Segments of rock (strata) in chronostratigraphy | Periods of time in geochronology | Notes |
---|---|---|
4 total, half a billion years or more | ||
12 total, several hundred million years | ||
tens of millions of years | ||
millions of years | ||
smaller than an age/stage, not used by the ICS timescale |
- ^ International Commission on Stratigraphy. "International Stratigraphic Chart" (PDF). Retrieved 2008-06-17.