Deck 2: Internal Structure of Earth and Plate Tectonics

Question 1

When did the supercontinent Pangaea start breaking apart?

A)4.6 billion years ago
B)560 million years ago
C)180 million years ago
D)65 million years ago

Answer 1

C

Question 2

Alfred Wegener proposed the idea of sea floor spreading.

Answer 2

False

Question 3

How does the lithosphere differ from the asthenosphere?

A)The lithosphere is stronger than the asthenosphere.
B)The asthenosphere is stronger than the lithosphere.
C)The asthenosphere is part of the core, while the lithosphere is part of the mantle.
D)The asthenosphere is less dense than the lithosphere.

Answer 3

A

Question 4

The Mohorovicic discontinuity represents

A)the boundary between inner and outer cores
B)the boundary between mantle and crust
C)the boundary between lithosphere and hydrosphere
D)the boundary between outer core and mantle

Question 5

Why was Alfred Wegener's hypothesis of continental drift not taken seriously by most geologists?

A)his evidence for former joining of the continents was faulty
B)because it was and is known that continents do not move
C)his mechanism for movement of the continents was faulty
D)he was not a well-respected scientist

Question 6

How do seismologists know the outer core is liquid?

A)P-waves are refracted upon arrival in the outer core
B)S-waves are absorbed upon arrival in the outer core
C)both S-waves and P-waves speed up in the outer core
D)both S-waves and P-waves slow down in the outer core

Question 7

Tectonic plates move about as fast as

A)a car moves on a city street
B)fingernails grow
C)a swallow flies
D)a tortoise walks

Question 8

The rocks of the core are more dense than the rocks of the mantle.

Question 9

The process of isostasy is responsible for

A)moving plates apart at a divergent margin
B)creating volcanoes at a hot spot
C)causing rock uplift in mountain ranges in response to erosion
D)causing compressive stresses at convergent boundaries

Question 10

S-waves accelerate as they enter the outer core.

Question 11

What is the principal difference between the inner core and outer core?

A)The inner core consists mainly of iron and nickel, while the outer core consists mainly of silicate minerals.
B)The inner core consists mainly of silicate minerals, while the outer core consists mainly of iron and nickel.
C)The inner core is solid while the outer core is liquid.
D)The inner core is liquid while the outer core is solid.

Question 12

Crust is consumed at transform boundaries.

Question 13

Transform plate boundaries are marked by

A)volcanic island arcs
B)consumption of oceanic crust
C)creation of oceanic crust
D)two plates sliding relative to one another

Question 14

Which type of earthquake wave moves fastest?

A)P-wave
B)S-wave
C)L-wave
D)R-wave

Question 15

What driving force of plate movement is likely dominant?

A)ridge push
B)slab pull
C)mountain rise
D)valley fall

Question 16

Hot spots are recorded by

A)extensive earthquake hazards
B)mantle rock exposed at the Earth's surface
C)rock from the outer mantle included in volcanic rocks
D)a sequence of volcanic centers younging toward the hot spot

Question 17

At convergent plate boundaries

A)the plate of higher density subducts into the mantle
B)the plate of lower density subducts into the mantle
C)new oceanic crust is created
D)magnetic stripes are generated in oceanic rocks

Question 18

The asthenosphere is stronger than the lithosphere.

Question 19

How did seafloor spreading revive Alfred Wegener's ideas about continental drift?

A)Sea floor spreading relied on new fossil evidence documenting the former joining of the continents.
B)Sea floor spreading provided an explanation for the consumption of oceanic crust at plate boundaries.
C)The topography of the ocean floor demonstrated that mountain ranges on either side of the Atlantic Ocean were formerly joined.
D)Sea floor spreading prevented a viable mechanism for moving the continents.

Question 20

How do magnetic stripes on the ocean floor serve as evidence for seafloor spreading?

A)Their symmetry on either side of the mid-ocean ridge shows that new crust is created, then split.
B)Their patterns show that the Earth's magnetic field reverses every few hundred years, on average.
C)They show that island arc volcanism creates new oceanic crust at the mid-ocean ridges.
D)Their symmetry on either side of mid-ocean ridges shows that transform boundaries are sliding boundaries.

Question 21

The Earth's magnetic field reverses in a regular pattern every few hundred thousand years.

Question 22

The supercontinent Pangaea consisted of Laurasia and ________.

Question 23

The Hawaiian Islands are a volcanic arc atop an oceanic subduction zone.

Question 24

The volcano called ________ is the youngest of the Hawaiian volcanoes.

Question 25

A submarine trench is associated with a convergent boundary.

Question 26

A(n) ________ is a location where three plates border one another.

Question 27

The ________ separates the mantle and the crust.

Question 28

New oceanic lithosphere is generated at mid-ocean ridges.

Question 29

The rocks of the core consist mostly of ________.

Question 30

Deep (>200 km) earthquakes can only be found at a convergent boundary.

Question 31

The concept of seafloor spreading was supported by magnetic polarity stripes on the ocean floor.

Question 32

Convergence of plates can cause ________ forces that build mountain ranges.

Question 33

A change in the direction of wave travel at the core-mantle boundary is called ________.

Question 34

________ can cause uplift in a mountain range through isostatic compensation.

Question 35

Transform boundaries do not generate earthquakes.

Question 36

Only a few transform boundaries (<10) mark the Earth's tectonic plates.

Question 37

Plate tectonic processes can affect climate.

Question 38

At the Curie point, iron-bearing minerals orient themselves parallel to the ________.

Question 39

________-waves pass through the outer core.

Question 40

Yellowstone National Park lies atop a(n) ________.

Question 41

The Cascade Mountains are part of a(n) ________ convergent boundary.

Question 42

The San Andreas Fault is a(n) ________ boundary.