Living Rock: Introduction to Earth's Geology: The "Living Rock" DVD, a joint publication of the US Geological Survey and Alpha DVD, is a one hour educational program about the Earth's geology. Targeted at High School grade levels, Living Rock introduces students to such geology concepts as: Geologic Time; Continental Crust; Plate Tectonics; Volcanic Activity; Earthquakes; Subduction Zones; Erosion and Glaciers.