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Precambrian
Archean Eon
Eon
Proterozoic Eon
Geologic Time
Phanerozoic Eon
Rock (mineral)
climate of Precambrian
dating methods
Earth history
life during the Precambrian
natural features formed during Precambrian
Period (geologic time)
Period (geologic time)
, unit of time that geologists use to divide the earth’s history. On the geologic time scale, a period is longer than an epoch...
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