redstone people who emerged afterwards. The two points are distinctly different in appearance, with Redstone points more impressively long and steeple-shaped.



"I saw a tremendous drop-off of Redstone points after Clovis," said Goodyear. "When you see such a widespread decline or pattern like that, you really have to wonder whether there is a population decline to go with it."

For every Redstone point, Goodyear says, there are four or five Clovis points. His findings are leading archaeologists from across North America to reexamine their fluted points, and their inventories are yielding similar results: a widespread decline of post-Clovis points that suggests a possible widespread decline of humans.

 

"What is interesting is that Redstone people came after Clovis people and may have lasted as many centuries as Clovis did, probably even longer, but there are fewer of these Redstone points than Clovis ones," Goodyear said. "That is really odd, because if the Redstone culture simply came right after the Clovis culture you'd expect at least as many Redstone points as Clovis ones. We just don't see that, and the question is why, and what happened to the people who made these tools?"

Archaeologists have long known that the great beasts of the age – the wooly mammoth and mastodon – suddenly disappeared around the same time period (12,900 - 12, 800 years ), but little was known about their demise. It was thought to be the result of over-hunting by Clovis man or climate change associated with a new ice age.

 

The notion that a comet collided with Earth and caused these events was farfetched until recently, when the group of scientists began looking for evidence of a comet impact, which they call the Younger - Dryas Event. They turned to Goodyear and the pristine Clovis site of Topper.

In 2005, Arizona geophysicist Dr. Allen West and his team traveled to Topper in hopes of finding concentrations of iridium, an extra-terrestrial element found in comets, in the layer of Clovis-era sediment.

"They found iridium and plenty of it," said Goodyear. "The high concentrations were much higher than you would normally see in the background of the earth's crust. That tends to be an indicator of a terrestrial impact from outer space."



The researchers also found high iridium concentrations at six other Clovis sites throughout North America, as well as in and along the rims of the Carolina Bays, the elliptically shaped depressions that are home to an array of flora and fauna along South Carolina's coast.

The Younger- Dryas Event suggests that a large comet exploded above Canada, creating a storm of fiery fragments that rained over North America. The fragments could have easily killed the giant mammals of the day, as well as Clovis man.

"No one has ever had a really good explanation for the disappearance of mammoth and mastodon," Goodyear said. "The archaeological community is waking up to the Younger-Dryas Event. It doesn't prove that these Clovis people were affected by this comet, but it is consistent with the idea that something catastrophic happened to the Clovis people at the same time period."

The comet theory dominated the recent annual meetings of the American Geophysical Union held in Mexico. Goodyear's Clovis-Redstone point study and West's research on the comet were featured at the AGU meetings and by the journal, Nature. The comet will be the subject of documentaries featured on the National Geographic Channel and NOVA television late this fall and in early 2008.


--------------------------------------------------------------------------------
The Topper story
Dr. Al Goodyear, who conducts research through the University of South Carolina's S.C. Institute of Anthropology and Archaeology, began excavating Clovis artifacts along the Savannah River in Allendale County in 1984. In 1998, with the hope of finding evidence of a pre-Clovis culture earlier than the accepted 13,100 years, Goodyear began a concerted digging effort on a site called Topper, located on the property of the Clariant Co.

His efforts paid off. Goodyear unearthed blades made of flint and chert that he believed to be the tools of an ice age culture back some 16,000 years or more. His findings, as well as similar ones yielded at other pre-Clovis sites in North America, sparked great change and debate in the scientific community.

Believing that if Clovis and Redstone people thrived near the banks of the Savannah River, Goodyear thought the area could haven been an ideal location for a more ancient culture. Acting on a hunch in 2004, Goodyear dug even deeper down into the Pleistocene Terrace and found more artifacts of a pre-Clovis type buried in a layer of sediment stained with charcoal deposits. Radio carbon dates of the burnt plant remains yielded dates of 50,000 years, which suggested man was in South Carolina long before the last ice age. Goodyear's finding not only captured international media attention, but it has put the archaeology field in flux, opening scientific minds to the possibility of an even earlier pre-Clovis occupation of the Americas.

Since 2004, Goodyear has continued his Clovis and pre-Clovis excavations at Topper. With support of Clariant Corp. and SCANA, plus numerous individual donors, a massive shelter and viewing deck now sit above the dig site to allow Goodyear and his team of graduate students and community volunteers to dig free from the heat and rain and to protect what may be the most significant early-man dig in America.


http://uscnews.sc.edu/ARCH190.html
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« Reply #26 on: September 16, 2009, 11:49:20 pm »

DID A COMET CAUSE A FIRESTORM THAT DEVESTATED NORTH AMERICA 12,900 YEARS AGO?

