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Divisions of Geologic Time - Major Chronostratigraphic and Geochronologic Units

A summary of the divisions of geologic time intended to provide a consistent time scale to be used in communicating ages of geologic units in the United States.

by USGS Geologic Names Committee
U.S. Geological Survey Fact Sheet 2007-3015
This publication is available only as a PDF document.
Related topics:
Geochronology, Geologic history, Geologic time periods, Geologic time scales
Alternative formats of this information:
Compatible standard Format
CCM of Project Open Data JSON
ISO 19115 XML
USGS Publications Warehouse [Citation page] - [JSON]

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