Inside the Earth

The Layers Within

Composition (What it is made of)

• Crust

• Mantle

• Core

• The Earth is divided into three layers based upon the material it contains.

The Crust

• Outer layer• 5-100 km thick• Made of light minerals

such as silicon and aluminum

• 2 types of crust– Oceanic (very dense,

made of basalt)

– Continental (less dense, made of granite)

Oceanic and Continental Crust

• Oceanic Crust is thin but very dense.

The Mantle

• Middle layer• Very thick layer• Contains some

aluminum and silicon but also has heavier minerals such as magnesium.

• Where lava comes from

The Core

• Made mostly of iron, very heavy mineral

• 1/3 of the earth’s mass

• Very hot

• Inner core is solid

• Outer core is liquid

Earth’s Layers

• How are the earth’s layers similar to an egg?

• Shell=crust• Egg white=mantle• Yolk=core

A new way to divide the Earth.

• The Earth is also divided up into layers based upon the physical properties of

each layer.

• Lithosphere

• Asthenosphere

• Mesosphere

• Outer Core

• Inner Core

Physical Structure of the Earth(5 Layers)

• Lithosphere- rigid outer layer (crust and part of the mantle)

• Asthenosphere- solid rock that flows slowly, found below lithosphere (like frosting) part of the mantle

• Mesosphere- middle layer, part of the mantle. very rigid magma

• Outer Core- liquid layer

• Inner Core- solid, very dense

How the 2 layers line up

The Layers Combined

Tectonic Plates• Earth’s crust is broken into about 19

pieces

• These plates move on top of the asthenosphere