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Re: K-Pg chronology resolution at 500 years?



1) As they say in "Monty Python and the Holy Grail", "It's only a model." :-)

2) Individual beds might have higher resolution, especially in the terrestrial realm. It is discontinuous sedimentation. So don't think of each cm in general = a particular length of time. Think of some beds representing a few days/hours, with long gaps in between.

3) There are beds at well-preserved boundary sections were are very short intervals: after the initial ejecta settled but before the finer particles settled out of the stratosphere.

On 2015-12-30 12:03, Poekilopleuron wrote:
Good day,

I´ve noticed this virtual reconstruction of a post K-Pg environment (
https://www.youtube.com/watch?v=IzzaF7DJbBk ) which is supposed to
take place just five hundred years after the big impact. Given that
during this interval only about one of twenty centuries is preserved
in the fossil record, how could the authors of this research be so
precise in their dating? I thought the best resolution at the end of
the Cretaceous is only about a few thousand years, which equals a few
centimeters/inches in the sediment layer. Thank you in advance for
clarification and I wish all listmembers Happy New Year 2016!

--
Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Geology Office: Geology 4106
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Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661

Faculty Director, Science & Global Change Program, College Park Scholars
http://www.geol.umd.edu/sgc
Fax: 301-314-9843

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
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