From the University of California – Santa Barbara
Study finds new evidence supporting theory of extraterrestrial impact
(Santa Barbara, Calif.) –– An 18-member international team of researchers that includes James Kennett, professor of earth science at UC Santa Barbara, has discovered melt-glass material in a thin layer of sedimentary rock in Pennsylvania, South Carolina, and Syria. According to the researchers, the material –– which dates back nearly 13,000 years –– was formed at temperatures of 1,700 to 2,200 degrees Celsius (3,100 to 3,600 degrees Fahrenheit), and is the result of a cosmic body impacting Earth.
These new data are the latest to strongly support the controversial Younger Dryas Boundary (YDB) hypothesis, which proposes that a cosmic impact occurred 12,900 years ago at the onset of an unusual cold climatic period called the Younger Dryas. This episode occurred at or close to the time of major extinction of the North American megafauna, including mammoths and giant ground sloths; and the disappearance of the prehistoric and widely distributed Clovis culture. The researchers’ findings appear today in the Proceedings of the National Academy of Sciences.
“These scientists have identified three contemporaneous levels more than 12,000 years ago, on two continents yielding siliceous scoria-like objects (SLO’s),” said H. Richard Lane, program director of National Science Foundation’s Division of Earth Sciences, which funded the research. “SLO’s are indicative of high-energy cosmic airbursts/impacts, bolstering the contention that these events induced the beginning of the Younger Dryas. That time was a major departure in biotic, human and climate history.”
Microscopic Images of Grains of Melted Quartz
Morphological and geochemical evidence of the melt-glass confirms that the material is not cosmic, volcanic, or of human-made origin. “The very high temperature melt-glass appears identical to that produced in known cosmic impact events such as Meteor Crater in Arizona, and the Australasian tektite field,” said Kennett.
“The melt material also matches melt-glass produced by the Trinity nuclear airburst of 1945 in Socorro, New Mexico,” he continued. “The extreme temperatures required are equal to those of an atomic bomb blast, high enough to make sand melt and boil.”
The material evidence supporting the YDB cosmic impact hypothesis spans three continents, and covers nearly one-third of the planet, from California to Western Europe, and into the Middle East. The discovery extends the range of evidence into Germany and Syria, the easternmost site yet identified in the northern hemisphere. The researchers have yet to identify a limit to the debris field of the impact.
Photos of Melt Glass Known as Trinitite
“Because these three sites in North America and the Middle East are separated by 1,000 to 10,000 kilometers, there were most likely three or more major impact/airburst epicenters for the YDB impact event, likely caused by a swarm of cosmic objects that were fragments of either a meteorite or comet,” said Kennett.
The PNAS paper also presents examples of recent independent research that supports the YDB cosmic impact hypothesis, and supports two independent groups that found melt-glass in the YDB layers in Arizona and Venezuela. “The results strongly refute the assertion of some critics that ‘no one can replicate’ the YDB evidence, or that the materials simply fell from space non-catastrophically,” Kennett noted.
He added that the archaeological site in Syria where the melt-glass material was found –– Abu Hureyra, in the Euphrates Valley –– is one of the few sites of its kind that record the transition from nomadic hunter-gatherers to farmer-hunters who live in permanent villages. “Archeologists and anthropologists consider this area the ‘birthplace of agriculture,’ which occurred close to 12,900 years ago,” Kennett said.
“The presence of a thick charcoal layer in the ancient village in Syria indicates a major fire associated with the melt-glass and impact spherules 12,900 years ago,” he continued. “Evidence suggests that the effects on that settlement and its inhabitants would have been severe.”
Other scientists contributing to the research include Ted Bunch and James H. Wittke of Northern Arizona University; Robert E. Hermes of Los Alamos National Laboratory; Andrew Moore of the Rochester Institute of Technology; James C. Weaver of Harvard University; Douglas J. Kennett of Pennsylvania State University; Paul S. DeCarli of SRI International; James L. Bischoff of the U.S. Geological Survey; Gordon C. Hillman of the University College London; George A. Howard of Restoration Systems; David R. Kimbel of Kimstar Research; Gunther Kletetschka of Charles University in Prague, and of the Czech Academy of Science; Carl Lipo and Sachiko Sakai of California State University, Long Beach; Zsolt Revay of the Technical University of Munich in Germany; Allen West of GeoScience Consulting; and Richard B. Firestone of Lawrence Berkeley National Laboratory.
