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Related to Archean eon: Proterozoic eon, Phanerozoic eon
Archean eon:see PrecambrianPrecambrian,
name of a major division of geologic time (see Geologic Timescale, table), from c.5 billion to 570 million years ago. It is now usually divided into the Archean and Proterozoic eons. Precambrian time includes 80% of the earth's history.
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