Volcanoes

What is a volcano? Volcanoes are mountains, but they aren’t typical mountains. Volcanoes are formed when magma (hot, liquid rock) rises up from beneath and leaks into the Earth’s crust, or surface level. It forms a pool beneath the surface called a magma chamber. As this pool gets bigger, it swells the earth on top of it upwards and outwards.

The term volcano comes from Vulcan, the Roman god of fire and metalworking. It was originally believed that smoke and fire from volcanoes was evidence that Vulcan was doing his metalwork inside of them. A small island was named Vulcano because of its many volcanoes.

Volcanoes erupt when the pressure of the magma beneath the surface becomes too great for the rock above it to contain. At this point, the magma breaks through the surface—sometimes in a great explosion—at which point it is called lava.

The temperature inside a volcano is very hot. Scientists say it can get as hot as 2,120 degrees Fahrenheit. Molten rock turns an orange-yellow color when it reaches 900 degrees. When it cools to 630 degrees, the color becomes dark to bright cherry red.