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re:FAQ (Cenozoic names)

From: tholtz@geochange.er.usgs.gov
 > >
 > >I notes the use of the terms 'Tertiary' and 'Quaternary' which are
 > >sub-eras that stratigraphers are trying not to use anymore.  ...
 > >The 'Tertiary' is now split into two periods: the Palaeogene
 > >Period (65-23.3MYBP) and the Neogene Period (23.3-1.64MYBP).  The
 > >'Quaternary' is now referred to as the Pleistogene Period
 > >(1.64-present).
 > >
 > Unfortunately, the US Geological Survey and other major North American
 > geological bodies still prefer the Tertiary and Quaternary in formal
 > stratigraphy. 

Not only that, but the boundary level is still called the K-T
boundary, so I think it better to use the informal terms in the
FAQ for most purposes, perhaps with a note explaining the rename.

[I mean saying the K-T boundary is the boundary between the
Cretaceous and the Paleogene brings up the question of "why
is the 'T' there?", in addition to the question about the 'K';
let's not confuse beginners more than necessary]

 >  Personally, I think the Cenozoic should be divided into the
 > Paleogene and Neogene, with the Pleistocene and Holocene (which together
 > make the traditional Quaternary) as the two most recent epochs of the
 > Neogene.

I agree here.

In fact I would go further, and merge the Pleistocene into the
Pliocene (as the third sub-epoch or stage).  Too often in discussions
of fossils (especially of apes) and paleoecology I run into the
term "Plio-Pliestocene". This suggests to me that there is not really
an epoch level biotic transition there.

swf@elsegundoca.ncr.com         sarima@netcom.com

The peace of God be with you.