A REPORT BY ANDREW COLLINS

New evidence has emerged demonstrating that a massive firestorm from space devastated North America some 12,900 years ago, causing unimaginable firestorms, the return of the ice age and a 70 percent destruction of human population, all this according to new results gathered by a team of 25 researchers.

This incredible view of events centred around the end of the geological era known as the Pleistocene was presented last week to a stunned audience at the American Geophysical Union meeting in Acapulco, Mexico. It features also in the latest issue of NEW SCIENTIST magazine (194:2605, 26 May 2007, 8-9), from which this story is taken.

Scientists now believe that the cause of this continental sized cataclysm was a disintegrating comet, which fractured into tiny pieces as it entered the atmosphere from the north or northwest, causing massive explosions and fireballs.

A Continent on Fire

One of the three-main scientists speaking on behalf of the team, Jim Kennett, an oceanographer at the University of California, Santa Barbara, showed striking evidence from several sites of large scale wildfires that torched North America in the wake of the comet break-up. In his words” ‘The whole continent was on fire.’

Evidence comes from a narrow 12,900 year old carbon-rich layer of sediment uncovered at no less than eight sites belonging to the Clovis horizon, as well as from several other sample sites of sediment in North America.

Extraterrestrial Debris

At many of the sites the scientific team have uncovered evidence of extraterrestrial debris, including what they refer to as nanodiamonds, tiny glass-like spherules which form rapidly when molten droplets cool rapidly in the air. They form usually during comet or asteroid impacts. Also discovered at the sites were rare helium-3 molecules, which are known to be more common in deep space than on Earth.

‘You might find some other explanation for these individually,’ said Richard Firestone, a nuclear analytical chemist working at Lawrence Berkeley National Laboratory in California, ‘but taken together, it’s pretty clear that there was an impact.’

He also believs that the obvious culprit is a comet, since the key sediment layers examined thus far have not produced characteristic evidence of high nickel and iridium content, found in connection with asteroid and meteorite impacts, such as that found in connection with the so-called KT Boundary Event suspected of wiping out the dinosaurs some 65 million years ago.

http://www.mysterious-america.net/nacomet.html

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« Reply #27 on: September 16, 2009, 11:49:40 pm »

Obvious Skepticism

Naturally there is going to be wide scale objection to these staggering new theories, which have immense implications in other areas of science and literature, including the reality of Plato’s account of the destruction of Atlantis, which might well preserve some semblance of the comet’s impact on the Bahamas and Caribbean (see below). Many scientists, particularly those who believe that global cataclysms very rarely rock the world, are strictly against the team’s theories.

‘There is a tendency in this field to label any circular feature a crater,’ says Michael Oskin of the University of North Carolina in Chapel Hill, who surely had in mind the famous Carolina Bays when he said these words. These are literally ten of thousands of elliptical craters, orientated northwest to southeast that cover large areas of not just the Carolinas but several states from New York down to Florida. Many are in swampland and filled with water, thus are taken simply to be wind-created lakes or ponds. Ever since their discovery in the 1930s, following the advent of aerial photography, there has been mounting speculation that the Carolina Bays, and other similar elliptical craters in the Yukon permafrost, are impact craters caused by either the aerial bombardment of meteorites, or the fragments of some more substantial object such a comet or asteroid, similar to that suspected of causing the Tunguska explosion in a remote forested region of Siberia in 1908.

Carbon-dating evidence from the Carolina Bays has provided compelling evidence that they were formed around the end of the Pleistocene period, and many bear characteristic lips or banks at their southeast ends, suggesting that whatever caused them arrived from the northwest, the same direction as the bright object which passed overhead immediately before the Tunguska explosion.

Speaking of Oskin’s skepticism, Asish Basu, a geochemist at the University of Rochester, New York, believes that the findings presented by the team are sound, and their evidence for an extraterrestrial explosion is convincing. ‘I think it is a very straight forward case of an impact.’


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« Reply #28 on: September 16, 2009, 11:50:03 pm »

It Came From the North

Since no large impact site has yet been found, Arizona-based geophysicist and team member Allen West, likewise offers the solution that the object was ‘a low density object’, i.e. a comet that fragmented into many pieces as it entered the atmosphere, causing a series of ‘massive aerial explosions’, each one similar to what happened in Tunguska back in 1908, which spread gradually southwards.

