PBS
Pbs Learning Media: The Grand Canyon: Its Youngest Rocks
This video segment adapted from NOVA features the youngest rock formations in the Grand Canyon, lava dams, and how they are subject to the eroding power of water.
PBS
Pbs Learning Media: The Grand Canyon: Ancient Mountains
This video segment adapted from NOVA features the twisted and melted forms of the Grand Canyon's oldest rocks, the 1.7-billion-year-old Vishnu Schist.