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Describing Volcanoes

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´╗┐Volcanoes A volcano is an opening, in the planet?s surface which allows hot, molten rock, ash and gases to escape from below the surface. The name, ?volcano? originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ?active? volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea. ...read more.


The liquid rocks inside a volcano are called magma and when it flows out it is called as lava. Fresh lava has temperatures from 700 degrees C to 1200?C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world?s largest volcano is the Muano Loa in Hawaii. Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. ...read more.


However not everything associated with the volcanoes is negative. The crust of the earth exists due to the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation. The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes. ...read more.

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