The age is the fundamental chronostratigraphic unit.
Ages/Stages are formally defined following the indications of the ICS (International Commission on Stratigraphy). More specifically, ages/stages are defined by the GSSP of their base, their top being defined by the GSSP of the overlying age/stage.
Interdisciplinary Links in Citizendium
- Earth science
- Stage (geology)
- Geologic time scale
- Geologic ages of earth history
- Overview of Global Boundary Stratotype Sections and Points (GSSP's)Status on June 2004, compiled by Jim Ogg (ICS Executive Secretary) (2004)
- International Stratigraphic Chart