• 8 Videos, Slides, Films

• 2 DVDs

• 7 Historical geology
• 6 History
• 6 Plate tectonics
• 4 Continental drift
• 3 Volcanoes
• 2 Geology
• 2 Trenches
• 1 Asteroids
• 1 Collisions with Earth
• 1 Glacial epoch
• 1 Gold
• 1 Historical geography
• 1 Origin
• 1 Tsunamis
• 1 Volcanism

• 8 Johnson, Corey, 1961-
• 2 Arts and Entertainment Network
• 2 History (Television network)
• 2 New Video Group
• 2 Pioneer Productions
• 1 Beckham, Mike
• 1 Johnson, Kathryn (Director)
• 1 Scarrott, Rachel
• 1 Strange, Robert
• 1 Werbe, Susan

• 8 English

• 7 Earth (Planet)
• 3 Pacific Area
• 2 Great Lakes (North America)
• 2 Iceland
• 2 Krakatoa (Indonesia)
• 2 Rocky Mountains
• 2 San Andreas Fault (Calif.)
• 1 Alps
• 1 Atacama Desert (Chile)
• 1 Death Valley (Calif. and Nev.)
• 1 Everest, Mount (China and Nepal)
• 1 Grand Canyon (Ariz.)
• 1 Hawaii
• 1 Ness, Loch (Scotland)
• 1 New York
• 1 New York (N.Y.)
• 1 New York (State)
• 1 North America
• 1 Rocky Mountains Region
• 1 Sahara
• 1 Saint Helens, Mount (Wash.)
• 1 Vesuvius (Italy)
• 1 Yellowstone National Park
• 1 Yosemite National Park (Calif.)

• 2 Nature television programs
• 2 Nonfiction television programs
• 2 Science television programs
• 2 Television programs
• 2 Television series
• 2 Video recordings for the hearing impaired

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