Section #: 18.1
Magma
Practice Test
1.
When does magma form?
SC.D.1.4.2
a.
when grains have been compacted together
b.
when new minerals form due to chemical changes in the rock
c.
when volcanoes erupt
d.
when temperatures are hot enough to melt rock
Hint
2.
__________ is the internal resistance to flow of a liquid.
SC.D.1.4.2
a.
Viscosity
b.
Weight
c.
Specific gravity
d.
Gravity
Hint
3.
What type of magma has the lowest silica content and is the least explosive?
SC.D.1.4.2
a.
granitic magma
b.
andesitic magma
c.
rhyolitic magma
d.
basaltic magma
Hint
4.
Rhyolitic magma has the __________ viscosity, the __________ gas content and the __________ silica content of any type of magma.
SC.D.1.4.2
a.
lowest, highest, highest
b.
highest, highest, highest
c.
highest, lowest, lowest
d.
lowest, lowest, lowest
5.
When magma reaches Earth's surface it is called __________.
SC.D.1.4.2
a.
intrusive
b.
a batholith
c.
lava
d.
rock
Hint
6.
Why does magma move up to and through Earth's crust?
SC.D.1.4.2
a.
It is cooler than the crust.
b.
It is less dense than surrounding rock.
c.
It is more dense than surrounding rock.
d.
It is more viscous than ocean water.
Hint
