Whoa!

Look at all that water.

What is happening over there?

Let's learn more about geysers.

I'm in Iceland at a geyser called Strokkur.

Geysers are places on Earth where hot water erupts from out of the earth.

Some of them are very predictable and some happe unpredictably at random times.

This one erupts every 5 to 10 minutes.

Geysers are pretty rare and are located in areas of geothermal activity.

That's where the ground is hot.

For geysers to form, there has to be heat, water and geological formations that act like plumbing.

The heat comes from magma deep underground, which heats the rocks.

Geysers typically happen where tectonic plates come together and magma is somewhat closer to the Earth's surface.

Water seeps into the ground from rain, snow and glacier melt.

That water then gets heated by the rock.

The rock needs to have a tube.

These tubes are formed in a type of rock called rhyolite.

As the water heats from the magma, it will begin to boil and it will force the water upward.

As that water gets steamy, think of it like a kettle ready to boil.

That steam starts to rise and it will shoot the water above it out of the tube.

Then the water will seep back into the ground and the process starts over again.

If you've ever wondered about hot springs, they are also heated by water, but that water isn't constrained into a tube so it doesn't shoot out into the air.

There are about a thousand geysers in the world and 30 of them are in Iceland.

But that number shifts a little bit as tectonic activity can open and close vents.

Good thing Strokkur is still going strong today.

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