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You are here: Categories > Time periods > Geologic time periods > Precambrian

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Divisions of geologic time-major chronostratigraphic and geochronologic units [More info]
Revised geologic time scale indicating the ages of the lower bounds of chronostratigraphic and geochronologic units as they are currently known. Modifications to those ages made since the previous time scale was released (2007) are clearly marked.
PDF Precambrian Time - The Story of the Early Earth [More info]
Explains what we know about the early history of the earth and how we study the deposits formed during that time to understand the formation of the earth and life.
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