In article .com,
Denny wrote:

While the geologic record for Chicxulub is well documented the
commonly known "fact" that this caused the dinosaurs to die out is
debatable since their demise was spread over millions years covering
both pre and post Chicxulub impact; not just over a few weeks or
months, or even a few hundred years..

Oh, I agree... that's why I used the phrase "coup de grace" and "most
of the dinosaurs". There's good evidence that there was a lot of
ecological stress from other causes (e.g. volcanism, change in ocean
circulation patterns, etc.) which had been reducing the diversity and
population of many Dinosauria for quite some time before the Chicxulub
impact. And, of course, mainstream scientists now believe that one
branch of the Dinosauria survived right up until present times.

The seabed record does show Chicxulub caused a drop in temperatures
for some time period and significant species losses..

I've seen one report which indicates that the area in which this
asteroid hit consisted of rock which was unusually rich in sulphur,
thus leading to a more severe sulphate-particle "nuclear winter"
effect than what might have occurred if the impact had been elsewhere.

One way or the other, it was probably a rather rotten time to be on
this particular planet.

There have been
a number of other massives die offs seen in the fossil records that
are not well explained and not all can be tied to an impact...

Agreed. Life, and death, are both rather complex matters :-)

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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