[meteorite-list] 'Dinosaur-killing' Impact Did Not Start Global Wildfires

From: E.P. Grondine <epgrondine_at_meteoritecentral.com>
Date: Thu, 26 Feb 2009 20:08:10 -0800 (PST)
Message-ID: <711498.78865.qm_at_web36901.mail.mud.yahoo.com>

Hi Ron -

Did Morrison referee this one?

http://www.nature.com/news/2009/090223/full/news.2009.112.html

"The impact of a huge asteroid or comet"

uhhh - the impactor is known to have been a comet, and that has been known for quite some time.

"at the end of the Cretaceous period 65 million years ago is generally held responsible for the sudden demise of 60???80% of all species on Earth. But new results challenge the common idea that the extinctions were partly caused by global wildfires triggered by the violent impact."

"Claire Belcher and colleagues at Royal Holloway University of London in
Surrey, UK, say in a paper in the Proceedings of the National Academy of
Sciences USA that the widespread soot deposits in sedimentary
rocks formed at the time of the putative impact are not, as previously
asserted, evidence of runaway fires caused by the meteorite's impact."

How about soot from the comet itself?

"The researchers think the soot comes from combustion of hydrocarbons
within the rocks of the impact site itself"

How about soot from the comet's hydrocarbons?

However you work the dynamics of the KT impact, you end up with a rain of molten impact debris which was perfectly capable of setting the surface of the Earth on fire. I suspect this team's measurement or laboratory techniques.

E.P. Grondine
Man and Impact in the Americas






      
Received on Thu 26 Feb 2009 11:08:10 PM PST