• 40 Videos, Slides, Films

• 21 Geography
• 20 Earth sciences
• 17 Environmental sciences
• 16 Landforms
• 16 Natural resources
• 16 Water use
• 14 Historical geology
• 13 Physical geology
• 11 Study and teaching
• 9 Biotic communities
• 9 Ecological regions
• 9 Ecological zones
• 9 History
• 9 Plate tectonics
• 7 Anthropology
• 7 Biology
• 7 Earth (Planet)
• 7 Methodology
• 7 Research
• 6 Chemistry
• 6 Mantle
• 6 Physics
• 5 Experiments

• 21 Infobase
• 20 Films for the Humanities & Sciences (Firm)
• 12 Camille S. DeBose (Firm)
• 5 PBS (Firm)
• 4 National Geographic Television & Film
• 4 Uniview Worldwide
• 3 BBC Worldwide Ltd
• 3 Cambridge Educational (Firm)
• 1 American Geosciences Institute (Firm)
• 1 Australian Broadcasting Corporation (Firm)
• 1 Espresso TV (Firm)

• 40 English

• 5 Earth (Planet)
• 4 United States
• 1 Arizona
• 1 Atacama Desert
• 1 Atacama Desert (Chile)
• 1 California
• 1 Chile
• 1 Death Valley (Calif. and Nev.)
• 1 Grand Canyon (Ariz.)
• 1 Hawaii
• 1 North America
• 1 Rocky Mountains
• 1 Sahara
• 1 Yellowstone National Park
• 1 Yosemite National Park (Calif.)
• 1 Yosemite National Park Region (Calif.)

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