Plate Tectonics for Kids: Why Continents Move

Plate tectonics for kids: Earth's surface is broken into about 15 large pieces called tectonic plates that float on the hot, flowing mantle below. These plates move very slowly — about 2-10 cm per year (as fast as your fingernails grow!). When plates push together, pull apart, or slide past each other, they cause earthquakes, create mountains, and build volcanoes.

Introduction

Imagine Earth's surface as a giant cracked eggshell floating on a soft interior. The pieces of the shell are constantly moving, bumping into each other, and pulling apart. This movement is responsible for some of Earth's most dramatic events!

Let's find out why the ground beneath us is always moving.

What Happens When Plates Meet?

• Convergent (Crashing Together): Creates mountains and volcanoes. The Himalayas formed when India crashed into Asia!
• Divergent (Pulling Apart): Creates new crust and rift valleys. The Mid-Atlantic Ridge is where plates are pulling apart under the ocean.
• Transform (Sliding Past): Creates earthquakes. The San Andreas Fault in California is a transform boundary.

Pangaea: The Supercontinent

About 250 million years ago, all the continents were joined together in one giant supercontinent called Pangaea (pan-JEE-uh). Over millions of years, Pangaea broke apart and the pieces slowly drifted to where they are today.

You can see evidence of this yourself! Look at a map — notice how the east coast of South America fits perfectly into the west coast of Africa? They were once connected! Scientists also found matching fossils and rocks on continents that are now separated by oceans.

Try This!

Print or trace a world map and cut out the continents. Try fitting them together like a puzzle to recreate Pangaea. You'll see that South America and Africa fit together almost perfectly! This is one of the first clues scientists found about plate tectonics.

Cool Facts

• There are about 15 major tectonic plates and several smaller ones
• Plates move 2-10 cm per year — about as fast as your fingernails grow
• The Himalayas are still rising by about 5 mm per year as India pushes into Asia
• The Atlantic Ocean is getting wider by about 2.5 cm per year
• About 250 million years from now, the continents may merge again into a new supercontinent!

Did You Know?

• Iceland is one of the few places where you can see a mid-ocean ridge above the water — you can even walk between two tectonic plates there!
• Los Angeles and San Francisco are on different plates — in about 15 million years, they'll be neighbors!
• The theory of plate tectonics was not accepted by most scientists until the 1960s

Wrap Up

Plate tectonics is the reason we have mountains, volcanoes, earthquakes, and even different continents. Earth's surface is like a slow-motion puzzle that is always rearranging itself. Understanding plate tectonics helps us understand how our planet has changed and will continue to change.