In the early 1900s, most geologists thought that Earth's appearance, including the arrangement of the continents, had changed little since its formation. This video segment, adapted from the "Earth Explorer" episode of Discovering Women, describes the impact the theory of plate tectonics has had on our understanding of Earth's geological history, as we have become aware of our planet's ever-changing nature.
This video is available in both English and Spanish audio, along with corresponding closed captions.
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