Moving Plates

Our planet is built in layers, beginning with a thin outer shell called the crust. Beneath it lies the mantle, which is solid near the top but turns soft farther down. At the center sits the core, with a soft metal outer section and a solid metal middle.

The crust and the upper part of the mantle together break apart into large sections known as plates. These plates rest on the softer magma of the lower mantle, and as that magma moves, it carries the plates along. When one plate pushes against another, mountains can rise, and earthquakes and volcanoes can form.

When plates slide past each other in opposite directions, earthquakes can occur. Where plates pull apart, magma rises into the gap and cools into new crust, and this process can also trigger volcanoes and earthquakes. Scientists trace the edges of plates by noting where mountains, earthquakes, and volcanoes cluster.

This 24-page book uses bright illustrations and diagrams to explain these ideas and includes a pronunciation guide. It is suited to a reading level of 1 to 3 and an interest level of 2 to 5.