So far no epicentre for the proposed cataclysm has been determined, though the geologists are currently searching in the north of the North American continent, where some of the highest levels of extraterrestrial material have been found. This includes an archaeological site at Gainey in Michigan, which in 12,900 BP lay just beyond the southernmost reach of North American’s primary ice sheet as it receded around the end of the last Ice Age.

Levels of extraterrestrial debris seem to decease further south, suggesting that the comet might well have blown up over Ontario or the Hudson Bay area. Geologists believe that the Great Lakes could well provide vital clues of the catastrophe. Team member Richard Firestone has detected ‘four large holes in the lakes which deeper than Death Valley, so we kind of suspect that pieces of this impact did penetrate them.’ A 400-kilometre long anomaly in the Hudson Bay is also being investigated as a possible rim of a giant impact crater. Yet if the comet did approach from the north or northwest, then it is likely that the largest and heaviest fragments reached further that suspected impact craters such as the Carolina Bays, meaning that marine geologists should be searching beyond their extent in the West Atlantic Basin (a subject also dealt with below).

Another possibility is that the main impact crater was created in the hundreds of metres thick ice sheet north of Michigan, which would have disintegrated, leaving relatively few traces, when finally the ice melted, bringing an end to the last Ice Age.


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« Reply #29 on: September 16, 2009, 11:50:25 pm »

Younger Dryas

Another angle of this powerful discovery is that the 12,900 BP time-frame offered by the evidence of the overall cataclysm fits very well with the sudden re-advance of the ice sheet following some 2,000 years when it had been in withdrawal. This is known to geologists and climatologists as the Younger Dryas.

In the past, the Younger Dryas was put down to climate changes caused by melt waters from the ice sheets flowing into the Great Lakes, and then south through the Mississippi river into the Gulf of Mexico. This then allowed melt water to flow eastward into the Atlantic Ocean, helping to ‘switch off’ the ocean’s saltwater-driven ‘conveyor belt’ current, bringing the entire Gulf Steam to a halt and triggering a mini ice age.

Now, however, there is growing speculation that the Younger Dryas might well have resulted from airborne debris caused by the impact and subsequent firestorms blocking out sunlight, as well as the release of melt water from the primary Ice Sheet that would indeed have flowed eastwards, opening up new drainage channels into the Atlantic Ocean.

‘What we suggest is that the meltwater outflow from the proglacial lakes and from the temporarily melting ice sheet was the result of extraterrestrial impact,’ Jim Kennett explains.

At the same time no less that 35 genera of the continent’s species suddenly became extinct including camels, mastodons, ground sloths and horses, while the Clovis culture, which had flourished for at least a thousand years, diminished by an estimated 70 percent. Previously, the extinction of the Pleistocene animal species has been put down to either the Younger Dryas or over hunting on the part of the hunter-gathering Clovis culture.

However, from 12,900-year-old carbon-rich layers at Murray Springs, Arizona, as well as in sediment cores extracted from examples of the Carolina Bays, chemist Wendy Wolbach has detected ‘significant quantities of soot’, which is unquestionably a product of intense wildfires. Polycyclic aromatic hydrocarbons ­ another signature of wildfires, has also been detected at the team’s sites by geologist Luanne Becker of the University of California, Santa Barbara.

The conclusion is obvious say the team. Huge wildfires swept across the North American continent following the impacts, destroying whole populations of animals and humans. ‘I don’t want to sound catastrophic here,’ said Kennett, ‘but this is wild stuff. There is significant evidence of massive biomass burning.’

Archaeologist Al Goodyear of the University of South Carolina, told the conference that there is ‘indirect evidence of a human disaster in what is now the south-eastern US’. Distinctive style Clovis points suddenly disappear, only to be replaced around 12,700 BP by another style altogether known collectively as ‘red points’. These then outnumber the Clovis point 4 to 1, which if an indication of the rapid depletion of the population, strongly suggesting that up to 70 percent of the Clovis population no longer existed.

As previously mentioned, it is going to be a hard struggle convincing cataclysm skeptics of this incredible new scenario at the end of the Pleistocene epoch. As Kennett jokes: ‘You watch it, there will be blood on the streets.’

For further information, see the New Scientist online story ‘Did a comet wipe out prehistoric Americans’ found at environment.newscientist.com/article/ dn11909-did-a-comet-wipe-out-prehistoric-americans.html


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