http://www.everythingselectric.com/wp-content/uploads/electric-Volcano-and-magma-evidence.jpg

 

Magma

Volcanoes begin deep within the mantle where magma forms. Magma close to the surface melts and flows easily because the pressure is less. Magma can gush out of weak spots in the crust. A volcano is an opening in the earth where hot material erupts.