Melting
It's getting very hot down here!
Oh no - I'm melting, I'm melting...
It can get quite hot deep in the Earth's crust. In fact, it can get so hot that the rocks that make up the crust can actually begin to melt.
This molten material is called magma. It is less dense than the surrounding rock so it tends to move upwards through the crust.
Magma also comes from material below the Earth's crust - the mantle. This new material rises up from the mantle and adds to the magma produced from the molten crust.
