• 20 Videos, Slides, Films

• 13 Historical geology
• 13 History
• 13 Internal structure
• 13 Physical geography
• 13 Plate tectonics
• 5 Geology
• 5 Geology, Structural
• 5 Mantle
• 5 Volcanoes
• 4 Geography
• 4 Natural resources
• 3 Environmental aspects
• 2 Biosphere
• 2 Effect of human beings on
• 2 Energy consumption
• 2 Energy development
• 2 Human ecology
• 2 Hydrology
• 2 Landforms
• 2 Management
• 2 Nature
• 2 Power resources
• 2 Volcanism
• 1 Alps
• 1 Biotic communities

• 20 Films Media Group
• 20 Films for the Humanities & Sciences (Firm)
• 4 Cambridge Educational (Firm)
• 2 Infobase
• 1 EBS Trust (Firm)
• 1 Ethical Markets Media
• 1 Public Broadcasting Service (U.S.)

• 20 English

• 1 California
• 1 Death Valley (Calif. and Nev.)
• 1 Hawaii
• 1 Iceland
• 1 Indian Ocean Region
• 1 Indonesia
• 1 Italy
• 1 Krakatoa
• 1 Krakatoa (Indonesia)
• 1 Rocky Mountains
• 1 Solar system
• 1 Vesuvius (Italy)
• 1 Yellowstone National Park
• 1 Yosemite National Park (Calif.)
• 1 Yosemite National Park Region (Calif.)

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