THE EARTH

CRUST 0-200KM DEEP

The surface of the Earth is made of rigid yet flexible tectonic plates. Continental plates are old and light, composed of low-density minerals rich in silica. Continental plates average 15 to 30 kilometres thick, although the most ancient plates can be up to 200 kilometres thick. Oceanic plates are younger and denser, composed of high-density minerals rich in iron and magnesium with little silica. At just

7 to 10 kilometres thick, they are thinner than continental plates.

MANTLE 30-2,890KM DEEP

The thickest layer of the Earth consists of hot, ductile rock rich in iron and magnesium. Over millions of years, the mantle flows in enormous convection cells (shown here by yellow arrows) that drive plate tectonics and feed hot spots below volcanoes. Diamonds form in the upper mantle at depths of 150 to 800 kilometres.

CORE 2,890-6,371KM DEEP

The Earth’s iron-nickel core is a solid inner ball wrapped in a liquid outer core that is constantly in motion. This hot, fluid metal generates the planet’s protective magnetic field, which deflects the Sun’s harmful solar wind.