Inside the Earth Earth has three main layers Crust Mantle Core Based on the compounds that make up each layer The more dense (heavy) the compound the deeper it is found in the Earth

Crust 5 to 100 km thick Thinnest layer of the Earth Two types – Continental and Oceanic Crust Oceanic Crust is more dense than Continental Crust so it sits lower (ocean floor)

Mantle Between Crust and Core 2,900 km thick Mantle is more dense than the crust

Core The center of the Earth Radius of 3,430 km The most dense layer of the Earth

Physical Layers of Earth Lithosphere Made from the crust and the upper part of mantle Divided into pieces called tectonic plates 15 – 300 km thick

Asthenosphere Layer below the Lithosphere Made of solid rock that flows very slowly The Lithosphere moves over the top of this layer 250 km thick

Mesosphere The lowest layer of the Mantle 2,550 km thick

Core Outer Core Inner Core Liquid layer that lies beneath the Mantle Surrounds Inner Core 2,200 km thick Inner Core Solid, dense center of the planet 1,230 km thick