EARTH´S LAYERSMr. Jaime Peña

Planet Earth…2012

Earth is our planet, our home. Have you ever wonder what lies beneath

your feet? Well, let´s take a fantastic look at it!

Compositional LayersTo study the layers of Earth, scientists make 2 classifications of them. Compositional and Physical Layers. They are related to each other.

In this picture we can see the Compositional layers. They include: The Crust, the Mantle, and the Core.

Compositional LayersCrust: It is the layer we live on. It includes all the continents and even the ocean floor! The crust is made up of 3 elements: oxygen, silicate and aluminum.

Mantle: It is the middle of Earth´s compositional layers. Some of the rock in the mantle is like wax that is soft but not completely melted.

Core: Innermost part of Earth. Made up mostly of 2 elements: iron and nickel which are metals.

Physical Layers

There are 5 Physical Layers. They are determined by their physical properties, such as if a layer is hard or soft, solid or liquid.

The Lithosphere is the uppermost layer of Earth. It is almost all solid. It is directly related to the Crust and a little part of the Mantle. It is divided into pieces called Tectonic Plates.

Physical Layers

Next come the Asthenosphere and the Mesosphere. Both are related to the Mantle. The tectonic plates float on the Asthenosphere, which is soft. Rock in the Mesosphere is softer than rock in the Asthenosphere.

Physical LayersThe innermost physical layers are the Outer Core and the Inner Core. In this picture, they are represented by the red and the yellow part. Both are related to the Core. They are divided because the Outer Core is liquid and the Inner Core is solid. They are made mostly of iron and nickel.

The reason why the Inner Core is a solid ball of iron is because of the pressure of all the other layers over it. But that doesnt mean is cold. Some scientist compare its heat to the temperature at the Sun´s surface!

Compositional and Physical Layers

Compositional Layers

Physical Layers

Crust

Mantle

Core

Lithosphere

Asthenosphere

Mesosphere

Outer CoreInner Core