As for the comically naive suggestion that a catastrophe led to the invention of agriculture, let’s ponder the question of how agriculture did get started. Certainly not by hunters only; by hunter-gatherers, possibly. By grain gatherers, almost certainly. Here’s how.
Grain gatherers bring their baskets of grain to the hut or tent. The baby tips the basket over and they do their best to clean it up. After the next rain sprouts grow and they harvest grain right by the tent or hut. Most likely a tent, because there was no reason for a stationary hut before they knew how to grow their own grain. So they visit a previous camp site and lo, there is grain growing right where the baby spilled the basket. And after this happens a few thousand times some wise guy says, why should only the baby spill the grain? So eventually they start building permanent huts.
Now if you can tell us how sudden or gradual climate change helped the baby spill the basket, be our guest. People did not start eating grain because of a meteor shower. Maybe a meteor knocked the basket over. –AGF
>Dr. Lurtz says:
>June 13, 2012 at 6:57 am
>Could it be that the “cosmic” items some how “parted the atmosphere” and opened the surface >of the Earth directly to the vacuum of space. This is the only way the temperature could fall >~200F instantaneously [Sun pointing away or cooking (bbq mammoth) would have occurred]. A >volcano or Earth shift could not do this!
I have been thinking this must be what happened. I am glad to see someone else say it.
Faux Science Slayer says:
June 13, 2012 at 9:03 am
[eternally grateful to attend Anthony’s world wide science class]….
___________________________________________
Amen!
WUWT should be required reading for 9 -12 graders. With luck home Schoolers do just that.
I certainly looks like it was a swarm of meteors. I would not be surprised if the Earth got hit more than once by the swarm until she cleaned the area. The Younger Dryas stadial, was a 1300 ± 70 years. So repeated hits over time make a kind of sense.
My first morning post disappeared entirely. I’ll try again.
Julian Braggins says:
June 13, 2012 at 11:28 pm
“As for Wrangel Island, that is another argument and not in itself enough to refute the main evidence, dating being notoriously unreliable particularly when high radiation is involved.”
======================================================================
And what if no radiation is involved? This handwaving allows you to take every frozen mammoth no matter what its C14 date and claim it died together with every other frozen mammoth found. It’s bad enough saying humans didn’t wipe out the big game, when the archeological evidence is overwhelming that everywhere humans first appeared the big game disappeared. Climate change is the rule, and the critters usually cope. CNGC (catastrophic natural global cooling) is no more scientific than CAGW, so your blaming dead mammoths on a meteor is doubly unscientific, triple so when you reject C14 dating of mammoth carcasses.
Your links are no better. For some round earth science see:
http://www.talkorigins.org/faqs/mammoths.html
which give some C14 dates for specimens. Creationists have a heyday with this stuff, and lots of the scientists show themselves to be creationists at heart. –AGF
The whole Mammoth meme getting pretty tired, and old. In point of fact, if folks would take the time to actually read the papers produced by researchers working on the stratigraphy of the Younger Dryas Boundary layer, instead of getting caught up in the tripe propduced by crappy science reporting, they’d know that not even one paper has ever said that Mammoth existed below the Younger Dryas Boundary Layer, but not above it.
You mean like this short notice discovery??
Only 3 days notice of its existence, larger bodies might be noticed earlier, but even so just a few days or weeks prior notice is hardly sufficient to do anything at all to mitigate an impact let alone prevent one.
Read more: http://www.foxnews.com/scitech/2012/06/14/huge-asteroid-to-fly-by-earth-thursday-how-to-watch-online/#ixzz1xnbqk5jc
@pkatt June 14, 2012 at 12:09 am:
“Whose to say all of the ice ages were not caused by such events?”
That is pretty much my take on Heinrich Events and Dansgaard-Oeschger Events, that they come about because we pass through the denser part of the Taurids and get whacked. If the Taurids are essentially regular it only seems logical that our damaging periods would happen with some regularity. In fact, if one starts from that assumption and works backward, one might be able to make some falsifiable predictions about the makeup of the Taurid stream.
All this doesn’t make it true, but surely something that should be looked into.
Steve Garcia
@Mark June 13, 2012 at 1:52 pm:
Nyeshet – Exactly correct. The original YD impact group has been maligned because they didn’t have the entire multi-disciplinary picture right on the first go-around. But this is an event that needs ongoing disvcoveries – and ones that can be looked at from that perspective. If that first Firestone group had not put the ida out there a lot of this evidence would be being identified/interpreted as something else altogether. At some point someone had to step up and say, “Look, if we put 2+2 together here, we see the answer being 4.” Evidence like this paper is going to keep on coming up, now that people have a framework within which to place the evidence. The evidence does not have to be enigmatic or anomalous anymore.
