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Volcanoes
are
Hot Stuff!
Created & Adapted by: Dawn Easley
VOLCANOES
EQ: What are the types of
volcanoes and how are they
formed?
So, What Is a
Volcano?
•A volcano is a weak spot in the
crust where molten material, or
magma, comes to the surface.
Where are the Volcanoes?
The Ring of Fire
Subduction zones
The Ring of
Fire is a
volcano
belt
formed by
many
volcanoes
that
border the
Pacific
Ocean.
The Ring of Fire
**Click on picture for video.
How are
volcanoes
formed?
Deep in the earth it is very
hot and rocks melt.
The melted rock is
called magma and is
lighter than the rocks
around it so it rises.
Sometimes it finds a
crack or hole in the
earth’s crust and bursts
through it (vent). This
is how a volcano begins.
Why do
volcanoes
erupt?
Pressure builds deep in the
earth where the magma is.
Suddenly the gases escape and
violently explode.
It’s a Volcano!
Look up, there’s a fire burning!
Way up, in a mountain high.
Look up, when there’s steam,
smoke, or ashes.
When the crater starts to blow.
And the lava starts to flow.
Then you will surely know.
It’s a volcano! It’s a volcano!
Nature’s always changing
everything we see.
Always rearranging under the
land and in the sea.
It’s a volcano! It’s a volcano!
Three kinds of volcanoes can happen
Composite, Shield, or Cinder Cone.
But when the earth starts shaking
Look down, in the earth’s deep zone
And the lava starts to flow.
Way down, under the soil & rock.
You’ll find that there’s magma burning. It doesn’t matter which one blows.
For then you will surely know.
Pushing up through the plates
It’s a volcano! It’s a volcano!
in the rock crust.
Trying to start a fireworks show.
And when the lava starts to flow.
It’s a volcano! It’s a volcano!
What are the
different
kinds of
volcanoes?
Classifying Volcanoes
• Composite or
Strato
• Active
• Cinder
Cone
• Intermittent
• Shield
• Dormant
• Extinct
VOLCANIC ACTIVITY
ACTIVE - A volcano that has erupted in the
recent past and is expected to erupt again.
INTERMITTENT – A volcano that erupts in
fairly regular time periods.
DORMANT - A “sleeping” volcano. A volcano
that has not erupted in the recent past, but could
erupt again.
EXTINCT - A volcano that is not expected to
erupt again.
Shield
Volcanoes
Volcanoes that build up from
many slow, steady, flows of hot
lava are called shield volcanoes.
This kind of volcano is low and
broad with gently sloping sides.
They look like a warrior’s shield.
Shield Volcanoes
• A shield volcano is a
large, gently sloped
volcano made up from
many slow, steady flows
of hot lava. Low and
broad – like a warrior’s
shield.
• Materials Erupted:
mainly liquid lava, so the
volcano is made of layers
of hardened lava.
– Non-explosive eruptions
• Example: the volcanoes
of Hawaii
**Click picture for video.
Cinder Cone
Volcanoes
Cinder cone volcanoes form
when solid rock and ash shoot
up into the air and fall back
around the volcano opening.
The cinder cone volcano has
steeply sloped sides.
Cinder Cone Volcanoes
• A cinder cone volcano is a
relatively small, volcano with
steep sides. It is where rock
and ash shoot up into the air
and fall back around the
opening.
• Materials Erupted: small
pieces of hardened lava
(rock fragments) - called
cinders
– Moderately explosive
• Example: Paricutin (Mexico)
**Click picture for video.
Composite
or
Stratovolcanoes
Stratovolcanoes, also called
composite volcanoes, erupt with
molten lava, solid rock, and ash.
The layers pile up much like
layers of cake and frosting. The
layers form into symmetrical
cones, and the slopes are steep.
Composite Volcanoes
• A composite volcano is
a huge mountain-like
volcano. Layers build
up like frosting on a
cake forming a cone
with steep sides.
• Materials Erupted:
sometimes lava,
sometimes rock
fragments.
– May have very
explosive eruptions
• Example: Mount St.
Helens
**Click picture for video.
Volcano Research
You will be assigned a volcano to research. Each volcano
has something interesting and unique about it - find out
what it is!
For each volcano you will be researching
*Where is the volcano located ?
*When did the famous eruption occurred?
*What type of volcano it is?
*What is unique or interesting about the volcano?
*Is the volcano active, dormant or extinct?
**Some helpful websites are listed on the next slide . . .
Try these sites to get your
research started:
Volcano World
Hawaii Volcanoes
Smithsonian Volcano Page
Volcanoes Live
Info. on Mount St. Helens
Encyclopedia.com (type in
volcano name)
Info. on Mount Rainier
Volcanoes Listed by Name
Encarta (type in volcano name)
U.S. Geological Survey - volcano page
Pictures, Images, and information From:
Soames Summerhays/Photo Researchers, Inc.
Kraft-Explorer/Photo Researchers Inc.
Masao Hayashi-Dung/Photo Researchers Inc.
Why Do Volcanoes Blow Their Tops? By Melvin and
Gilda Berger
www.usgs.gov/education/learnweb/volcano/index.htm
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