Observe how volcanoes shape the Earth's surface through continual plate movement. Hear about different volcano types, including shield and composite (stratovolcano), and the effects of differing lava composition. Learn how volcanoes can be both beneficial and harmful to humans and the environment.

Originally released by National Geographic, 2007. Streaming video file encoded with permission for digital streaming by Infobase on April 07, 2015.

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