USGS - science for a changing world

Science Topics

Maps, Imagery, and Publications Hazards Newsroom Education Jobs Partnerships Library About USGS Podcasts/RSS

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

Metadata as [FGDC] - [XML] - [ISO]

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Ask USGS