Earth's Interior

Crust

The outermost layer of the Earth.

Continental Crust

Thicker part of the crust made of granite, which is less dense.

Oceanic Crust

Thinner part of the crust made of basalt, which is denser.

Mantle

The thickest layer of the Earth, made of hot silicate rocks.

Core

The center layer of the Earth, composed mainly of iron and nickel.

Lithosphere

The rigid and brittle layer that includes the crust and the top of the mantle.

Asthenosphere

Upper mantle layer that is plastic/semi-liquid and flows slowly.

Outer Core

The only liquid layer of the Earth, responsible for creating the magnetic field.

Inner Core

The very center of the Earth, a solid metal due to extreme pressure.

P-Waves

Primary seismic waves that are fastest, move like an accordion, and can travel through solids and liquids.

S-waves

• Slower (they arrive second).

• Move like a snake (Side-to-Side/Shear).

• Can ONLY travel through solids. (They stop at the liquid outer core).