Slow Motion Puzzle! Why Do Earth's Plates Move?

What Crafty Clover says in this video

Intro

Hi! I'm Crafty Clover! Let's discover something amazing. Why do plates move?

The Big Idea

Earth's surface is made of huge slabs of rock called plates. And they're moving right now! They only creep about as fast as your fingernails grow. Underneath, hot rock in the mantle flows very slowly and carries the plates along. Slow heat currents move giant plates! Let's see how.

Step 1

Step one: Earth's inside is hot. Deep inside Earth, it is extremely hot. That heat comes from when Earth formed, and from tiny bits of radioactive rock. That heat keeps trying to escape upward.

Step 2

Step two: hot rock slowly flows. The mantle is solid rock, but it's so hot and squeezed that it flows very slowly, like really thick putty. Hot rock rises, cools, and sinks, again and again, in big loops.

Step 3

Step three: the plates ride along. The plates float on top of the moving mantle. Their own heavy edges also sink and pull, like a tablecloth sliding off a table. They move only a few centimeters each year.

A Closer Look

Let's peek into Earth. The plates are the thin, hard outer layer on top. Below is the hot, slowly flowing mantle. The orange arrows show plates being carried apart or together.

Quick Facts

Quick facts! Plates move about 2 to 10 centimeters a year, about as fast as your fingernails grow. Earth has about 15 major and minor plates, and they fit together like puzzle pieces. Long ago, all the continents were joined together in one big landmass, and scientists think they drifted apart. The Atlantic Ocean is getting a little wider every year.

Think Like a Scientist

Now, think like a scientist! Try this with a grown-up. Warm a pan of water gently, and drop in a little food coloring. Watch the color rise, spread, and sink in loops. How is that like the mantle moving the plates?

Outro

So Earth's plates move because hot rock deep below flows, very slowly. Amazing, right? Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!