The Theory of Plate Tectonics was formalized during the 1960's, giving geoscientists a new paradigm with which to explain the observed surface features, geological phenomena, and geologic history of Earth.

The image below shows a digital elevation model of the Himalayas, the tallest mountain range in the world. The Himalayas are the type-example of a Continent-Continent Convergent Plate Boundary. Even as you are reading this, the Himalayas are being uplifted as India collides with southern Asia. This collision is driven by the relative motion of the Indian Plate northward.

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Note how the Himalayas rise rapidly in northern India and the broad uplift of the regions to the north as an elevated plateau. The Himalayas are a complexly folded and uplifted series of mountain ranges - a hint of this structure is evident by examining the gray bands (representing the highest mountains) in the image above.

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A characteristic feature of continent-continent convergent plate boundaries is the occurrence of numerous earthquakes (some of which can attain large magnitudes) but an absence of volcanic activity (unlike other convergent plate margins). The image above shows epicenters of earthquakes across the Himalayan region for a single year. Note the extreme earthquake activity in the western Himalayas.

The Theory of Plate Tectonics provided a more thorough explanation of the causes of earthquakes and mountain uplift in the Himalayas. In a similar way, explanations of geologic phenomena around the world were explained by reference to the Plate Tectonic model of Earth dynamics.

To learn more about Plate Tectonics and how geologists have been able to use this theory to explain much of Earth's history, go the Internet and read "This Dynamic Earth" available from the United States Geological Survey.