This is a drawing of the Earth's lithosphere.
Click on image for full size

Clues to Plate Movements

Many kinds of surface features are clues to a sliding lithosphere.

Two types of features can form when plates move apart. At ocean ridges, the crust splits apart to make room for molten mantle rock. Continental rifts form when a continent begins to split apart.

When two plates move towards each other, sometimes one of the plates is forced to go down into Earth’s hot interior at a subduction zone and volcanoes form nearby. Or, if neither plate is subducted, the two will crash into each other forming huge mountains.

These features are special clues that prove our planet's surface is in motion. There are only a few other planets that have clues like these.


Last modified March 2, 2008 by Randy Russell.

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