Everyday Science · 45 sec
Plate tectonics
The science behind something you encounter, use, or wonder about.
The useful idea
- A moving shell
Tectonic plates are composed of the oceanic lithosphere and the thicker continental lithosphere, each topped by its own kind of crust.
- Three boundaries
Where the plates meet, their relative motion determines the type of plate boundary (or fault): convergent, divergent, or transform.
- Crust returns
Along convergent plate boundaries, the process of subduction carries the edge of one plate down under the other plate and into the mantle.
Why this matters
Look for Plate tectonics the next time you notice this pattern in everyday life.
Try this
Look for Plate tectonics the next time you notice this pattern in everyday life.
Test your recall
Which idea belongs to the explanation of Plate tectonics?
- A moving shell — correct
- Three boundaries
- Crust returns
Tectonic plates are composed of the oceanic lithosphere and the thicker continental lithosphere, each topped by its own kind of crust.