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VOLCANOES
By: M.Wells
Facts About Volcanoes
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Volcanoes are mountains that build higher and
higher as they erupt.
Once a volcano erupts it might produce ash or lava.
Volcanoes can make many types of rocks.
There are as many 1,500 active volcanoes around
the world.
The most important volcano in the United States is
Mt. Ranier.
Components of a Volcano
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Parts of a Volcano
Images of Volcanic Rocks
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Scoria
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Basalt
Volcanoes
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Effects on People
Volcanoes affect people in many
ways, some are good and some are
not. Some of the bad ways are that
houses, buildings, roads and fields
can get covered with ash. As long
as you can get the ash off
(especially if it is wet), your house
may not collapse, but often people
leave because of the ash and are
not around to continually clean off
their roofs. If the ash fall is really
heavy it can make it impossible to
breathe.
The Good Parts
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The main good effect that
volcanoes have on the environment
is to provide nutrients to the
surrounding soil. Volcanic ash often
contains minerals that are
beneficial to plants, and if it is
very fine ash it is able to break
down quickly and get mixed into the
soil.
Volcanoes
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Effects On the Environment
Volcanoes are notorious for their
devastating effects, not only on
human life but also on the global
environment. Lava, emission of
toxic gases, ash fall, lahars and
landslides are some of the most
dangerous hazards of volcanic
eruptions.
Lava flows are usually slow and
therefore, people can easily escape
them. However, they can cause
extensive economic loss by burning
and burying buildings and crops.
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Volcanic eruptions are generally
accompanied by dreadful vibrations
in the surrounding areas, which
causes landslides. In the past, such
landslides were responsible for
burying surrounding cities.
A volcanic eruption is a natural
calamity, that besides wrecking
havoc on human life and property,
can cause a lot of environmental
changes by contributing to acid
rain and global warming
Volcanoes- Key Terms/Definitions
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Magma – molten material
beneath or within the earth’s
crust, from which igneous rock
is formed.
Lava – the molten, fluid rock
that issues from a volcano or
volcanic event.
Ash – the powdery residue of
matter that remains after
burning.
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Eruption Cloud – a convoluted
rolling mass of water vapour
and ash that is highly charged
with electricity and overhangs
a volcano during eruption.