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Geology · Beginner
Plate Tectonics Fundamentals
Introduction
A planet in motion
Look at a world map. Notice how South America and Africa look like they could fit together? In 1912, meteorologist Alfred Wegener proposed they once did — part of a single supercontinent called Pangaea.
His idea was rejected for 50 years. He had no mechanism — no way to explain HOW continents could move. Then in the 1960s, seafloor mapping revealed an entirely new story: Earth's surface is broken into about a dozen rigid plates floating on a hot, flowing mantle.
This is plate tectonics — the theory that unifies nearly all of geology.
Key Terms — tap to expand