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                                Oligocene Epoch
                                   (Midwayan)
 
                     From 33.9 +/- 0.1 To 23.03 +/- 0.05 Ma
 
  Start Defined By:  Planktonic foraminifer, extinction of Hantkenina.
  End Defined By:  Base of magnetic polarity chronozone C6Cn.2n; lowest 
     occurrence of planktonic foraminifer Paragloborotalia kugleri; near 
     extinction of calcareous nannofossil Reticulofenestra bisecta (base Zone 
     NN1).
 
  Start Based On:  Gradstein, Ogg, Smith, _A Geologic Time Scale 2004_
  End Based On:  Gradstein, Ogg, Smith, _A Geologic Time Scale 2004_
 
 -- Overlaps With --
  Australian Stage:     Aldingian   (36 - 33)
  Australian Stage:     Longfordian (27.5 - 16.5)
  Californian Stage:    Refugian    (35 - 33.5)
  Californian Stage:    Zemorrian   (33.5 - 22)
  North American Stage: Chadronian  (37 - 33.5)
  North American Stage: Arikareean  (30.5 - 19)
 
 -- A Substage of --
  Eon:              Phanerozoic (542 - -5.5012e-005)
  Era:              Cenozoic    (65.5 - -5.5012e-005)
  Period:           Paleogene   (65.5 - 23.03)
  Informal Sub-era: Tertiary    (65.5 - 1.806)
 
 -- Preceeded By --
  Epoch:     Eocene      (55.8 - 33.9)
  Sub-Epoch: Late Eocene (37.2 - 33.9)
  ICS Stage: Priabonian  (37.2 - 33.9)
 
 -- Followed By --
  Period:            Neogene       (23.03 - -5.5012e-005)
  Epoch:             Miocene       (23.03 - 5.332)
  Sub-Epoch:         Early Miocene (23.03 - 15.97)
  ICS Stage:         Aquitanian    (23.03 - 20.43)
  New Zealand Stage: Otaian        (23.03 - 21)
 
 -- Contains the Following Sub-Epochs --
  Sub-Epoch: Early Oligocene (33.9 - 28.4)
  Sub-Epoch: Late Oligocene  (28.4 - 23.03)
 

This page was automatically generated from the GeoWhen database (version 1.1.0).  Please read the introduction regarding the accuracy and reliability of this information.  Comments, corrections, and additions can be sent to geowhen@robertrohde.com.  References to published academic literature are preferred.

Introduction

Geologic Timeline
(No Stages)

Geologic Timeline
(With Stages)

A-Z Stage List

Regional Information

Download Files


© 2003-2005 GeoWhen Database
Prepared By Robert A. Rohde


This page was last updated on Tuesday, January 18, 2005.