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                            Ordovician III ICS Stage
 
                     From 471.8 +/- 1.6 To 468.1 +/- 1.6 Ma
 
  Start Defined By:  Conodont, potentially lowest occurrence of Protoprioniodus 
     aranda or of Baltoniodus triangularis.
  End Defined By:  Graptolite, lowest occurrence of Undulograptus 
     austrodentatus.
 
  Start Based On:  Gradstein, Ogg, Smith, _A Geologic Time Scale 2004_
  End Based On:  Gradstein, Ogg, Smith, _A Geologic Time Scale 2004_
 
  Comment:  Official ICS name not yet decided.
 
 -- Overlaps With --
  Australian Stage: Chewtonian (473 - 471)
 
 -- A Substage of --
  Eon:                  Phanerozoic       (542 - -5.5012e-005)
  Era:                  Paleozoic         (542 - 251)
  Period:               Ordovician        (488.3 - 443.7)
  Epoch:                Middle Ordovician (471.8 - 460.9)
  General Stage:        Llanvirn          (471.8 - 464)
  North American Stage: White Rockian     (471.8 - 462)
 
 -- Preceeded By --
  Epoch:                Early Ordovician (488.3 - 471.8)
  ICS Stage:            Arenig           (478.6 - 471.8)
  Chinese Stage:        Dawanian         (472 - 471.8)
  European Stage:       Fennian          (473.5 - 471.8)
  North American Stage: Ibexian          (491 - 471.8)
  North American Stage: Cassinian        (473 - 471.8)
 
 -- Followed By --
  ICS Stage: Darriwilian (468.1 - 460.9)
 
 -- Contains the Following Stages --
  Australian Stage: Castlemanian (471 - 470)
  Australian Stage: Ypeenian     (470 - 468.1)
 
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