Earth’s Crust Facts For Kids (Fun Facts + Diagram)

Earth’s crust is the outermost layer of the Earth. This rocky layer is what we live on, the ground below us! Earth is divided into three layers: the crust, the mantle, and the core.

Jump to: Where is the Crust | Continental Crust | Lithosphere & Tectonic Plates | 10 Facts

4 Interesting Facts About The Earth’s Crust

1. Earth’s crust is the outer layer of the Earth
2. The crust has 2 layers: Oceanic Crust (under oceans) and Continental Crust (under the continents)
3. The crust is very thin compared to the rest of the Earth, about 1% of Earth’s mass.
4. Earth’s crust has tectonic plates, and they move as fast as fingernails grow!

Read on to learn everything you need to know about Earth’s crust. You can also try our fun activity which teaches you how to make a model of the Earth’s layers!

Where is Earth’s Crust?

The crust is the Earth’s outermost layer, meaning it’s the layer closest to the surface. We live on top of Earth’s crust, and it stretches under both the land and the oceans.

How Thick is Earth’s Crust?

Earth’s crust thickness depends on which of the two layers you are on.

• Oceanic Crust (under oceans): about 5 miles
• Continental Crust (under continents): 20-40 miles.

The crust is like skin, it is very thin compared to the rest of the Earth, but it is very important.

Continental Crust vs. Oceanic Crust (Simple Comparison)

What Exactly is Earth’s Crust Made Of?

Unlike a pizza crust, Earth’s crust is not soft or flexible. In fact, it’s extremely hard, because it’s made up of different rocks and minerals.

Continental Crust

Continental crust is the crust under the land (aka the continents), and it’s made mostly from a rock called granite. It’s also made up of igneous, sedimentary, and metamorphic rocks.

• Igneous rocks are formed by cooled magma
• Sedimentary rocks are formed by layers over time
• Metamorphic rock is formed by high heat and pressure

Oceanic Crust

Under the ocean is oceanic crust, which is made mostly from a rock called basalt. It is also made up of iron, oxygen, silicon, magnesium, and aluminum.

The Main Elements in Earth’s Crust

The crust is made up of eight different chemical elements, with oxygen being the most abundant (46%). All these “elite eight” elements that make up crust are:

• Oxygen
• Silicon
• Aluminum
• Iron
• Calcium
• Sodium
• Potassium
• Magnesium

While continental crust is thick and light-colored, oceanic crust is thin and very dark. Oceanic crust is only about 3-5 miles thick, but continental crust is around 25 miles thick.

25 miles may sound very thick, but the crust is actually the thinnest of Earth’s three layers, making up only 1% of Earth’s volume.

The Lithosphere and Tectonic Plates

To have a really good understanding of Earth’s crust and its importance to our planet, you need to know that it is part of the lithosphere.

The word “lithosphere” refers to the crust and the top part of the mantle, which is the layer right underneath the crust.

The lithosphere is divided into pieces called tectonic plates. You can think of tectonic plates as giant rocks that “float” across the lower part of the mantle.

Sometimes these plates move apart and sometimes they bump into each other. Sometimes one plate may slide under another plate.

There are about a dozen large crustal plates and many smaller ones on the planet, and they all move at different speeds, the fastest as fast as fingernails grow!

Even though a few inches of movement in a whole year doesn’t sound like very much, the movement of the plates is a big deal!

That’s because the moving plates create all kinds of natural disasters like tsunamis, earthquakes, and volcanoes. Plate movements even help build mountains.

10 Fun Facts About Earth’s Crust

1. Earth’s crust is the outer layer of Earth that we live on
2. The crust is only about 1% of Earth’s mass
3. Oceanic crust is under oceans
4. Continental crust is under continents
5. The boundary between the mantle and the crust is called the Moho
6. The Moho can be over 752°F
7. The Crust and the Mantle make up the Lithosphere
8. Scientists measure crust movement with satellites and GPS
9. Scientists in Russia dug a 7.5 meter hole into the crust, the deepest hole ever dug.
10. The crust is mostly made of Oxygen.

¿Qué es la corteza terrestre?

La corteza terrestre es la capa más externa de la Tierra. Es una capa de rocas y minerales donde vivimos.

Other about the Earth’s crust

Even though the Earth’s crust can get as hot as 752 degrees Fahrenheit (400 degrees Celsius) at its deepest points, it is still the coldest of Earth’s layers.

Most of the time, Earth’s crust is the same temperature as the surface of the Earth.

The deepest part of the crust is underneath mountains, where it can be up to 43 miles thick.

Were you wondering how scientists measure the movement of the tectonic plates? Scientists use satellites and GPS to measure plate motion.

In Russia, scientists drilled 7.5 miles into Earth’s crust. Wow! The crust is the only layer that is shallow enough to be studied by drilling.

Next time you hear the word “crust,” you can think of more than just pizza or pie.

Now you also know about the crust you walk on every day—Earth’s crust—and the role it plays in volcanoes, tsunamis, the creation of mountains, and more!

Earth Science

Andrew Owner and Editor in Chief

Andrew is the Owner and Editor in Chief of CoolKidFacts.com, A Chemical Engineering grad from the University of Texas at Austin, Andrew uses his experience of taking complicated topics and translating them into kid friendly and fact checked explainers in everyday language.

See Full Bio