Skip to comments.Study: Dinosaurs Died Within Hours After Asteroid Hit
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.
Einstein was Einstein because he entertained the possibility that Velikovsky was right. I have no doubt that Velikovsky was a smarter man than you are, or me for that matter. I consider "dolts" those who blindly follow the pack and never ask questions...have you ever asked yourself (i know, its hard in your case) *WHY* the most famous scientist in 1953 would even give Velikovsky the time of day? i'll tell you why -- because Velikovsky had the same kind of enquiring mind that Einstein did, and Einstein respected that...
One needs to be very, very careful with how one approaches "science", since scientists are just human beings -- with science, there is a very strong tendancy for anal retentive personalities to engage in the field -- for many, science is admired as a father/authority substitute, the same tendency many had towards supported Adolf Hitler or the tendency to support ANY person or institute in power.
Velikovsky was more of a Weekly World News kind of guy.
Interesting that there are no apparent signs of this.. must be a faith thing..
I don't suppose your vast and Enquiring® mind could entertain the possibility that Einstein would be concerned about a popular best seller going unchallenged. You could, of course, admit that you were wrong about Einstein and velikovsky, but that would require a modicum of honesty.
Velikovsky was a very learned man willing to look at things in a new light, just as did Einstein, who was not the anal retentive type at all, unlike some other defenders of science...
July 8, 1946
> Dr. Immanuel Velikovsky
> 526 West 113 Str.
> New York City
> Dear Mr. Velikovsky:
> I have read the whole book about the planet Venus.
> There is much of interest in the book which proves that
> in fact catastrophes have taken place which must be
> attributed to extraterrestrial causes. However it
> evident to every sensible physicist that these catast-
> rophes can have nothing to do with the planet Venus and
> that also the direction of the inclination of the
> terrestrial axis towards the ecliptic could not have under-
> gone a considerable change without the total destruction
> of the earth's entire crust. It were best in my opinion
> if you would in this way revise your books, which contain
> truly valuable material. If you cannot decide on this,
> then what is valuable in your deliberations will become
> ineffective, and it would be difficult finding a sensible
> publisher who would take the risk of such a heavy setback
> upon himself.
> I tell you this in writing and return to you your manu-
> script, since I will not be free on the considered days.
> With friendly greetings, also to your daughter,
You mistake politeness for credulity. Einstein's letter is a bolw-off, rejecting everything about Velikovsky except for the obvious fact that there have been catastrophes in earth's history. Velikovsky was wrong about the dates, causes and scopes of the catastrophes, but then nobody's perfect.
Velikovsky was one of the first to propose earth changes due to catastrophic astronomical events, something we are all to well aware of now given the increased awareness of ELE events and the dangers inherent to asteroid strikes...and AE gives him credit for that right up front.
The truth of the matter is that Einstein considered Velikovsky a bit of a soul mate:
>Einstein often used the term "moshogoim" in reference to himself AND
>Velikovsky, the intent being not so much the literal one as "outsiders,
>wildmen" and so forth.
As I said, Velikovsky was right about everything except the dates, causes and sizes of his catastrophes. Perhaps he deserves some credit for forcing attention to catastrophes, but he deserves zero credit for scientific analysis.
And you persist in refusing to admit you were rong about the book introduction.
Check your facts first. I never claimed anything about a book introduction...
Science and engineering deals with facts and conclusions based on clear thinking and trained observations, including last, but not least, with the use of clear and unambiguous language.
The asteroid could not have hit Chicxulub, since that is the name given to the crater resulting from the impact.
What kind of scientific morons are they cranking out these days?
High metabolisms. Needed to breathe frequently, therefore needed to surface, therefore needed to transit the boiling hot surface to get to the air, and were unable to shelter in deeper water.
Tunnel dwellers are accustomed to lower oxygen and higher carbon dioxide in poorly ventilated burrows...
Letter from Einstein to Velikovsky:
July 8, 1946
Dr. Immanuel Velikovsky
526 West 113 Str.
New York City
Dear Mr. Velikovsky:
I have read the whole book about the planet Venus. There is much of interest in the book which proves that in fact catastrophes have taken place which must be attributed to extraterrestrial causes. However it is evident to every sensible physicist that these catastrophes can have nothing to do with the planet Venus and that also the direction of the inclination of the terrestrial axis towards the ecliptic could not have undergone a considerable change without the total destruction of the earth's entire crust. It were best in my opinion if you would in this way revise your books, which contain truly valuable material. If you cannot decide on this, then what is valuable in your deliberations will become ineffective, and it would be difficult finding a sensible publisher who would take the risk of such a heavy setback upon himself.
I tell you this in writing and return to you your manuscript, since I will not be free on the considered days.
With friendly greetings, also to your daughter,
Should be "I apologise". My wireless keyboard needed new batteries. It has been skipping characters.
You are wrong. See T. Rex and the Crater of Doom. The clearest evidence of an abrupt extinction is the abrupt and total change in the foramintifera.
Like that's never happened to any of us.
Glad you can laugh about if after a bit of sleep...
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