Standard global stages of the Ordovician System are characterised on separate pages:
Below selected stratigraphic charts are provided for downloading:
Ordovician Chronostratigraphic Chart showing correlation of regional chronostratigraphic schemes with the new global stages and series for the Ordovician System, by Bergstrom, S.M., Xu Chen, Gutierrez-Marco, J.C., and Dronov, A., 2008, Lethaia, DOI 10.1111/j.1502-3931.2008.00136.x.