This is still very early in the game. Now that people are beginning to be open-minded about this possibility they are able to put multiple minds together in several fields, so people are now LOOKING to see if these impact sites exist, using the best thinking they can put into it. Expect more and more of this kind of find. The science will prove out in the end, one way or the other. As time has moved along, truly independent researchers are finding such evidence. Some are still sitting on the fence on interpreting their finds, but their evidence is still consistent with this hypothesis.
Steve Garcia
@R.S.Brown June 13, 2012 at 2:55 pm
All your points are exactly correct. Although Mark Boslough is doing hypervelocity modeling (at Sandia National Labs, I think), we don’t know how many variations he has performed.
The desnsity/friability of the object is of prime importance, as well as how long it is in the atmosphere. A vertical descent is in the atmosphere the shortest amount of time. Yet almost every meteor I’ve seen on video is shown on some low trajectory, which means a relatively long time in the atmosphere – and subsequently more chance of exploding above ground. And the low point of any tangential or near-tangential trajectory varies, with air density varying along with that, meaning wildly varying heat build-up. All these variables make for a very complex scenario, and if comet advocates haven’t figured it all out yet, no duh! It takes time to develop the right questions to ask so that the right experiments can be run and the right ground evidence be collected and put into perspective.
There is a bit of discussion at CosmicTusk.com on this, very much along the lines you are discussing. But CosmicTusk people have very little (if any) effect on what runs to do. We DO need some idea of what is happening when these kinds of events occur. There are all kinds of solid ideas out there, but no way of sorting through them yet.
We are all very early in the continuum of this inquiry. As in any overturning hypothesis, at the beginning the naysayers have had the bulk of evidence on their side. But that is because the pros collection of evidence has had few artifacts yet. We keep on seeing the adding of new evidence, and the great bulk of what is being found is supportive of the premise. The weight of the evidence is turning…
Steve Garcia
@Dennis Cox June 13, 2012 at 3:09 pm:
Touché, Dennis.
You saved me the trouble of saying the same thing: Those Daulton, etc., claims are well rebutted and show that Daulton’s own team failed to do due diligence. Unfortunately, his unsupportable snack got 50 times the press of the rebuttals.
To whit: Thank you, Anthony, for posting this! This post is probably expanding the exposure of this important study beyond all other news sources put together.
Steve Garcia
@Don J. Easterbrook June 13, 2012 at 8:21 pm:
Don, your questions are all valid and do need to be addressed. I would say give it time. It is early in the game, and more and more evidence is turning up. Expect to see answers to your questions, one by one, as this all fleshes out.
All that is available now is the Abstract, so why don’t we wait till we can see the paper?
Fair enough. Yes, let’s be skeptical, as long as an open mind comes with the doubt. That is the way of science: Let the chips fall where they may. Momentum is moving in the direction of eventual confirmation. But it may be a long slog.
Steve Garcia
Tim Mantyla @ur momisugly June 13 12:10 pm launches into a supercilious rant of a type common to CAGW true-believers: anyone who disagrees with his preferred conclusions is “anti-science,” regardless of how much scientific evidence is cited in support. Notably, TM fails to explain precisely what he thinks is “unscientific” and offers no countervailing argument.
TM apparently was set off by the observation by Vince Causey that the evidence for a possible extraterrestrial impact origin for the YD implies that “the Younger Dryas was not part of a ‘natural rhythm’, that the natural rhythm induced ice age ended 20,000 years ago and not 12,000 years ago. Implications: we are now due for the next ice age.”
I would quote TM’s scientific basis for objecting to Causey’s observation, but there is nothing to quote. TM’s rant is unconnected with any rational argument. What follows is mere diatribe.
To me, Causey raises a scientifically valid and interesting point. Since TM seems not to have understood, let me set the matter forth in more detail:
1. For the last 1-2 million years the earth has experienced recurrent glaciations on a periodicity of roughly 100,000 years. The evidence is presented and reproduced in so many places that I won’t bother with a citation; it doesn’t seem to be controversial even among CAGWists.
2. The recurrent glaciation events are not Swiss timepieces, but they are surprisingly uniform in period for geological occurrences, consistent with proposed astronomical explanations. The most parsimonious expectation is that the periodicity of glaciation will continue into the future. Thus if we can properly establish the onset of a glaciation event (such as the beginning of a warm period) then we may extrapolate to the onset of future events in the cycle.
