What is Geologic Time?
http://web.archive.org/web/20070703102056/http://wrgis.wr.usgs.gov/docs/usgsnps/gtime/index.html

USGS


This USGS site employs graphics and text to explain geological time. The different geological eons, eras, epochs and periods are defined and put into perspective. The site also provides links to many terms and concepts for further exploration.


Resource Type: Scientific Resources:Overview/Reference Work, Audio/Visual:Images/Illustrations