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World Map of Volcanoes
Types of Volcanoes
Can you find the Ring of Fire?
Viscosity
Ø Viscosity is the ability of a fluid to resist flow
Ø Low viscosity (runny) = Magma flows easier
and gas escapes easier. So… lava just “leaks”
out.
Ø High viscosity = magma does not want to
move, or it is “sticky.” Gas is trapped for
longer until eventually…BOOM, big volcano
http://www.youtube.com/watch?
v=xExdEXOaA9A
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Shield Volcano
Mt. Kilauea (Hawaii)
Ø Very Long
Ø Gentle slopes
Ø Basalt rock
(oceanic)
Ø Non-explosive
(Lava oozes out
or spurts)
Ø LOW Viscosity
Composite Volcano (Stratovolcano)
Composite Volcano (Stratovolcano)
Ø  Circular bottom
Ø  Steep Sides
Ø  Explosive,
fragments plus lava.
Ø  More unpredictable
Ø  (Continental Rock)
Ø  HIGH Viscosity
Composite Volcano (Stratovolcano)
Mt. Saint
Helens,
Washington
Mt. Saint
Helens,
Washington.
Before and
After
Eruption
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Cinder Cone Volcano
Ø  Smallest of the 3
Ø  Very Steep
Ø  Ejected material
returns.
Ø  Common on
edges of other
volcanoes
Mt. Parícutin, Mexico
Examples of Types of Volcanoes
Examples of Types of Volcanoes
Types of
Volcanoes
Shield
Volcano
Composite
Volcano
(Stratovolcano)
Cinder Cone
Volcano
Kilauea,
Hawaii
Mt. St.
Helens,
Washington
Parícutin,
Mexico
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Effects of Volcanoes
Examples of Types of Volcanoes
Cinder Cone
q Pyroclastic Flow
q Ash
q Lahar
q Toxic Gas
q Climate
Shield
Composite /
Stratovolcano
Hot Spot Volcanoes
Hawaii
q Hot Spot Volcanoes develop in the middle
of plates, unlike most volcanoes that
develop at plate boundaries
q A mantle plume brings heat to the
lithosphere where the volcano develops.
q As the oceanic plate moves from sea floor
spreading, the hot spot volcano also
moves
q EXAMPLES: Hawaii, and Yellowstone
Yellowstone Super Volcano!
Yellowstone Super Volcano!
q Yellowstone National Park currently sits
over a giant hot spot in the middle of a
continental plate.
q When it erupts, it will be HUGE MEGA
VERY BIIIIIIIG
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Yellowstone Super Volcano!
q So…. When will it erupt?
q Scientists think soon, how soon?
Geologically soon could mean on the order
of the next couple hundred thousand years…
What are some major cities
that are close to Volcanoes?
Mexico City
Mt Etna, Italy
Kagoshima – Sakurajima, Japan
Galeras, Columbia
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Mt Rainier, Seattle, Washington
Mt. Vesuvius, Italy
Mt. Vesuvius, Italy
79 AD - Pompeii
Volcanoes can have GLOBAL effects
In Review…
q Ring of Fire
q Viscosity
q Shield Volcano
q Composite Volcano
q Cinder Cone
q Hot Spot
Video
•  https://www.youtube.com/watch?
v=VuQrUwFn6bU
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