3. Interglacial warm periods tend to last about 15,000 years. The onset of warm periods is abrupt, whereas the decline is gradual; thus the duration of a warm period depends on how you define the amount of decline needed to mark its end. But by 15,000 years after onset of a warm period, the cooling trend is evident (on a millennial time scale) for all preceding glaciation events of the last 1,000,000+ years. Notably, the peak warming of the present interglacial (the “Holocene optimum”)
occurred 6,000-8,000 years ago, and the recent warming remains well below the temperatures of 6,000 years ago. The earth appears to remain in a secular cooling trend.
4. If the Holocene onset should be dated to the end of the Younger Dryas 11,900 years ago, then we might reasonably expect a few more millennia of warmth. If however the Holocene onset should be dated to the warming period before the Younger Dryas cooling, then the current interglacial period is several thousand years older. Based on prior glaciations, we should anticipate a new glaciation might begin much sooner.
So, TM, exactly what is “unscientific” in the preceding argument? Do you disagree with any of the above factual assertions? If so, please explain; as I mentioned already, I don’t think the timing and duration of previous glaciations are very controversial for either warmists or skeptics. Do you think the logical inferences are unsupported? If so please explain precisely how.
TM, you have castigated the science here without offering specifics. It’s time for you to engage with the actual argument rather than retreat into generalities: put up or shut up.
Some of you newcomers to skeptical climate science should take a look at this graph:
http://en.wikipedia.org/wiki/File:Vostok_420ky_4curves_insolation.jpg
Insolation at 65 degrees north latitude in June varies by 100W/m^2 TOA and by similar amounts wherever the edge of the northern ice happens to be. Oxygen isotopes and reconstructed temperature follow Milankovitch Cycles closely, with a lag long enough to account for melting and freezing ice caps. That’s 100W/m (TOA) versus 1.6W for CO2 IR. CO2, volcanos, and meteors are hardly blips on the screen. –AGF
agfosterjr says:
June 14, 2012 at 10:53 am
Steve P says, or tried to:
June 14, 2012 at 3:42 pm
But the big game animals have not disappeared in Africa and parts of Asia, where mega-fauna remain despite the presence of humans beating the bush for the cook-pot for a very long time on those continents.
Interesting to see the language used on the frontiers.
Evidence here, as with various other special-interest issues that Anthony tends to fight shy of, of an emotional poiarization of views between those who dismiss “naive believers” but are then shown to be naive believers themselves who are in denial of various bits of hard evidence that will not go away – and those who sound suspiciously naive / transcendental-ranting at first, and have dubious and even objectionable website links, but then show interesting hard evidence.
To me, this shows one can be well-versed, intelligent and open in one area and completely naive and intolerant in another area. To me, the challenge is how to find blog language and behaviour that allows courteous exploration of subjects where at least some of the associated material is, or seems to be, objectionable. Right now I’m working closely with someone who is a brilliant and innovative scientist and engineer in one direction, but is (at present!) firmly convinced in AGW.
It is important to be able to investigate things without people making the mere investigation impossible. This requires that investigators take extra trouble to show their approach is in keeping with the spirit of science, if not its familiar letter; and that those who criticize don’t forget that the best scientists show mystical, intuitive sides that at first sight don’t look scientific (Newton for example) – and that many have been ruthlessly punished for such things, in all ages, in ways that are all too familiar – and that ultimately the Universe is a mystery and a wonder of great intrinsic beauty (a word that cannot exist in a purely materialist view of reality).
Thanks Lucy Skywalker,
Something I’ve noticed in this thread is what amounts to a lot of off topic straw man arguments; the mammoth extinction meme, and the myth that they were all flash frozen at the same time being just one of them.
The simple fact is that the authors of the Younger Dryas Impact Hypothesis have never stated that the event caused the extinction of the Mammoths. What they have shown is the global emplacement of an assemblage of markers in the YD boundary layer that can only be explained by a major impact event of catastrophic proportions, and that there is only one other global layer in the stratigraphic record with the same assemblage of impact markers as the YDB; the KT boundary layer that marks the extinction of the dinosaurs 65 million years ago. The specific claim of the authors of the YD impact hypothesis is that only a major impact event that’s different from anything that’s ever been studied before could have produced those markers globally. Multiple large cluster airburst events are proposed.
And the discovery of more impact markers that date to 12,900 YA is the only claim that is being made in the new paper that’s the topic of this thread.
