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GSA Geologic Time Scale

The time scale printed in April/May 2009 GSA Today contained a spelling error (under ORDOVICIAN: HIMANTIAN should be HIRNANTIAN). This page contains the corrected version.
[ read about the changes  |  view printable PDF ]

Note that the authors are still accepting comments on the overall content of time scale. Offer your comments or join in the discussion on GSA's Facebook page.

updated 8 April 2009

Geologic Time Scale

Other versions: 2012 | 2009 | 1999 | 1983


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