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Study: Dinosaurs Died Within Hours After Asteroid Hit
University of Colorado News Center ^ | May 24, 2004

Posted on 07/08/2004 12:29:19 AM PDT by LibWhacker

According to new research led by a University of Colorado at Boulder geophysicist, a giant asteroid that hit the coast of Mexico 65 million years ago probably incinerated all the large dinosaurs that were alive at the time in only a few hours, and only those organisms already sheltered in burrows or in water were left alive.

The six-mile-in-diameter asteroid is thought to have hit Chicxulub in the Yucatan, striking with the energy of 100 million megatons of TNT, said chief author and Researcher Doug Robertson of the department of geological sciences and the Cooperative Institute for Research in Environmental Sciences. The "heat pulse" caused by re-entering ejected matter would have reached around the globe, igniting fires and burning up all terrestrial organisms not sheltered in burrows or in water, he said.

A paper on the subject was published by Robertson in the May-June issue of the Bulletin of the Geological Society of America. Co-authors include CU-Boulder Professor Owen Toon, University of Wyoming Professors Malcolm McKenna and Jason Lillegraven and California Academy of Sciences Researcher Sylvia Hope.

"The kinetic energy of the ejected matter would have dissipated as heat in the upper atmosphere during re-entry, enough heat to make the normally blue sky turn red-hot for hours," said Robertson. Scientists have speculated for more than a decade that the entire surface of the Earth below would have been baked by the equivalent of a global oven set on broil.

The evidence of terrestrial ruin is compelling, said Robertson, noting that tiny spheres of melted rock are found in the Cretaceous-Tertiary, or KT, boundary around the globe. The spheres in the clay are remnants of the rocky masses that were vaporized and ejected into sub-orbital trajectories by the impact.

A nearly worldwide clay layer laced with soot and extra-terrestrial iridium also records the impact and global firestorm that followed the impact.

The spheres, the heat pulse and the soot all have been known for some time, but their implications for survival of organisms on land have not been explained well, said Robertson. Many scientists have been curious about how any animal species such as primitive birds, mammals and amphibians managed to survive the global disaster that killed off all the existing dinosaurs.

Robertson and colleagues have provided a new hypothesis for the differential pattern of survival among land vertebrates at the end of the Cretaceous. They have focused on the question of which groups of vertebrates were likely to have been sheltered underground or underwater at the time of the impact.

Their answer closely matches the observed patterns of survival. Pterosaurs and non-avian dinosaurs had no obvious adaptations for burrowing or swimming and became extinct. In contrast, the vertebrates that could burrow in holes or shelter in water -- mammals, birds, crocodilians, snakes, lizards, turtles and amphibians -- for the most part survived.

Terrestrial vertebrates that survived also were exposed to the secondary effects of a radically altered, inhospitable environment. "Future studies of early Paleocene events on land may be illuminated by this new view of the KT catastrophe," said Robertson.


TOPICS: News/Current Events
KEYWORDS: archaeology; asteroid; catastrophism; chicxulub; crevolist; deccantraps; dinosaurs; economic; ggg; godsgravesglyphs; history; theory
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To: swilhelm73
And wouldn't that have killed every land plant?

Ever see how quickly they springs back after a forest fire?
41 posted on 07/08/2004 2:56:41 AM PDT by R. Scott (Humanity i love you because when you're hard up you pawn your Intelligence to buy a drink.)
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To: lelio

One of the clues is the size of the crater, which is still extant.


42 posted on 07/08/2004 3:03:08 AM PDT by Junior (FABRICATI DIEM, PVNC)
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To: lelio
Where on earth did he get this figure from?

The first Hydrogen (Fusion) bomb was approx 10.4 Megatons.
It left a crater a mile wide..

The biggest H-bomb ever tested by the U.S. was 15 Megatons.
It left a crater 250 ft. deep and 6250 ft wide..

What's the size of the Yucatan Crater?
I would guess about 10 miles wide, and somewhere around 2000 to 2200 ft deep..

i.e., 100 megatons..

The Russians had designs for 100 megaton H-bombs, but never actually tested any.. ( not sure if they ever built one or not )

43 posted on 07/08/2004 3:05:07 AM PDT by Drammach (Ripley... Last survivor of the Nostromo.... signing off....)
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To: Drammach

The Yucatan crater is estimated to be 110 - 125 miles in diameter. I don't know if there is any reliable estimate of depth.


44 posted on 07/08/2004 3:23:37 AM PDT by Truth29
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To: lelio

Here's a link to an interesting article..

http://www.space.com/scienceastronomy/planetearth/asteroid_jello_001122.html

Says the crater is 100 - 150 miles wide..

I would have to revise my estimate another power of 10....

1,000 megatons.. or .. 1 to 1.5 GIGATONS..


45 posted on 07/08/2004 3:24:50 AM PDT by Drammach (Ripley... Last survivor of the Nostromo.... signing off....)
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To: Truth29

Yeah.. I just posted a revised estimate after doing a little googling..


46 posted on 07/08/2004 3:25:49 AM PDT by Drammach (Ripley... Last survivor of the Nostromo.... signing off....)
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To: R. Scott

Over a decade of boiling temperatures and a nearly constant fires are rather a more serious problem for plant life...


