Geologic stage

A geologic stage, or simply stage, is a chronostratigraphic unit of geologic time more commonly referred to as an "age" or "geologic age", its geochronologic name equivalent.[1] Please refer to Geologic age or Geologic time scale for more information.

Chronostratigraphic/geochronologic name reference chart.[1]
Rank of Time Unit Chronostratigraphic Name Geochronologic Name
1 - Longest Eonothem Eon
2 Erathem Era
3 System Period
4 Series Epoch
5 - Shortest Stage Age

For Further Reading


  1. 1.0 1.1 International Commission on Stratigraphy."Chapter 9. Chronostratigraphic units" Accessed Nov.12, 2018 [Online]. Available: