Analyse the Factors That Cause Differences in the Hazards Posed by Volcanoes Around the World

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Analyse the factors that cause differences in the hazards posed by volcanoes around the world A hazard is a situation that poses a level of threat to life, health, property or environment. The level of hazard posed by different volcanoes can vary greatly, from a weak eruption with minimal impact that causes little damage, to a violent and life threatening explosion. The difference in hazard that a volcano poses is determined by a series of different factors. Those combination and individual factors that determine the difference in hazard by a volcano will be explained within this essay. The first factor to be considered is the type of the magma. With acidic magma, the magma is very viscous and this can determine how powerful and explosive an eruption is. This is due to the high silica content and low temperature. The more silica in the magma, the thicker and stickier it is. This type of magma is dangerous because it has a tendency to plug the volcano, trapping gasses which build pressure and eventually erupting violently! This is evidenced in subduction volcano's like Mt. St. Helens and Krakatoa are common types of these volcano's. The magma plugs the volcano which creates and increase in pressure and latent heat which eventually creates a huge explosion. They release enormous amounts of energy and create eruption columns of gas and ash that can rise up to 50 km (35 miles) high at speeds of hundreds of meters per second. Ash from an eruption column can drift or be blown hundreds or thousands of miles away from the volcano. Creating such hazard as occurred at Mount St. Helens in 1980. which produced falls of ash, scoria and lava bombs miles from the volcano, and pyroclastic density currents that razed forests, striped soil from the bedrock and obliterated anything in its paths. These type of eruptions are known as Plinian and are hard to predict as they are
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