volcanoes

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volcanoes
BY ALISTAIR RHODES
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Explosive Volcanoes Sometimes volcanoes explode
violently.Volcanoes that are viscous lava are
most likely to do this. The thick, sticky lava
traps gas under it and shuts the volcanoe's vent.
When pressure increases, a voilent explosion
blows out the lava. Pieces of rock and a loads of
ash are hurled high into the air. Clouds of ash
flow like hot avalanches down the sides of the
volcano.
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INTRODUCTION
My Project is going to be about Mount Etna. Mount
Etna is situated on the island of Sicily. Mt Etna
is the most active volcano in Europe and one of
the oldest volcanoes in the world. Mt Etna is
over 3333metres high!
Mt Etna is very big and this is picture from
space. As you can see Etna is over 20 km in
diameter . Etna is near the city of Catania. The
surface of Etna is covered in Historic lava from
past eruptions. Etna has the longest record for
historic eruptions. The first was in 1500 B.C.
Since then Etna has erupted 190 times. When Etna
erupts it usually is a gentle Eruption large
eruptions are rare.
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One of the most dramatic eruptions of Etna was in
1669. Earthquakes began on February 25 and caused
great damage in Nicolosi, about 6 miles (10 km)
South and East of Catania. The eruption began on
March 11 as a 7 mile (12 km) fissure opened from
near Nicolosi to Mt. Frumento Supino, 1 mile (2
km) from the summit. Several more vents formed.
On April 12 flows arrived at the walls of
Catania. Lava rose to the top of the wall and
cascaded over. Lava also knocked over a section
of was 120 feet (40 m) long. Large parts of the
town were destroyed. Lava reached the sea on
April 23. The eruption stopped on July 15
This is a map of the major volcanoes in Italy.
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The structure of the Earth
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THE STRUCTURE OF
THE EARTH The Earth is split into four sections.
These are the core, the outer core, mantle and
crust. The crust is the thinnest part of the
Earths structure but it is still pretty thick as
it is between 35km and 70km thick. The thickest
part of the Earth is the mantle it is 2,900km
thick. The core is 5,000 degrees celcius.
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This is a basic structure of a volcano
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A more detailed
structure of the Earth
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PRYOCLASTIC FLOWS
Pyroclastic flows area mixture of hot, dry rock
fragments and hot gases that move away from the
vent that erupted them at high speeds. They may
result from the explosive eruption of molten or
solid rock fragments, or both. They may also
result from the eruption of lava when parts of
dome or a thick lava flow collapses down a steep
slope. Most pyroclastic flows consist of two
parts a flow of coarse fragments that moves
along the ground, and a thick cloud of ash that
rises above the basal flow. Ash may fall from
this cloud over a wide area downwind from the
pyroclastic flow.
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EARTHQUAKES
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This is a map that shows the plate boundaries.
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Earthquakes occur because the Earths plates
move either away from each other or closer to
each other causing the ground to shake and crack
and this can cause bridges to collapse and
buildings to collapse. The Earthquake itself
doesnt kill anyone the damage and destruction
kills people.
This picture shows the destruction of earthquakes
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THIS WAS DONE BY............
BY ALISTAIR RHODES