What is deep time?

people walking in front of native American dwellings
Anna Brendle

Richard Alley, Evan Pugh professor of geosciences, led an expedition of students through 12 National Parks of the southwestern United States in May 2004.

Richard Alley explains deep time and how it tells the story of our planet in the accompanying videos.

Richard Alley, Ph.D., is Evan Pugh professor of geosciences in the College of Earth and Mineral Sciences, rba6@psu.edu. The expedition was sponsored by CAUSE (Collaborative Active Undergraduate Student Experience), an annual course offered by the College of Earth and Mineral Sciences.

Last Updated May 25, 2005