A volcano is a special kind of mountain that actually builds itself! It is made of red-hot rock that pushed up out of a crack in the earth.
A volcano begins deep inside the earth when the force of hot gas pushes melted rock up. With a loud, deep rumble, the ground begins to shake and burst open. Fiery hot rock can shoot into the air, and melted rock may flow out of the earth. With the volcano, there may be earthquakes and explosions. Huge clouds of smoke and ash may fill the air.
The melted rock is called magma. Magma that pours out onto the earth’s surface is called lava. Some lava is as thick as syrup, and some is as thin as soup.
As thin lava stops flowing and cools, it hardens into smooth sheets of rock. Thicker lava cools into rough, jagged sheets.
As more lava pours out of the earth, it falls on the cooled rock. As the ash and rock pile up, a new mountain forms. It forms a cone-shaped mountain with a deep tunnel down its middle.
Picture Credit : Google