Download Volcanoes

Volcanoes
What is a volcano?
• An opening in the Earth that erupts gases,
ash, and lava.
http://www.youtube.com/watch?v=xExdEXOaA9A
Mountains form when layers of lava,
ash, and other materials build up
around these openings.
How are volcanoes formed?
Convergent volcanoes
• At convergent boundaries, one plate
subducts (sinks) under the other, the plate
melts and magma is forced to the surface.
• These volcanoes have the most violent
eruptions
•
http://www.classzone.com/books/earth_science/terc/content/visualizations/es0902/es0902page01.cfm?chapter_no=visualization
Divergent volcanoes
• At divergent boundaries, plates move apart
and magma rises to the surface.
• Also known as seafloor spreading.
• These eruptions are not as violent
•
http://www.classzone.com/books/earth_science/terc/content/visualizations/es0903/es0903page01.cfm?chapter_no=visualization
http://www.youtube.
com/watch?v=y3YN
pzZWbmU
Lava in the water
Hot Spot
Hot Spots
• Form in the middle of plates.
• As the plate moves, new volcanoes
are created.
http://www.youtube.com/watch?v=
AhSaE0omw9o
2
1
1
2
3
• When the plate
moves, the older
volcanoes lose
their magma
source and are
now dormant
(inactive)
•http://www.classzone.com/books/earth
_science/terc/content/visualizations/es0
904/es0904page01.cfm?chapter_no=vi
sualization
Iceland
• Divergent
Geothermal Activity on Iceland
Surtsey
Natural geothermal pools
Geysers and mud pots
Hawaii
• Hot Spot
http://www.youtube.com/watch?v=bYv6V
5EJAKc
Hot Spot Locations
http://mms.nps.gov/yell/ofvec/exhibits/eruption/volcanoes/hotspot3.htm
Soufriere Hills in Montserrat
• Convergent
If the Pacific Plate stops moving,
what will happed to the Big Island of
Hawaii?
X
It will just keep getting bigger!
What destruction can volcanoes
cause?
Block roadways
Collapse buildings
www.maps.google.com
Lahars
• Mudslides created by
volcanic eruption
• Heat from volcano
melts glaciers on mountain
• Will usually take out
everything in its path
Can cause lung disease
in animals and humans
Ring of Fire
-a chain of convergent volcanoes found
circling the Pacific Ocean
http://www.classzone.com/books/earth_science
/terc/content/investigations/es0810/es0810page
01.cfm?chapter_no=investigation
How fast do plates move computer
investigation
http://www.youtube.com/watch?v=bgRnVhbfIKQ&feature=related
Mount st helens
Volcano Review
Where do we find most volcanoes?
• Near plate boundaries
What are the three types of
volcanoes?
• Convergent, divergent, and hot spot
What and where is the Ring of Fire
• A chain of volcanoes circling the Pacific
Ocean