Mt St Helens was once a symmetrical cone, until May 18th 1980 when it violently erupted. The eruption removed the upper part of the summit destroying 396m of it, the volcano was left with a horseshoe-shaped crater. The eruption was caused by a magnitude 5.1 earthquake that began at 8:32am, 15 seconds later the eruption occurred. In 15 seconds the whole north face mountain collapsed, letting out superheated gases and trapped magma in a colossal explosion. The sudden release of pressure of the magma creates a “news ardentes”, the cloud of gas and debris were spilling out of the volcano at almost supersonic speeds. Not long after this shock blast, another explosion occurs, making a mushroom-shape like cloud of more ash and gasses. Eruptions continued for another nine hours, an estimated 540 million tons of ash was said to have drifted. The gloomy dark ash covered the skies not only in the cascade ranges regions but it also drifted 5,700km covering over seven other states.
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AftermathThe aftermath of the eruption was catastrophic. The heat vaporized glacial ice and snow around the volcano in a heartbeat causing humongous mudflows moving through the river systems west and south east of Mt St Helens. Not only did the eruption cause mud flows but it also caused Cowlitz River to flood losing 85% of its water capacity, this was caused by the mud flows. Many other creeks, and rivers lost a high capacity of water, in total 13, 761,987 litres of water was lost (from the rivers and creeks). The treacherous hot mud moved at 145kph, swallowing anything in its path. Vegetation was perished as were trees equalling to 9,438,948 litres of timber were damaged and destroyed. A huge amount of environmental loss was caused but lives were also lost in this devastating event. A total of 57 lives were taken away and 200 homes were gone. Still to this the 1980 eruption caused the most damage in American History.
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AftermathEconomically, Mt St Helens eruptions $1.1 billion worth of damage, plus the Congress approved $950 million in emergency funds that covered Army Corps of Engineers, FEMA (Federal Emergence Management Agency) to help with the recovery endeavour. More than 297.73km roads and 24.14km of railways were also completely damaged. An extensive amount of ash clogged sewage systems and what was left of the damaged cars and buildings. Although this was a treacherous day, Americans and people across the globe joined together in repairing the damage. Now, the land is still healing, though it still carries its natural beauty, with the landscape being altered permanently it is a constant reminder of what happened on May 18th 1980.
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The Scientist' roleIt is impossible to stop volcanoes from erupting, although we can reduce the damage by detecting if the volcano will erupt. Volcanologist (people who study volcanoes) monitor the volcanoes to see if there are any warning signs. Some of the warning signs include small earthquakes beneath or near the volcano, minor inflation or swelling and an increase of the heat and gas coming from the vents of the volcano. These signs can be evident weeks or even months before the eruption even occurs. Volcanologist can monitor the signs from field observations, measuring temperature of acidity (pH), studying the ground cracking patterns, taking samples of gas, chemical sensors to measure sulphur, thermal imaging, satellite cameras and seismometers to detect earthquakes that could cause the volcano to erupt. Mt St Helens in particular gets monitored very closely as it has been active in the past few years.
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