Is the ground under us made of giant pieces?

Think about digging in a sandbox or a garden. You can feel the dirt, cool and crumbly between your fingers. That dirt sits on top of much more ground, going down and down. So is the ground under us made of giant pieces?

Under the soft dirt lies hard, solid rock. If a team of diggers kept going, past roots and worms, their shovels would hit stone. The dirt is only a thin cover, and the rock holds it up like a floor.

This hard rock forms the outside of our whole Earth, like a thin, firm shell. Think of the crust on a loaf of bread, thin and firm around the outside. Earth's rocky shell is thin too, compared with the whole huge planet.

The rocky shell wraps all the way around Earth and covers everything. It lies under the fields, under the cities and under the deep oceans too. Is it one whole shell, like the peel on an orange, or is it cracked into parts?

It is cracked! Earth's rocky shell is broken into giant pieces called plates, which means huge slabs of rock that fit together. The big ones stretch wider than whole countries.

Earth has seven giant plates and many smaller ones. Right now, your home and your bed sit on one of these plates too.

The plates fit side by side, like pieces of a giant jigsaw puzzle. Where two plates meet, there is a long seam in the rock. Deep oceans hide many of these seams, and soil and trees cover the rest, so you do not see them on a walk in the park.

Plates. Yes, the ground under us is Earth's hard rocky shell, and it is broken into giant plates that fit together like a puzzle.

Sleep tight tonight, resting safe and cozy on your own giant piece of Earth.