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Re: paleonet GSA Time Scale again



>GSA has re-posted its 1999 Geologic Time Scale at 
>http://geosociety.org/science/timescale/timescl.pdf
>
>It can be printed from that site.

People might find the International Stratigraphic Chart published by 
the IUGS useful as well.  It can be downloaded from the International 
Commission on Stratigraphy site 
(http://www.micropress.org/stratigraphy/tscale.htm):

http://www.micropress.org/stratigraphy/chart.pdf

It's updated to summer 2001 and includes the current status of formal 
and proposed chronostratigraphic units.

One thing that always bugs me about the GSA chart is that the 
Silurian epochs are mistakenly listed as ages.  Llandovery, Wenlock, 
etc. are epochs and should not have an adjectival ending (e.g., 
"Wenlockian").  They're equivalent, e.g., to Lower, Middle, and Upper 
Devonian, not Emsian, Givetian, etc.  The Silurian ages are 
Sheinwoodian, Homerian, etc.

J