What are volcanoes and earthquakes?

What are Volcanoes and Earthquakes?

Volcanoes begin deep within the mantle  where magma  forms. Magma is hot, pasty, rock that moves within the mantle.

Magma  has a lot of pressure inside of it since it contains a lot of gas. When the pressure builds up the magma  can gush out of weak spots in the crust . A volcano is an opening out of where the weak spots in the crust  erupt. 

An eruption is like opening a can of shaken soda. Bubbles of gas separate from the liquid and force the liquid out. Material that erupts from a volcano contains ash , cinders , and hot, molten  rock called lava. As lava cools and hardens, it becomes igenous rock . Igenous rock is brand new crust. If the rock builds to great heights, a new mountain or island can form.