EARTH'S LAYERS

INNER CORE

• solid iron and nickel
• atoms are so packed together they cannot move
• 1200 km thick

OUTER CORE

• liquid iron, nickel, oxygen, silicon, sulfur
• 2200 km thick
• the movement (convection) of the liquid outer core around the solid inner core is thought to be the source of Earth’s magnetic field

MANTLE

• very hot rocky material
• Upper mantle Asthenosphere - lower layer, plastic-like, pliable Lithosphere – outer layer, rigid, slides on asthenosphere

CRUST

• continents and ocean floor
• 5-70 km thick Two main types of rock in the crust Granite – continents, light colored, less dense Basalt – ocean floor, dark colored, more dense