Neoarchean
| Neoarchean | |||||||||||||
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A reconstruction of the Earth's continents during the middle Neoarchean, c. 2.65 Ga. | |||||||||||||
| Chronology | |||||||||||||
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| Proposed redefinition(s) | 2780–2420 Ma Gradstein et al., 2012 | ||||||||||||
| Proposed subdivisions | Methanian Period, 2780–2630 Ma Gradstein et al., 2012 | ||||||||||||
| Etymology | |||||||||||||
| Name formality | Formal | ||||||||||||
| Alternate spelling(s) | Neoarchaean | ||||||||||||
| Usage information | |||||||||||||
| Celestial body | Earth | ||||||||||||
| Regional usage | Global (ICS) | ||||||||||||
| Time scale(s) used | ICS Time Scale | ||||||||||||
| Definition | |||||||||||||
| Chronological unit | Era | ||||||||||||
| Stratigraphic unit | Erathem | ||||||||||||
| Time span formality | Formal | ||||||||||||
| Lower boundary definition | Defined Chronometrically | ||||||||||||
| Lower GSSA ratified | 1991 | ||||||||||||
| Upper boundary definition | Defined Chronometrically | ||||||||||||
| Upper GSSA ratified | 1991 | ||||||||||||
The Neoarchean (/ˌniːoʊ.ɑːrˈkiːən/ NEE-oh-ar-KEE-ən; also spelled Neoarchaean) is the last geologic era in the Archean Eon that spans from 2800 to 2500 million years ago—the period being defined chronometrically and not referencing a specific level in a rock section on Earth. The era is marked by major developments in complex life and continental formation.