Tour of geologic time

Phanerozoic Cenozoic Mesozoic Paleozoic Precambrian Proterozoic Archean Hadean

Here you can journey through the history of the Earth, with stops at particular points in time to examine ancient life, climates, and geography. You might wish to start in the Cenozoic Era (65.5 million years ago to the present) and work back through time, or start with Hadean time (4.6 to 4 billion years ago)* and journey forward to the present day — it's your choice. Ways to begin your exploration: Use the links in the time scale at left. Explore a specific period of time that interests you. Learn about the history of the geologic time scale. Find out more about plate tectonics, an important geological concept in any time period!

* Dates from the International Commission on Stratigraphy's International Stratigraphic Chart, 2009.
 
Anthony R. Fiorillo created the original page, 12/13/1993; P. David Polly added graphics, 12/6/1993; Allen G. Collins added the time machine, 11/26/1994; Brian R. Speer rewrote text and added to geologic chart, 3/8/1997; Colleen Whitney constructed a new intro page, 5/2000; Dave Smith made modifications to the intro page and added a new banner, 7/7/2000; Dave Smith simplified the page and adapted it to the new site format, 6/2011