Statherian

The Statherian (pronounced /stəˈθɪəriən/, Greek: statheros, meaning "stable, firm") is the final geologic period in the Paleoproterozoic Era and lasted from 1800 Ma to 1600 Ma (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically.

During this period the first complex single-celled life appeared.

The period is characterized on most continents by either new platforms or final cratonization of fold belts.

The supercontinent Columbia formed at the beginning of this period.

References

* "Statherian Period". GeoWhen Database. http://www.stratigraphy.org/geowhen/stages/Statherian.html. Retrieved January 5, 2006.
* James G. Ogg (2004). "Status on Divisions of the International Geologic Time Scale." ([ – Scholar search). Lethaia 37: 183–199. doi:10.1080/00241160410006492. http://www.stratigraphy.org/precambrian/Ogg_2003.pdf.