Tuesday, July 27, 2010

USGS Publishes Updated Geological Divisions

3 comments:

chris y said...

If they're going to all that trouble, I wish they'd redefine the Phanerozoic to include the Ediacaran. It's a glaring anomaly otherwise.

220mya said...

The problem is that this USGS timescale is actually more out-of-date than the one released by GSA last year:

Walker, J. D., and J. W. Geissman. 2009. GSA geologic time scale. GSA Today 19:60-61.

As Chris notes, the new USGS timescale omits the Ediacaran and fails to revise the ages for the Late Triassic stages.

Its all too bad, because I've seen a variety of blogs talking about this being the 'newest' timescale.

220mya said...

My bad - I see the Ediacaran is actually there. Chris - it is in the Proterozoic, where it should be.