Posted on 06/02/2007 3:14:23 PM PDT by blam
Ice Age Ends Smashingly: Did a comet blow up over eastern Canada?
Sid Perkins
Evidence unearthed at more than two dozen sites across North America suggests that an extraterrestrial object exploded in Earth's atmosphere above Canada about 12,900 years ago, just as the climate was warming at the end of the last ice age. The explosion sparked immense wildfires, devastated North America's ecosystems and prehistoric cultures, and triggered a millennium-long cold spell, scientists say.
IT'S IN THERE. A layer of carbon-rich sediment (arrow) found here at Murray Springs, Ariz., and elsewhere across North America, provides evidence that an extraterrestrial object blew up over Canada 12,900 years ago. The hallmarks include lumps of glasslike carbon (top), carbon spherules (middle, in cross section), and magnetic grains rich in iridium (bottom). West; (middle inset): Cannon Microprobe
At sites stretching from California to the Carolinas and as far north as Alberta and Saskatchewan—many of which were home to prehistoric people of the Clovis culture—researchers have long noted an enigmatic layer of carbon-rich sediment that was laid down nearly 13 millennia ago. "Clovis artifacts are never found above this black mat," says Allen West, a geophysicist with Geoscience Consulting in Dewey, Ariz. The layer, typically a few millimeters thick, lies between older, underlying strata that are chock-full of mammoth bones and younger, fossilfree sediments immediately above, he notes.
New analyses of samples taken from 26 of those sites reveal several hallmarks of an extraterrestrial object's impact, West and his colleagues reported at the spring meeting of the American Geophysical Union in Acapulco, Mexico.
Samples from the base of the black mat yield most of the clues to its extraterrestrial origin, says Richard B. Firestone, West's coworker and a nuclear physicist at the Lawrence Berkeley (Calif.)
(Excerpt) Read more at sciencenews.org ...
Ten thousand years of ADDITIONAL weather can do a lot of stuff ~ the circles are known in other places.
Google Permafrost polygonal forms. Lots of research and literature on this topic, including many locations where these forms are artifacts of earlier climatic conditions. Has anyone published a paper suggesting the the Carolina Bays are permafrost artifacts?
Your typical circle or oval as found in nature is obviously a “polygon”.
My backyard and beyond for five miles is pretty much these permafrost hexagons. They are fairly uniform in size, but I would have to guess how big they are. Maybe fifty feet across.
Now, look down the road a couple of centuries to a time when there is no permafrost in the area and hurricanes regularly sweep up the Gulf of Alaska to laywaste Alaskan coastal areas ~ think of what those polygons are going to look like.
When the permafrost melts the land sinks and fills with water. Then the water fills with vegetation and eventually it becomes dry land again. The formation remains so you can see how it came about. Lots of low grade peat around here. We have examples of all stages of permafrost activity including pingos. Fascinating to watch and it changes fast enough to actually see it happen.
And me as well, Renfield, for the caustic lecture you gave me about the demise of North American megafauna. I expressed the (to you) heretical notion that they might have suddenly perished by some means other than over-hunting by Clovis tribes.
While this new theory doesn't give any final answers, it lends credence to my long-held hunch that catastrophism or disease played a much greater role than over-hunting.
Benjamin Franklin was in haplogroup ‘V’ (Sa’ami).
No point in trying to educate muawiyah, he believes what he wants to believe and is not going to be swayed by mere logic, evidence, facts, or anything else for that matter.
I personally think that the Carolina Bays were formed by the Little People, since it is a well known fact that the Irish were here long before Columbus and the Vikings.
“...You probably owe me an apology over the ‘scolding’ you gave me about the Carolina Bays (absolutely) not having a celestial origin.....”
No, I don’t. Carolina Bays are NOT of celestial orgin; they are, as we discussed before, deflation basins. Many of the bays predate the 12,900 year age mentioned in the article, and some geologic formations have no bays, while other adjacent formations do.
“...Why are the circles elliptical and oriented in a direction? At Prudhoe Bay there are similar looking features shaped by prevailing wind....”
Carolina bays were shaped by the prevailing wind, too, which in this case, is from the southwest. When water tables were seasonally high, the wind blowing from the sw caused waves in the (ponded) bays, having maximum scouring effect along the edges of the bays that were perpendicular to the wind (i.e., NW and SE edges). The scouring caused disaggregation of fines. Then when the water tables dropped seasonally, the fines were picked up by the wind and redeposited offsite.
Comets don’t choose to do that, they aren’t animate (IMHO). Heating due to passage through the atmosphere during terminal descent causes smaller objects to bust apart and, yes, explode above the impact site. That’s what happened in 1908 above Tunguska. Very large objects don’t generally fall apart during descent, unless they’re already fragments which had wound up stuck together during their long sojourn around the Sun.
:’) One event, one distribution area.
The discussion drifted to the Carolina coast ~ no permafrost. They haven't had anything catastrophic other than recurring nasty earthquakes (worst ever East of New Madrid) and hurricanes.
We have only the vaguest notion of what shape polygons were produced by the freeze/thaw cycle in that neck of the woods 10,000 years ago. My guess is they were more circular than irregular.
My own front yard consists of trillions of ice shaped rocks. I have no idea what the freeze/thaw cycle did with them back in the Ice Age ~ but Fur Shur it put them on the surface, and about that peat, ain't any here!
Maybe. But, that doesn’t necessarily result in elliptical holes. Weather erosion of the pits could do that if they are water-filled.
During the Younger Dryas, however, we had a resumption of a near polar freeze/thaw cycle for just under a thousand years. There are all sorts of strange ice shaped ground features in this region ~
Probably so. If we look at other examples of impact craters, such as Mercury, the moon, Mars, any of the various rocky moons imaged by various spacecraft, we see round craters. Not many elongated craters. In fact, I don’t recall any examples. Did every meteoroid impact come straight down from vertical?
No, most of them have an incident angle; but they still tend to leave round craters.
See Post #50, I think we are digging in the wrong backyard.
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