VOLCANOESLauren Dennis, Rebecca Layman, Kyle McGinley,

Stephanie Spears

EARTH’S INTERIOR

Core (inner layer)-temperatures are extremely

high: 3000 degrees Celsius.

Mantle (middle layer)-mainly solid rock, but

there is also a layer of molten rock called magma.

Temperature: 2000 degrees Celsius.

Crust (outer layer)-this is where we live. Includes

ocean, and land.

DIFFERENT PLATES

Eurasian plates, African plate, North American

plate, South American plate, Arctic plate,

Indoaustralian plate, Pacific plate, Nazca plate

Most volcanic eruptions occur along or around

the plate edges

SEA FLOOR SPREADING

This is when the two plates move apart, the rocks

break and form a crack in between the plates.

The magma rises through the cracks and spreads

out along the ocean floor.

As the magma cools, it forms small mountains

called oceanic ridges.

This is a slow and regular process.

STRUCTURE OF A VOLCANO

Vent-opening at the earths surface

Pipe-the passageway of the magma

Crater-the opening at the top of the volcano

Cone-made up of lava, ashes, and cinder (a

fragment of lava) ; sides of the volcano.

TYPES OF VOLCANOES

Composite

Shield

Cinder

Spatter

Complex

DIFFERENT VOLCANOES

http://www.youtube.com/watch?v=DnBggrCdkN0

VOLCANIC ERUPTIONS

They begin when pressure on the magma

chamber forces magma up.

When the magma chamber is completely filled, it

causes different types of eruptions.

One type is described as low water, low silica, and

low flow

Another is low water, high silica, and pasty lava

Another is high water, low silica, and runny lava

Another is high water, high silica, and explosion

VOLCANOES IN THE UNITED STATES

Most volcanoes are found in the western United

States, Hawaii, and Alaska.

RING OF FIRE

The Ring of Fire is a zone of frequent

earthquakes and volcanic eruptions that outlines

the Pacific Ocean

NEGATIVE EFFECTS OF VOLCANOES

They are extremely destructive.

Lava can flow for miles and ash can travel very

far distances as well.

POSITIVE EFFECTS OF VOLCANOES

Volcanoes help enrich soil for farming and in some cases provide reservoirs for the storage of ground water.

The earth's valuable resources are formed in volcanoes. These elements include fluorine, sulfur, zinc, copper, lead, arsenic, tin, molybdenum, uranium, tungsten, silver, mercury, and gold.

Geothermal power is an alternate energy source that is better for the environment and volcanoes provide this to society also.

Volcanoes even help us understand past civilizations and cultures. The lava preserves fossils and artifacts that scientists can learn from.

OUR PHOTOS!

ACKNOWLEDGEMENTS

Mr. Mike Willard, Science Dept. Laboratory

Coordinator – helped us to problem solve the

chemical reaction and necessary ingredients

C. Dianne Phillips, Physical Science Instructor

Content and technical support

NWACC Art Department – gave us clay and

other materials to build the volcano

REFERENCES

http://library.thinkquest.org/17457/english.html

http://pubs.usgs.gov/gip/volcus/page03.html

http://www.umich.edu/~gs265/society/volcanoes.h

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http://www.crystalinks.com/rof.html