Glencoe Earth Science

Chapter 12: Volcanoes

Volcanoes

1.
Magma originates in which layer of Earth?
A)mantle
B)crust
C)core
D)inner core
2.
Shield volcanoes are the result of __________.
A)basaltic and andesitic lava flows
B)andesitic lava flows
C)basaltic lava flows
D)granitic lava flows
3.
Composite volcanoes are found mostly where ___________.
A)Earth's plates come together and one plate sinks beneath the other
B)rifts in Earth's surface occur
C)Earth's plates pull apart
D)hot spots in the mantle occur
4.
The difference between basaltic and granitic magma is __________.
A)the amount of silica
B)the color
C)the way it cools
D)the amount of water vapor
5.
A pyroclastic flow is__________.
A)a type of lava flow
B)an opening in the side of a volcano
C)hot volcanic ash and debris that rushes down the side of a volcano
D)another form of precipitation
6.
What is the difference between lava and magma?
A)They originate from different places.
B)They are made of different types of rock.
C)After magma reaches the surface it's called lava.
D)They are different colors.
7.
A volcanic neck is the remains of a(n) ___________.
A)intrusive igneous rock
B)magma flow
C)active volcano
D)eroded volcano
8.
The Hawaiian Islands are formed because of __________.
A)subduction
B)converging plates
C)diverging plates
D)hot spots
9.
Intrusive igneous rocks are those which __________.
A)cool on Earth's surface
B)cool beneath Earth's surface
C)changed over time from one type of rock to another
D)are composed of sediments found in flood beds
10.
What causes magma to rise to the surface?
A)The rock forces the magma upward.
B)Magma is more dense than rock.
C)A force pulls the magma upward.
D)Magma is less dense than rock.
11.
Volcanoes often are found in areas on Earth where __________.
A)rivers are found
B)mountains are found
C)plates fit together perfectly
D)plates collide
12.
Islands like Iceland are often formed due to __________.
A)rifts in the Earth's surface
B)plate movement
C)cooling lava flows
D)all answers are correct
13.
What are batholiths?
A)magma bodies that cool slowly before they reach Earth's surface
B)magma bodies that cool quickly before they reach Earth's surface
C)hot magma flows that cool quickly before they reach Earth's surface
D)hot magma flows that cool slowly before they reach Earth's surface
14.
Granitic magma eruptions are
A)explosive
B)quiet
C)fluid
D)slow
15.
What is a vent?
A)the opening in a volcano
B)the remains of an eroded volcano
C)the steep depression around a volcano's opening
D)a small fissure on the side of a volcano
16.
Calderas form __________.
A)during an eruption
B)continually
C)after an eruption
D)before an eruption
17.
What is the difference between a dike and a sill?
A)They form in the same direction, but are of different sizes.
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 they are created differently.
18.
High levels of silica causes magma to become __________.
A)thinner
B)thicker
C)less dense
D)more fluid
19.
What two factors control the explosiveness of an eruption?
A)the pressure within Earth and plate movement
B)the amount of water vapor and silica in the magma
C)the amount of gases and pressure within Earth's crust
D)the time of year and current weather conditions
20.
A volcano is an opening in Earth that erupts__________.
A)lava
B)ash
C)all answers are correct
D)gases