Posted on 12/22/2006 11:19:39 AM PST by blam
Mysterious Egyptian Glass Formed by Meteorite Strike, Study Says
Stefan Lovgren
for National Geographic News
December 21, 2006
Strange specimens of natural glass found in the Egyptian desert are products of a meteorite slamming into Earth between 100,000 and 200,000 years ago, scientists have concluded.
The glassknown locally as Dakhla glassrepresents the first clear evidence of a meteorite striking an area populated by humans.
At the time of the impact, the Dakhla Oasis, located in the western part of modern-day Egypt, resembled the African savanna and was inhabited by early humans, according to archaeological evidence (see Egypt map.)
"This meteorite event would have been catastrophic for all living things," said Maxine Kleindienst, an anthropologist at the University of Toronto in Canada.
"Even a relatively small impact would have exterminated all life for [several] miles."
Crater Mystery
The origin of the glass had puzzled scientists since Kleindienst discovered it in 1987.
Some researchers had suggested the Stone Age glass may have been produced by burning vegetation or lightning strikes.
But a chemical analysis showed that the glass was created in temperatures so high that they could only have been the result of a meteorite impact.
Gordon Osinski, a geologist at the Canadian Space Agency in Saint-Hubert who conducted the analysis, found that the glass samples contain strands of molten quartz, a signature of meteorite impacts.
"We can now say for definite that they were caused by a meteorite impact," he said.
Osinski is the lead author of the paper detailing the findings, which was published online in ScienceDirect. The glass deposits have been found in desert locations separated by tens of kilometers, suggesting a massive event.
But scientists have found no signs of an impact crater in the area.
Enlarge Photo
"Usually from an impact like this, we should have a crater at least a kilometer [0.6 mile] across," Osinski said.
The absence of a crater, the scientists believe, suggests that the large space rock may have disintegrated upon entering Earth's atmosphere.
What happened may have been similar to the so-called Tunguska event, in which an asteroid exploded miles above the Earth's surface in a remote area of Siberia in 1908. That explosion felled an estimated 60 million trees over 830 square miles (2,150 square kilometers).
"There was no hole in the ground at Tunguska either," said Albert Haldemann, a planetary scientist at the Jet Propulsion Laboratory in Pasadena, California, who has been using radar to scour the Egyptian desert for impact signs.
"In an air burst like that, contents of the explosion continue to travel downward providing a gas pulse across the [Earth's] surface that could vitrify sediments," Haldemann explained.
Life-Forms Killed
Scientists know much more about what happens when meteorites hit hard rock than when they impact sand and sedimentary rock, as would have been the case in the Egyptian desert.
At the time, there was a large lake in the area, the researchers say.
"If there was an impact at the surface and it happened to hit the lake, it wouldn't be surprising if the [crater] was filled in," Haldemann said.
"Did the event boil the entire lake away, or did it just cause a really big wave to go across the lake? Maybe we can figure that out from the sediments."
Kleindienst, the anthropologist, has been excavating the site for more than 20 years as part of the Dakhla Oasis project.
(Her research has been partially funded by the National Geographic Committee for Research and Exploration. The committee and National Geographic News are both divisions of the National Geographic Society.)
Kleindienst has obtained a large amount of evidence, including spears and scrapers, to show that humans continually inhabited this region of Egypt's Western Desert during the Middle Stone Age, from about 200,000 to 30,000 years ago.
She has even found glass in lake sediments with archaeological evidence of human habitation in the soil layers below and above it.
"There is no reason to suspect that humans were not there at the time that this catastrophe happened," she said.
The meteorite research has important implications for understanding the environmental and human history at the time, Kleindienst added.
"Calculations at Meteor Crater [in Arizona] give some idea of what the effect of a [relatively small] impact would be," she said.
"Life-forms are killed or seriously injured for many tens of kilometers away from the impact."
"If this event happened during a humid period, the area might have been ecologically repopulated fairly quickly from surrounding areas," she added.
"But if it happened during a dry period, it might have taken a considerable period for life to be re-established in the oasis region."
Haldemann, who is also the deputy project scientist on NASA's Mars Exploration Rover project, says the meteorite strike underlines the interconnectedness between Earth and the rest of the solar system.
"We already know the environment of the whole Earth is tied together," he said.
"What we've been learning more and more in the last 20 years or so is that we're also tied to the solar system as a whole over longer time periods and that this interaction tends to be punctuated by these catastrophic events."
"Here we have evidence in the [Early Stone Age] records that this kind of thing can really happen to us."
King Tut has some jewelery made from impact glass. This could be the site.(?)
100,000 to 200,000 years in the future, archeologists will attribute glass found in the deserts of the middle east to an exchange of nuclear weapons. /12monkeys
Wrong!
What's that guy sticking his head into? Is that how Arabs wash their faces? Haven't we seen that photo before?
I can't believe they used the term "life-forms." That is so Star Trek.
Professor Mike Baillie speculates that the whole Beowulf thing was about an impact event.
That almost looks naughty.
Or it's a depiction of the MSM approaching Hillary from behind for an interview.
Is this stuff the same as Nakhlite, or a meteorite with a different origin?
The amusing thing about this site...is that a couple of folks have tried to tie alien visitation deal with glass production. And there is one group that suggested a ancient laser had been used to make these (The Atlantis Blueprint). There are alot of "hits" on the the earth...and sooner or later...we will have another. Statistically....you can't avoid another hit.
Yup. I read somewhere that statistically we are over-due for an impact. Just like we're over due for a pandemic and a super-volcano. So...
Let me guess...John Effin Kerry, NASA, 2004
I apologize. I didn't mean to hit and run. Was just busy. For more info on the black stone, click below.
http://en.wikipedia.org/wiki/Black_Stone
"The Black Stone's origin
Just as there are various viewpoints regarding the religious significance of the Stone, there are also various opinions as to its history and nature."
snip
"Secular historians point to the history of meteorite worship, in pre-Islamic Arabia, and say it is likely that the Stone is a meteorite or possibly impact glass, from the meteorite impact crater at Wabar, about 1100 km from Mecca.[5]. There is no way to test this hypothesis without removing and examining the Stone, which would not be permitted by its guardians."
Some believe the Angel Gabriel was a meteorite.
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