3 Types of Heat transfer

• Radiation- transfer of heat through empty space

• Conduction- transfer of heat by direct contact

• Convection- transfer of heat involving the movement of fluids-liquids and gases

Asthenosphere

• Heat from Earth’s core and mantle cause hot columns of mantle material to rise

• Hot material spreads and forces the cooler material to sink 

Convection in the mantle begins when rock near the core is heated. This causes the rock to rise towards the surface of the earth. When it reaches the lithosphere it (usually) spreads out and begins to cool.

As it cools, it begins to sink back towards the core, and the process starts over again.