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Re: Barun Goyot Formation



At 09:29 AM 12/1/97 +0100, you wrote:
>Is the horizon of the Barun Goyot Formation or "Barungoyotskaya" Svita,
>Omnogov, Mongogolian People's Republic stil in doubt? 
>As i understand most stratigraphers placed it in the late Santonian to
>early Campanian stages of the Cretaceous but Fox 1978 and Liligraven and
>McKenna, 1986 thought it was Maastrichtian. Are there any new data on
>this?

Unfortunately, ALL the Mongolian stratigraphy is in doubt (at least compared
to the North American and European sediments of the Late Cretaceous).

Typically the Djadokhta underlies the Barun Goyot, and the Barun Goyot
underlies the Nemegt, but there is a question as to how much time is
represented by each.  The traditional method ("grade of organization" of the
different dinos and mammals in each) for assigning dates is questionable, to
say the least.  There is the very real possibility that these were
essentially contemporaneous, and represent different facies
(subenvironments: very dry, dry, and somewhat wet, respectively...) of the
same time period.

Part of the AMNH-Mongolian expeditions is to sort out the stratigraphy.

Of course, these are better resolved than the Early and mid-K units of
central Asia, which are really muddled up...

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661