Volcanoes
Practice Test
1.
A volcano is an opening in Earth that erupts__________.
a.
ash
b.
gases
c.
all answers are correct
d.
lava
Hint
2.
High levels of silica causes magma to become __________.
a.
more fluid
b.
thinner
c.
thicker
d.
less dense
Hint
3.
What causes magma to rise to the surface?
a.
The rock forces the magma upward.
b.
Magma is less dense than rock.
c.
A force pulls the magma upward.
d.
Magma is more dense than rock.
Hint
4.
What is the difference between a dike and a sill?
a.
They form in the same direction, but they are created differently.
b.
Dikes are formed across horizontal cracks, and sills are formed across vertical ones.
c.
Dikes are formed across vertical cracks, and sills are formed across horizontal ones.
d.
They form in the same direction, but are of different sizes.
Hint
5.
Of the three types of volcanoes, which is the least explosive?
a.
cinder volcanoes
b.
They all have the same level of explosiveness.
c.
shield volcanoes
d.
composite volcanoes
Hint
6.
Convergent plate boundaries __________.
a.
spread apart Earth's surface
b.
create volcanoes that are not as violent as others
c.
don't produce volcanoes
d.
force one plate beneath Earth's surface
Hint
7.
Calderas form __________.
a.
during an eruption
b.
after an eruption
c.
continually
d.
before an eruption
Hint
8.
What are batholiths?
a.
hot magma flows that cool slowly before they reach Earth's surface
b.
hot magma flows that cool quickly before they reach Earth's surface
c.
magma bodies that cool quickly before they reach Earth's surface
d.
magma bodies that cool slowly before they reach Earth's surface
Hint
9.
Shield volcanoes are the result of __________.
a.
andesitic lava flows
b.
granitic lava flows
c.
basaltic lava flows
d.
basaltic and andesitic lava flows
Hint
10.
Magma originates in which layer of Earth?
a.
core
b.
crust
c.
inner core
d.
mantle
Hint
11.
Granitic magma eruptions are
a.
explosive
b.
slow
c.
fluid
d.
quiet
Hint
12.
The difference between basaltic and granitic magma is __________.
a.
the amount of silica
b.
the way it cools
c.
the amount of water vapor
d.
the color
Hint
13.
A volcanic neck is the remains of a(n) ___________.
a.
magma flow
b.
intrusive igneous rock
c.
eroded volcano
d.
active volcano
Hint
14.
Sulfurous gases emitted by volcanoes __________.
a.
are good for the environment
b.
help plants grow
c.
can mix with water vapor and form acid rain
d.
are contained totally within lava flows
Hint
15.
The Hawaiian Islands are formed because of __________.
a.
converging plates
b.
hot spots
c.
diverging plates
d.
subduction
Hint
16.
What is a vent?
a.
the remains of an eroded volcano
b.
the steep depression around a volcano's opening
c.
the opening in a volcano
d.
a small fissure on the side of a volcano
Hint
17.
Volcanoes often are found in areas on Earth where __________.
a.
mountains are found
b.
plates fit together perfectly
c.
rivers are found
d.
plates collide
Hint
18.
A pyroclastic flow is__________.
a.
a type of lava flow
b.
another form of precipitation
c.
an opening in the side of a volcano
d.
hot volcanic ash and debris that rushes down the side of a volcano
Hint
19.
Intrusive igneous rock bodies such as batholiths and sills form when __________.
a.
lava solidifies on Earth's surface
b.
magma solidifies underground
c.
an earthquake occurs
d.
a volcano erupts
Hint
20.
What is the difference between lava and magma?
a.
They are made of different types of rock.
b.
They originate from different places.
c.
They are different colors.
d.
After magma reaches the surface it's called lava.
Hint
