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Re: New Geologic Epoch



> Other proposals to the ICS include mucking about with the
> Carboniferous (again...)

How? Reversing the silly "subera" designation for the Mississippian and the Pennsylvanian that means the Carboniferous now has 5 epochs consisting of 1 stage each (some of them very long!) and 1 epoch consisting of a whopping 2 stages?


> and the Cambrian (again...)

Well, in the Cambrian there isn't a lot to muck about with... 2/3 of the stages and half of the epochs don't even have accepted names yet...


> and (one I would like to see passed!)
> formal reorganization of a Lower (Berriasian-Aptian), Middle
> (Albian-Turonian), and Upper (Coniacian-Maastrichtian) Cretaceous.

I'd love that, too (and the Permian has already undergone the shift from two to three subdivisions), except... there's that mass extinction at the Cenomanian-Turonian boundary, and none at the Turonian-Coniacian one, right?


Could I add changing the Tithonian into the Portlandian, so there can be an actual type locality?

Body stratotypes are no longer used. Instead, boundary stratotypes are used. It's a bit like rank-based vs phylogenetic nomenclature, except that the stratigraphers have (recently) completed the shift. Is the J-K boundary exposed in Portland?


You are, however, right that the Kimmeridgian-Tithonian and the Tithonian-Berriasian boundaries don't have stratotypes yet, though the first has two candidates (http://www.stratigraphy.org/gssp.htm).