Plentiful and plain shale plays vital role on Earth
1 of 1
This outcropping of the Marcellus formation near Williamsport, Pa., shows shale that could be rich in natural gas.
Photos: Northwestern Hawaiian Islands Expedition: Sept. 30
Photos: Animal Farm: Sept. 20
Photos: H.S. Volleyball: Kam vs. Iolani, Sept. 30
More Photo Galleries »