47 posted on 07/08/2004 3:36:48 AM PDT by swilhelm73 (We always have been, we are, and I hope that we always shall be detested in France. -Duke Wellington)
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To: LibWhacker

I thought the Cretaceous extinction took about a million years?


48 posted on 07/08/2004 3:40:44 AM PDT by mewzilla
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To: LibWhacker


49 posted on 07/08/2004 3:48:56 AM PDT by angkor
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To: LibWhacker
It's a popular theory on the internet that the huge crater at Chicxulub in the Yucatan, was caused by a spaceship carrying the original neanderthal seedlings. Man was supposed to evolve in a terribly harsh, dinosaur-filled environment - survival of the very fittest. Unfortunately, the crash moved human inception back a few million years.

One unforseen effect of this, because of the easier path, has been the early emergence of the "liberal" gene, which ideally would have been suppressed for a long, long time. Also, one can note that humans were to have started in north america rather that africa. Also, this event gave a big boost to cockroaches and rats, both of which were originally planned to exist in much smaller populations.

50 posted on 07/08/2004 4:02:15 AM PDT by searchandrecovery (Socialist America - diseased and dysfunctional.)
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To: Michael121
He said that there is a little tree frog in S. America and if you change his surrounding temp by a degree it DIES.

Lisa Simpson - "So a screamapillar has decided to inhabit your area. Things you need to know: 1) without constant reassurance it will die 2) it is sexually attracted to fire.

Homer - "Are you sure God didn't want this thing to be extinct!"

51 posted on 07/08/2004 4:19:29 AM PDT by Jonx6
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To: draoi
The chances of a big hit are small but there's always that chance, the planets have swept up most of the rocks flying round the solar system but there will always be rocks out there.

Who would have thought that one of the Planets in our solar system would have experienced multiple hits even during our life times (comet striking Jupiter).

52 posted on 07/08/2004 4:23:49 AM PDT by justa-hairyape
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To: Junior; *crevo_list

Archival ping.


53 posted on 07/08/2004 4:30:14 AM PDT by PatrickHenry (Hic amor, haec patria est.)
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To: swilhelm73
Over a decade of boiling temperatures and a nearly constant fires are rather a more serious problem for plant life...

I searched the article again, and found no reference to a decade of boiling heat. I did find this, and it may have given you that impression with a quick read:
“Scientists have speculated for more than a decade that the entire surface of the Earth below would have been baked by the equivalent of a global oven set on broil.”
I think a few days would be more the case.
54 posted on 07/08/2004 6:07:03 AM PDT by R. Scott (Humanity i love you because when you're hard up you pawn your Intelligence to buy a drink.)
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To: Free Trapper
Why would good,fast carbonized horsemen be a factor?

Three-points for that one :)

55 posted on 07/08/2004 8:28:04 AM PDT by Aracelis
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To: freebilly
Sure, and the animals that burrowed underground or sheltered in water survived how? By eating what?

Cans of Spam.

Just like us.

56 posted on 07/08/2004 8:30:44 AM PDT by Lazamataz ("Stay well - Stay safe - Stay armed - Yorktown" -- harpseal)
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To: Positive
Earth may be a small target, but it has been traveling in a repetitive pattern for billions of years; in the field of trajectory of billions of astronomical projectiles...what are the odds of a hit?

Obviously, 1.0 to 1.0.

;^)

57 posted on 07/08/2004 8:32:13 AM PDT by Lazamataz ("Stay well - Stay safe - Stay armed - Yorktown" -- harpseal)
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To: LibWhacker

I understand that scientists wanted to re-create the original event to verify the events. But they decided not to when they realized that re-creation would involve Michael Moore, a bag of beans, and a whole host of ethical issues.


58 posted on 07/08/2004 8:40:14 AM PDT by Our man in washington
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To: Michael121
If Science was always right then scienctist would always agree. Either evidence says planets were formed one way or another. But then 2 PLanets do not fit into the mix at all.

Science is a process of discovery and refinement. Earlier in our history, people believed that the Earth-centered model for our solar system was accurate. Continued observation and modeling proved that the Heliocentric model to be correct. Hypotheses are brought forward and investigated, few stand the test of time...and aren't you glad of this? Else we would still be using beads, chants and rattles as a first line of defense against disease.

And of course two planets don't fit with our current hypotheses. Actually, I'm surprised more doesn't "fit" with our level of understanding. Did you know how to ride a bicycle the first time you tried? It took numerous falls and scrapes before you learned to keep the thing upright. So it is with Science.

As Stephen Hawking said, "The big bang happened, but can we say that a supreme being did not use that method to "create" the universe?" It is something that must not be left out.

I do not rule out the efforts of a Creator, but I do think He used His own natural laws to bring all into being.

59 posted on 07/08/2004 8:40:42 AM PDT by Aracelis
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To: LibWhacker
It's always amazed me that we could even see something as small as that burning up when it's so darned far away from us

Actually, what is seen is the ionization of the atmosphere.

60 posted on 07/08/2004 8:52:06 AM PDT by cinFLA
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