Age (geology)
| Segments of rock (strata) in chronostratigraphy | Time spans in geochronology | Notes to geochronological units |
|---|---|---|
| | 4 total, half a billion years or more | |
| | 10 defined, several hundred million years | |
| | | 22 defined, tens to ~one hundred million years |
| | | tens of millions of years |
| | | millions of years |
| | subdivision of an age, not used by the ICS timescale | |
A geologic age is a subdivision of geologic time that divides an epoch into smaller parts. A succession of rock strata laid down in a single age on the geologic timescale is a stage.
See also
References
- ↑ Cohen, K.M.; Finney, S.; Gibbard, P.L. (2013), International Chronostratigraphic Chart, International Commission on Stratigraphy.