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