Warm-up:
Describe a VOLCANO
01/22/13
Volcanoes
Definition
• A volcano is an opening in a planet's crust,
which allows hot magma, volcanic ash and
gases to escape from the magma chamber
below the surface.
How do they form?
• Volcanoes form often at plate boundaries.
Divergent Boundaries form a .
- Mid-ocean Ridge; or
- Rift Valley
Convergent Boundaries
Oceanic – Continental
Trench
Andes Mountains
Oceanic - Oceanic
Mid-Ocean Ridge
creating an island arc
Japan; Hawaii
How do they form?
• 3) Hot Spots: columns of hot
magma rising from a thin spot
in the Earth’s crust. As the
plate moves, so does the
column of lava, creating island
arcs.
• Real life Example: HAWAII
Types: (nope they aren’t all the
same)
• Shield, Cinder Cone and Composite volcanoes.
So what does it look like?
• http://lavapix.com/#/page/video-volcano/
Shield Volcanoes
• Shield volcanoes slowly erupt. They are large in size and don’t
make huge peaks, they are more like a gently sloping
mountain where one layer of lava cools hardens and another
layer flows on top. Ex: Hawaiian islands.
• Video:
http://www.bing.com/videos/search?q=shield+volcano&view
=detail&mid=258E9BE9D6A967D74421258E9BE9D6A967D744
21&first=0&adlt=strict#view=detail&mid=D7D725889F4B649D
733ED7D725889F4B649D733E
Shield Volcanoes - pictures
Cinder cone Volcanoes
• Produces high viscosity lava with ash, cinders and bombs.
• Explosive eruptions.
• Form a cone like mountain.
Cinder cone volcanoes
• Video:
http://www.bing.com/videos/search?q=cinder+cone+volcano
es&view=detail&mid=B8B605F2874028672739B8B605F28740
28672739&first=0&adlt=strict#view=detail&mid=1CE981DEA3
D53BF3F3061CE981DEA3D53BF3F306
Composite Volcanoes
• Lava flows alternate with explosive eruptions of ash, cinder
and bombs.
• They are tall, cone shaped mountains where layers of lava
alternate with layers of ash.
• EX: Mt. Fuji, Mt. Saint Helens
• Video:
http://www.bing.com/videos/search?q=composite+volcano+&
view=detail&mid=2CDF551F7B6426E174912CDF551F7B6426E
17491&first=0&adlt=strict#view=detail&mid=6B50410E72C30
DFB3A2D6B50410E72C30DFB3A2D
Composite volcanoes (also
called Stratovolcano)
• Quick Write: If you were building a new
house by a volcano, which type of volcano
would be best?
• Done? Continue working on your packet
Reflection: Define SHIELD
volcano and describe the lava
flow that is involved