The Earth is made up of layers. If the planet could be cut in half, the layers would look sort of like the inside of an onion.

The planet has a solid center that is very hot. This is called the inner core. The next layer is the outer core, which is liquid. The core is surrounded by a layer of melted rock. The melted rock moves like liquid.

This middle layer is called the mantle. The upper part of the mantle becomes solid. The outermost layer, called the crust, is solid, too. Together, these solid parts are called the lithosphere.

Earth's crust is made up of hard rocks. It is the only part of the Earth that humans see.

There are two types of lithosphere. One is on land. The other makes up the ocean floor.

Moving, Sliding Plates

The lithosphere is divided into large chunks. These are called tectonic plates. These plates slowly "float" on top of melted rock beneath them.

Earthquakes happen when plates slide past each other. Deep trenches are created where plates tear apart. Mountains form where plates come together. Scientists study these processes or movements. They are part of what scientists call plate tectonics.

The Lithosphere And Climates

The lithosphere is affected by things like water, ice and air. Together, these create different climates. Wind wears down rocks into sandy deserts. On tall mountains, cold air and snow create icy slopes. Healthy soil and rain make it easy for living things to grow in the forest.

These environments are all very different. Plants and animals live in all of them. They have adapted. This means they have changed over many, many years. The changes help them to survive in their environments.

Lithospheres On Other Planets

Some other planets also have lithospheres. Mercury, Venus and Mars all have a lithosphere. Their lithospheres are thicker than Earth's lithosphere.