Not by Fire but by Ice


Discover What Killed the Dinosaurs . . . and Why it Could Soon Kill Us



Maybe an Asteroid didn’t Kill the Dinosaurs

New study lends credence to ice-age theory


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27 Apr 09 - Some 65 million years ago — as school children are now taught — an asteroid struck the earth, deposited a thin layer of iridium around the world, and sent up a cloud that blocked the sun and cooled the planet. That, in turn, wiped out the dinosaurs and made way for the rise of mammals.

Below the layer of iridium, paleontologists find a riot of thriving species in the fossil record; above the layer, more than 65% of all species disappear.

But a new study published in the Journal of the Geological Society shows that the asteroid impact and dinosaur extinction may have occurred hundreds of thousands of years apart.

The controversial paper was written by geoscientists Gerta Keller of Princeton University and Thierry Addate of the University of Lausanne, in Switzerland.

Analyzing fossils at numerous sites in Mexico, including El Pen, near the supposed impact crater, Keller and Addate counted 52 distinct species just below the iridium layer — and the same 52 species above it. The die-offs didn’t appear until 30 feet higher in the sedimentary record, some 300,000 years later.

"Not a single species went extinct as a result of the Chicxulub impact," says Keller.

So if the Chicxulub asteroid didn't kill the dinosaurs, what did?

It is possible that some kind of atmospheric haze blocked the sun, making the planet too cold for the dinosaurs, Keller and Addate agree. But it didn't have to come from an asteroid. Rather, they say, the source might have been massive volcanoes, like the ones that created India’s Deccan Traps.

            I agree with Keller and Addate that the Deccan Traps*  could have
            triggered the dinosaur extinction, except I don’t think the two geo-
            scientist's study goes far enough. 

            According to paleontologist Dewey McLean (personal communication),
            "a good portion of the Deccan Traps and related volcanism was

            As the lava poured into the seas, its temperature would have measured
            2,150 degrees hot, ten times the boiling point. The oceans must have
            boiled, literally boiled, sending untold amounts of moisture into skies
            already cooled by the above-water volcanoes, inevitably leading to an
            ice age.

            Warmer oceans and colder skies, a deadly combination . . . which is
            what I propose in Not by Fire but by Ice.

See entire article by Jeffrey Kluger:,8599,1894225,00.html?cnn=yes
Thanks to Steve Zelinski for this link

                    * More than two million cubic kilometers of lava poured out of the
                               Deccan Traps at the K-T boundary, smothering 220,000 square miles
                               of western India - about a sixth of the country - under successive
                               layers of lava up to a mile-and-a-half deep.





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