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It's started. The end of the world has started. On Sunday, at
exactly 19.58, the Yellowstone Supervolcano showed signs of an imminent eruption.
Supervolcanoes are much larger than average volcanoes. They emit at least 1,000km3 of material and
could cause a cataclysmic eruption, one so dangerous that the whole world would be affected.
The convection currents in the mantle force magma through a fault in the crust. Unlike normal
volcanoes, in supervolcanoes magma rises to form a giant reservoir under the Earth's crust as
there is no crack for the magma to escape through to the surface. As the great pressure builds,
a large swelling starts to appear on the surface.
When the pressure is too great, cracks start to appear on the surface and gas and ash erupt
from the reservoir of magma.
As the pressure is released, the magma chamber shrinks and the swelling collapses causing a
depression called a caldera, usually surrounded with high walls, which is so immense that it is
only clearly visible from the space. This also suggests that a major eruption happened in the past.
Unlike regular volcanoes, supervolcanoes are not
found in patterns or near plate boundaries but
they usually form due to hot spots. This is where
the crust is weakened by plumes of magma.
There are seven known supervolcanoes in the world including three in the USA (Yellowstone in
Wyoming, Long Valley in eastern California, and Valley Grande in New Mexico), Taupo in New
Zealand, Aira in Japan, Toba in Sumatra and the Siberian Traps in Russia.
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The last supervolcanic eruption happened 74,000 years ago when Toba erupted. The volcano released
3,000km3 of magma and ash. It was thought that world temperatures fell between 3 and 5°C as the toxic
gases blocked the Sun. Scientists speculate that the world went into a 610 year volcanic winter after the
eruption resulting in the human population reducing in number to between 1,000 and 10,000 bringing
mankind to the brink of extinction.…read more
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Scientists have predicted catastrophic events for the world if Yellowstone erupts. Volcanic ash will rise
4050 km into the atmosphere and maybe even block the Sun causing the world temperature to decrease
drastically by about
12°C causing a volcanic yearround winter for two to three years like the one that happened after the
Toba eruption. Extra rainfall due to extra particles in the atmosphere could cause mudflows and landslides
which could kill about
50,000 people.…read more