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Mt St Helens Essay Research Paper Mt

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Mt. St. Helens Essay, Research Paper

Mt. St. Helens

Top of Volcano Blown Off In Blast! 18/04/82. 60 people were killed

today when Mt. St Helens blew its top

Mt. St Helens erupted two years ago today in a blast that caused the

volcano to be reduced by 451 metres (1313 feet). The volcano is south-western

Washington and is part of the Cascade Range.

Mt. St Helens had been dormant since 1859 and has let off its first

blast since then today. The volcano killed all life in an area of 180 sq. cm(70

sq. miles) including at least 60 people! The ash and dust spread much farther

than this, of course. Today it is continuing to emit to emit dust and ash at

intervals. Today a monument has been erected called the National Volcano

Monument, in memory of this tragedy.

How A Volcano is Formed

A volcano is formed in this way:

1)Magma starts off below the crust.

2)Magma collects in chamber.

3)Pressure rises.

4)The pressure rises so high that the magma breaks through the crust and

volcano erupts.

Often volcanoes are cone shaped. You might ask: “How do they get like that?”

This is the answer:

When a volcano erupts many minerals and fragments are blown up, many

falling in a circle around the volcano. As lava flows onto this it builds up

around the volcano, so the volcano gets higher still. Each time the volcano

erupts, more lava, minerals and fragments are emitted. Therefore every time a

volcano erupts it erupts it gets taller, and some like Mt. St. Helens have even

become tall enough to be classed a mountain.

NB: This article originally contained pictures, elongating it and making

it better presented.