This is 'an explanation of how the local geology of central PA relates to that of the Colorado Rockies and the Alaskan tundra. Dozens of “in-the-field” videos just like this enable students to “accompany” Drs. Alley and Sridhar Anandakrishnan on a kind of virtual field trip through the U.S. National Parks, as well as various other local and regional points of geologic importance, in order to gain a deeper understanding of their planet and Earth systems.'
