There are two main geological layers in Petrified Forest National Park, the Mio/Pliocene Bidahochi Formation and the Late Triassic Chinle Formation. These formations are further separated into members,
Did You Know?
Petrified wood at Petrified Forest National Park is almost solid quartz, weighing in at 168 pounds per cubic foot. It's so hard, you can only cut it with a diamond tipped saw! More...