Location, Location, Location
Anatomy
Eruptions
Types
100
In which location would you most likely find volcanoes? (2 places)
along mid-ocean ridges and where a plate is subducted
100
Before lava reaches the surface, the molten material is called
magma
100
If geologists detect many small earthquakes in the area near a volcano, what can they infer about the volcano?
it is probably about to erupt
100
This volcano is formed from pahoehoe lava in Hawaii
shield volcano
200
Where are volcanoes in subduction zones likely to be found in the US.
Near the Pacific Ocean or West Coast of U.S.
200
When magma hardens in a volcano's pipe, the result will eventually be a landform called a
volcanic neck
200
What is the main hazard from a quiet volcanic eruption?
lava flow
200
Tall, cone-shaped mountains in which layers of lava alternate with layers of ash are called
composite volcano
300
A major volcanic belt known as _____ circles the Pacific Ocean.
the Ring of Fire
300
When many layers of thin, runny lava build up a high, level area, the result is a
lava plateau
300
What is the MAIN factor that accounts for the difference between quiet and explosive volcanic eruptions?
silica content
300
This volcano type produces volcanic ash only and creates an explosive eruption
cinder-cone volcano
400
What is the main difference between dikes and sills?
dikes intersect rock layers underneath the ground and sills are trapped lava pools in between rock layers.
400
The huge hole left by the collapse of a volcanic mountain is called a
caldera
400
What provides the force that causes magma to erupt to the surface?
dissolved gases trapped in the magma
400
Which volcanoes produce pyroclastic flows?
Composite and Cinder-cone
500
Where is the only place where the mid-ocean ridge is exposed on land instead of under water.
Iceland
500
Dome mountains are created by the uplifting of this structure underground
batholith
500
How do volcanoes form in a subduction zone?
As the oceanic plate is subducted, the plate melts and forms magma, which rises toward the surface and erupts as lava, forming volcanoes.
500
Which volcano erupted so violently that it "blew off its top"!
Mount St. Helens
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