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Introduction: An Island is Born In my report I will discuss what a volcano is; the anatomy of a volcano, where they can be found, what causes it to erupt and the benefits of a volcano. My chosen volcano is part of the North Atlantic mid-ocean ridge, which caused the newest landmass on earth to appear in 1963. It is now an island called Surtsey. Surtsey has been a site of huge interest to the scientists who have been able to study the colonisation of a virgin landmass by flora and fauna. Whilst volcanic eruptions have caused major disasters and huge loss of life over many years through repeated eruptions, I shall also discuss why people go and live again in the danger zones around these rumbling mountains, and what benefits people also get from volcanic activity and lava flow. What is a Volcano? A volcano is really just an opening in the earth’s surface through which molten rock called magma can escape, often with gas and dust. Usually we only hear on the news or radio about the very powerful eruptions which affect large numbers of people. But at any one time, up to twenty volcanoes may be erupting somewhere in the world. Volcanoes come in different shapes and sizes and there are several types of eruptions. An eruption can be very destructive, killing thousands of people and destroying farmland and settlements. It changes the landscape completely. But an eruption can create new land as well as destroying it. Where are Volcanoes found? Although there are several hundred active volcanoes, they are not distributed evenly around the world. There is a pattern to their location. Most are concentrated around the edges of the 7 continents, as the map shows. Others form chains of islands or long, underwater mountain ranges in the oceans. More than half the world's active volcanoes above sea level circle the Pacific Ocean and are known as the ‘Ring of Fire’. What Causes a Volcano? To understand what causes a volcano, you need to understand how the earth is made up. The earth has onion-like structure but in this case it has four main layers: the crust, the mantle, the outer core and the inner core. The crust is made up of solid rock and varies in thickness. It is more than 60km thick under mountain chains like the Alps and the Himalayas, but just 5km under the oceans. The mantle is a thick layer of molten rock called magma and the core is made up of an outer layer and a solid centre. Temperatures inside the earth are very high – over 5000 degrees centigrade in the core.
Approximate Word count = 1737
Approximate Pages = 6.9
(250 words per page double spaced)
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