Nor have the Authors of the YDIH ever categorically stated that the event was the trigger for the start of the Younger Dryas cooling. They have simply pointed out that the timing of the emplacement of a global impact layer with only one other comparable example in the stratigraphic record, that being the KT boundary, coincides with the start of the Younger Dryas Cooling and the Megafaunal extinctions 12,900 YA.
Steve P says:
June 14, 2012 at 3:42 pm
But humans never appeared suddenly in Africa–as early man developed into a dangerous hunter the animals had time to gain a healthy respect for them.. Eurasian mammoths are a somewhat more difficult question, but they specialized in sub-Arctic forage, where humans were also late arrivers. In the Old World the devlopment of mesolithic technology was more sudden than human arrival. –AGF
Albeit off topic (and mentioned above), as far as exiting the current interglacial period (as much as I’d like it to start soon to prevent current political and monetary strategies), since the orbital parameters are very similar to that which occurred 420kyrs ago (eccentricity and obliquity in phase), our current interglacial could last another 2kyrs. Here is a graph of overlayed starts of interglacials (Vostok). The similar 420kyr interglacial was ~2kyrs longer than the current interglacial.
http://s852.photobucket.com/albums/ab89/etregembo/?action=view¤t=GW_08202007_9174_image001-1.gif
NOVA | End of the Big Beasts
http://www.pbs.org/wgbh/nova/evolution/end-big-beasts.html
In all likelihood, not one thing, but a combination of problems for the mega-mammals probably led to their demise.
And to Gail, Earth may have just been in the crossfire between Jupiter and the Sun when this comet was torn apart by their gravitational pulling or whatever. Jupiter and the sun probably did most of the cleaning out. The stream of material coming off the comet could not have just stopped in outer space with nothing to slow it. I just hope all of the big material was captured by gravity and gobbled up by the two giants in our solar system.
agfosterjr says:
June 14, 2012 at 9:28 am
As for the comically naive suggestion that a catastrophe led to the invention of agriculture, let’s ponder the question of how agriculture did get started. Certainly not by hunters only; by hunter-gatherers, possibly. By grain gatherers, almost certainly. Here’s how. ~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By transposing the particular to the general you created the comedy. You asked how a catastrophe COULD lead to agriculture, I gave as logical an answer as your proposition which may well be true, but not exclusive.
For photos and some idea of the extent of the catastrophic die off, Alaska, Canada, through northern Europe and Siberia ~ 10,000- 12000 yrs ago see :-
http://www.s8int.com/boneyard4.html
and read all the pages for other catastrophic evidence in fossil beds
****
Julian Braggins says:
June 15, 2012 at 3:02 am
For photos and some idea of the extent of the catastrophic die off, Alaska, Canada, through northern Europe and Siberia ~ 10,000- 12000 yrs ago see :-
http://www.s8int.com/boneyard4.html
and read all the pages for other catastrophic evidence in fossil beds
****
Thanks for the link, Julian. Astonishing. That should convince anyone that the evidence of a non-human-caused catastrophe killing massive numbers of mega-fauna is overwhelming.
agfosterjr says:
June 14, 2012 at 9:28 am
As for the comically naive suggestion that a catastrophe led to the invention of agriculture, let’s ponder the question of how agriculture did get started. Certainly not by hunters only; by hunter-gatherers, possibly. By grain gatherers, almost certainly. Here’s how.
Now if you can tell us how sudden or gradual climate change helped the baby spill the basket, be our guest. People did not start eating grain because of a meteor shower. Maybe a meteor knocked the basket over. –AGF
**********************************************************************************************
The question of the start of agriculture (Off topic I know, sorry) was mentioned in Ryan & Pitman’s “Noah’s Flood”, about the re-flooding of the Black Sea and Stephen Oppenheimer’s “Eden in the East”, in which he posits the rise in sea levels over the South China Sea causing human migration bringing agriculture from there to Mesopotamia. Ryan & Pitman in particular offer the “Oasis hypothesis” according to which the Ice Age aridity of central Asia trapped bands of humans and prey animals close to water and so humans had to take up husbandry to avoid starvation. Not sure if either cause is rapid enough to count as a catastrophe, though.
beng says:
June 15, 2012 at 5:37 am
****
Julian Braggins says:
June 15, 2012 at 3:02 am
=================================================================
That link is some of the silliest nonsense we’ll ever hope to read. You could not support a word of it with good evidence. –AGF
Buried (silted over) at the bottom of Hudson Bay, for the biggest chunk, with accompanying smaller meteors airbursting elsewhere?
Naively speaking, James Bay has always looked like an entrance (exit?) ‘ramp’. And Hudson Bay is so damn circular …
🙂