| Comprehending Geological Time [ Teens/Mature Teens ] - An interactive tool to calculate time periods and human history in terms of different measurement scales such as a meter, a day or a million years. http://www.athro.com/geo/hgfr1.html |
| Dr. Bob's Geologic Time Page [ Mature Teens ] - Basic information about the geologic time scale and mnemonics to help remember the various periods and epochs. http://oldsci.eiu.edu/geology/jorstad/geoltime.html |
| Earth Floor: Geologic Time [ Teens/Mature Teens ] - Explains how the age of the earth is divided up into periods of time, and provides simple definitions and illustrations of the different names. http://www.cotf.edu/ete/modules/msese/earthsysflr/geotime.html |
| Geological Time Line [ Teens/Mature Teens ] - A simple chart provides links to further details of each era, and an interactive feature allows users to see global shifts and milestones. http://www.bobainsworth.com/fossil/timeline.htm |
| Life Through Geologic Time [ Kids/Teens/Mature Teens ] - A pictorial history of life on Earth, with events and fossils linked from the relevant period or epoch. http://www.carlwozniak.com/earth/Life.html |
| Web Geological Time Machine [ Kids/Teens/Mature Teens ] - A simple table of the different time periods contains links to details of the rocks, fossils and locations of each one. http://www.ucmp.berkeley.edu/help/timeform.html |