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World Map of Volcanoes

Can you find the Ring of Fire?

Types of Volcanoes

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 Ø Very Long Ø Gentle slopes Ø Basalt rock

(oceanic) Ø Non-explosive

(Lava oozes out or spurts)

Ø LOW Viscosity

Mt. Kilauea (Hawaii)

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)

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

Types of Volcanoes

Shield Volcano

Kilauea, Hawaii

Composite Volcano

(Stratovolcano)

Mt. St. Helens,

Washington

Cinder Cone Volcano

Parícutin, Mexico

Examples of Types of Volcanoes

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Examples of Types of Volcanoes

Cinder Cone

Shield

Composite / Stratovolcano

Effects of Volcanoes

q Pyroclastic Flow q Ash q Lahar q Toxic Gas q Climate

Hot Spot Volcanoes 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

Hawaii

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

Yellowstone Super Volcano!

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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