A volcano is a Earth's surface that is formed by molten rock forced from the mantle. Volcanoes form when hot material,called magma,rises and leaks into the crust. The magma rising from the lower ground gathers in a reservoir,forming the magma chamber. As the pressure builds up,the volcano gets bigger. A volcano usually swells before its eruption.
Volcanoes often occur at the plate boundaries because that's where Earth's shifting plates meet or split apart. More than half of the volcanoes are in the Ring of Fire.The Ring of Fire surrounds the Pacific plate between the West coast of North America and the East coast of Asia. The volcanoes in Indonesia are the most active compared with all the other volcanoes.
Volcanoes have claimed many lives during the past years. Most people die because of the poisonous gas ,not the lava. The gas is located within the magma. The type of gases in magma are water vapor,sulfur dioxide,and carbon dioxide. This combination can suffocate a human in less than 2 minutes.
What's interesting is that lightning can occur from the volcano into the sky.Nobody knows why,but scientists believe all the particles of ash in the clouds move around and bumping into each other, producing strong static charges.So its best not to get near a volcanoe during eruption.
