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Re: dinosaur survived past asteroid impact

I've not read the paper, so it may be that the news article
misrepresented the research.  But with that disclaimer made, my alarm
bells went off when I read that (A) they have come up with a brand new
way of determining the age of fossil bone, and (B) their new way gives
a new result.  Surely it's most parsimonious to think their method is
Just Plain Wrong?  The way to approach this would be first to use the
new method on fossils of knows ages, to check that it gives results
consistent with better-known methods.  THEN if it shows unexpected
results for some fossils, that would be news.

On 29 January 2011 10:48, David Marjanovic <david.marjanovic@gmx.at> wrote:
> http://www.canada.com/technology/Bone+discovery+suggests+dinosaurs+survived+years+past+meteorite+strike/4187835/story.html
> From there:
>>  "But, clearly, not all species (of dinosaurs) became extinct," said
>>  Heaman. "And so could there be some sort of micro-environment where
>>  these dinosaurs perhaps had an oasis or a haven where they could
>>  survive."
> An oasis or haven that persists for _seven hundred thousand years_, and even
> though a population of sauropods survives in it, no dinosaurs ever spread
> out of it?
> That just doesn't make the slightest ecological sense.
> What I suspect is going on is miscalibration between U-Pb and Ar-Ar or
> something. The age of 65.5 Ma for the K-Pg boundary comes, IIRC, from an
> Ar-Ar analysis; a U-Pb age for the impact is, however, 64.98 +- 0.05 Ma.
> While 64.8 still lies outside that range, it's damn close, and the news
> article doesn't say what the error bar on that age is like.
> And while I am at it, I hate it when news articles are 10 or 15 years behind
> the times:
>>  Recent studies have challenged that theory include some suggesting a
>>  series of meteorite impacts caused the dinosaurs to disappear and
>>  others positing massive volcanic eruptions that triggered deadly,
>>  planetwide climate disturbances.
> <wince> <wail>