Extinction of dinosaurs and so on  

SINE

Meteor debris is everywhere as much as in the hole.

Here is what your Jet Propulsion Laboratory says:


Jet Propulsion Laboratory, 3/6/2003

NASA retrieved and edited 11 12 2008

"Studies … of the magnetic and gravity data plus analysis of rocks and ocean sediments published in 1991 helped convince the scientific world that Chicxulub was the site of the impact that sent life on Earth in a new direction, from the age of dinosaurs to the age of mammals.

Much about Chicxulub remains mysterious. ‘We don't know exactly how the impact caused the mass extinctions,’ says scientist Pope. ‘We believe it did, but we don't know what the "kill mechanism" was. One theory is that the impact threw up so much dust into the atmosphere that it obscured the Sun and stopped plants from growing. Another is that the sulfur released by the impact lead to global sulfuric acid clouds that also blocked the Sun and fell as acid rain. Global wild fires triggered by the atmospheric reentry of red-hot debris from the impact are another possibility.’

Since 2003 when your Jet Propulsion Laboratory said this, some others concluded this particular collision was NOT the cause of mass extinctions that occurred in a relatively short time.

Still quoting:


Wikipedia retrieved and edited 11/12/2008:

"Some, including paleontologist Robert Bakker, argue that such an impact would have killed frogs as well as dinosaurs, yet the frogs survived the extinction event. Gerta Keller of Princeton University argues that recent core samples from Chicxulub prove the impact occurred about 300,000 years before the mass extinction, and thus could not have been the causal factor.

The main evidence of such an impact, besides the crater itself, is contained in a thin layer of clay present … across the world … that contained an abnormally high concentration of iridium … [whose source could well be iridium-rich meteors.] It was hypothesised that the iridium was spread into the atmosphere when the impactor was vaporized and settled across the Earth's surface among other material thrown up by the impact, producing the layer of iridium-enriched clay.

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