Neoarchean

Neoarchean
2800 – 2500 Ma Pha. Proterozoic Archean Had.
A reconstruction of the Earth's continents during the middle Neoarchean, c. 2.65 Ga.
Chronology
−2800 — – −2750 — – −2700 — – −2650 — – −2600 — – −2550 — – −2500 — A r c h e a n ♇ Mesoarchean Neoarchean Paleoproterozoic   ← Prokaryotic Microbes appeared on land ← Supercontinent Kenorland forms Events of the Neoarchean. Axis scale: millions of years ago.
Proposed redefinition(s)	2780–2420 Ma Gradstein et al., 2012
Proposed subdivisions	Methanian Period, 2780–2630 Ma Gradstein et al., 2012 Siderian Period, 2630–2420 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[citation needed]
Upper boundary definition	Defined Chronometrically
Upper GSSA ratified	1991[citation needed]

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.