The Statherian (IPAEng|stəˈθɪəriən, _el. "statheros", meaning "stable, firm") is the final
geologicperiod in the PaleoproterozoicEra 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.
supercontinentColumbia formed at the beginning of this period.
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