Volcanoes!!!

By: Jamie Stephenson

What is a Volcano?

• A volcano is a landform (usually a mountain) where liquid rock erupts through the surface of the planet.

• In simple terms a volcano is a mountain that opens downward to a pool of molten rock (magma) below the surface of the earth. It is a hole in the Earth from which molten rock and gas erupt.

The name "volcano" gets its origin from the name of Vulcan, a god of fire in Roman mythology.

Did You Know -

What causes volcanoes to erupt?

• The Earth's crust is made up of huge slabs called plates, which fit together like a jigsaw puzzle. These plates sometimes move.

• Between the Earth's crust and the mantle is a substance called magna which is made of rock and gases.

• When two plates collide, one section slides on top of the other, the one beneath is pushed down.  Magma is squeezed up between two plates.

In Other Words -

• Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth.

What is the difference between lava and Magma?

• Magma is liquid rock inside a volcano.

• Lava is liquid rock (magma) that

flows out of a volcano. Fresh lava ranges from 1,300° to 2,200° F (700° to 1,200° C) in temperature and glows red hot to white hot as it flows.

The different parts of a Volcano

• Magna - Molten rock beneath Earth's surface.

• Parasitic Cone - A small cone-shaped volcano formed by an accumulation of volcanic debris.

• Sill - A flat piece of rock formed when magma hardens in a crack in a volcano.

• Vent - An opening in Earth's surface through which volcanic materials escape.

• Flank - The side of a volcano. • Lava - Molten rock that erupts from a

volcano that solidifies as it cools.• Crater - Mouth of a volcano - surrounds

a volcanic vent.• Conduit - An underground passage

magma travels through.• Summit - Highest point; apex • Throat - Entrance of a volcano. The part

of the conduit that ejects lava and volcanic ash.

• Ash - Fragments of lava or rock smaller than 2 millimeters in size that are blasted into the air by volcanic explosions.

• Ash Cloud - A cloud of ash formed by volcanic explosions.

The 3 Different Types of Volcanoes

• There are 3 different types of volcanos:

• Active - eruptions can be anytime and often.

• Dormant - has been a while since it has erupted, but could at anytime.

• Extinct, meaning it hasn't erupted in a very long, long time so it probably won't ever again.

Shapes of Volcanoes

• shield volcanoes • composite

volcanoes • cinder cones • lava domes

Volcanic Eruptions Can Trigger:

tsunamis flashfloods

earthquakes mudflows rock falls

Volcanoes can have a very serious effect on the lands and people around them when they erupt

• Buildings are destroyed and people are made homeless.

• People are killed.• Clouds of ash cover plants making them inedible.• Poisonous gases kill people and animals.• Dust causes pneumonia and illnesses to the

survivors.• Dark skies, severe winds and heavy rains may

follow an eruption for months afterwards.

Active volcanoes in the U.S. are found mainly in Hawaii, Alaska, California, Oregon and Washington. The greatest chance of eruptions near areas where many people live is in Hawaii and Alaska. The danger area around a volcano covers about a 20-mile radius. In May 18, 1980, Mount St. Helens erupted in Washington state. It killed 58 people and caused more than $1 billion in property damage.

Where are There Active Volcanoes Today?

Works Cited

• http://images.google.com/images?hl=en&um=1&q=images+of+erupting+volcanoes&sa=N&start=108&ndsp=18

• http://www.woodlands-junior.kent.sch.uk/Homework/mountains/volcanoeruptions.html

• http://images.google.com/images?hl=en&um=1&sa=1&q=images+of+shield+volcanoes&aq=f&oq=

• http://www.fema.gov/kids/volcano.htm