RE: Geological timescale

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> David Marjanovic
>
> > So have we seen the last of Tertiary and Quaternary?
>
> Yes.

As Fangorn says, let's not be too hasty.  Almost all the planet had already
abandoned the T and the Q a decade or three ago.  However, the US Geological
Survey still accepts them (as well as the Mississippian and Pennsylvanian as
formal periods), so expect to see these remain in the American technical
literature, unfortunately.

> And the Vendian has been abandoned
> http://www.stratigraphy.org/prec.htm. :.-(

That was a decision I had already heard about.  Bother.  I still prefer
Vendian to Ediacaran.

> It's interesting they didn't introduce
> the Middle
> Cretaceous; as used in Glut's Supplement 3 (Albian + Cenomanian), it would
> make quite some sense, being bounded by two noteworthy mass extinction
> events.

The Middle Cretaceous has NEVER been formally defined and accepted by
stratigraphers, so Glut was rather foolishly following a number of
vertebrate paleontologists...

> BTW, the Holocene now began 11,500 years ago, not 10,000.
> http://www.stratigraphy.org
>
> I still haven't found why the K-T boundary is given as 65.5 +- 0.3. I
> suspect the discrepancy between U/Pb in zircons vs Ar...

As I said, Wait For The Paper... I mean, Book.

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796