Question 1

The theory of plate tectonics is a theory because it _____________.

Accepted Answer

A)  was discovered so long ago 
B)  is widely accepted 
C)  is not widely accepted 
D)  is commonly regarded as correct 
A)  was discovered so long ago 
B)  is widely accepted 
C)  is not widely accepted 
D)  is commonly regarded as correct

Question 2

Why don't earthquakes occur everywhere?

Accepted Answer

A)  Rocks break and slip most often along plate boundaries. 
B)  Plate interiors do not accommodate much movement. 
C)  Earthquake epicenters speckle the globe randomly. 
D)  Both a and b are correct. 
E)  All of the above are correct. 
A)  Rocks break and slip most often along plate boundaries. 
B)  Plate interiors do not accommodate much movement. 
C)  Earthquake epicenters speckle the globe randomly. 
D)  Both a and b are correct. 
E)  All of the above are correct.

Question 3

The oldest basalts on the ocean floor are about ____________ years old.

Accepted Answer

A)  50 thousand 
B)  4 billion 
C)  200 million 
D)  2.5 million 
A)  50 thousand 
B)  4 billion 
C)  200 million 
D)  2.5 million

Question 4

Consult the figure below.Subduction zones are ____________.

Accepted Answer

A)  convergent-plate boundaries 
B)  divergent-plate boundaries 
C)  transform-plate boundaries 
A)  convergent-plate boundaries 
B)  divergent-plate boundaries 
C)  transform-plate boundaries

Question 5

Without plate tectonics,we would not have _______________.

Accepted Answer

A)  plates in constant motion 
B)  mountain building 
C)  formation of new oceans 
D)  All of the above are correct. 
A)  plates in constant motion 
B)  mountain building 
C)  formation of new oceans 
D)  All of the above are correct.

Question 6

All lithospheric plates are approximately the same size and contain a combination of oceanic and continental crust.

Accepted Answer

A) True 
 B)False

Question 7

Beneath a blanket of sediments,oceanic crust is primarily composed of two rocks,____________ and ____________.

Accepted Answer

A)  granite; diorite 
B)  gabbro; basalt 
C)  sandstone; shale 
D)  slate; gneiss 
A)  granite; diorite 
B)  gabbro; basalt 
C)  sandstone; shale 
D)  slate; gneiss

Question 8

According to Archimedes' principle of buoyancy,an iceberg sinks until _____________.

Accepted Answer

A)  the total mass of the water displaced equals the total mass of the whole iceberg 
B)  the total mass of the iceberg is underwater 
C)  about 60% of the iceberg is underwater 
D)  the total mass of the water displaced equals 80% of the mass of the iceberg 
A)  the total mass of the water displaced equals the total mass of the whole iceberg 
B)  the total mass of the iceberg is underwater 
C)  about 60% of the iceberg is underwater 
D)  the total mass of the water displaced equals 80% of the mass of the iceberg

Question 9

Why is preserved oceanic bedrock only composed of primarily basalt?

Accepted Answer

A)  Magma primarily cools to form basalt. 
B)  Oceanic bedrock does not experience changes in heat that produce different rock types. 
C)  Oceanic bedrock does not experience changes in pressure that produce different rock types. 
D)  All of the above are correct. 
A)  Magma primarily cools to form basalt. 
B)  Oceanic bedrock does not experience changes in heat that produce different rock types. 
C)  Oceanic bedrock does not experience changes in pressure that produce different rock types. 
D)  All of the above are correct.

Question 10

Under the theory of plate tectonics,the plates themselves are ____________.

Accepted Answer

A)  discrete pieces of lithosphere at the surface of the solid Earth that move with respect to one another 
B)  discrete layers of lithosphere that are vertically stacked one atop the other 
C)  composed only of continental rocks that plow through the weaker oceanic rocks 
D)  very thick (approximately one-quarter of Earth's radius) 
A)  discrete pieces of lithosphere at the surface of the solid Earth that move with respect to one another 
B)  discrete layers of lithosphere that are vertically stacked one atop the other 
C)  composed only of continental rocks that plow through the weaker oceanic rocks 
D)  very thick (approximately one-quarter of Earth's radius)

Question 11

As compared to a slowly spreading mid-ocean ridge,a rapidly spreading ridge is ____________.

Accepted Answer

A)  wider 
B)  narrower 
C)  more silicic in lava composition 
A)  wider 
B)  narrower 
C)  more silicic in lava composition

Question 12

Distinctive rock sequences on South America terminate at the Atlantic Ocean but reappear on the continent of ____________.

Accepted Answer

A)  Africa 
B)  Europe 
C)  North America 
D)  Australia 
A)  Africa 
B)  Europe 
C)  North America 
D)  Australia

Question 13

Tectonic plates move at rates that are approximately ____________.

Accepted Answer

A)  1 to 5 cm every 1,000 years 
B)  1 to 15 cm/year 
C)  1 to 15 m/year 
D)  10 to 100 m/year 
A)  1 to 5 cm every 1,000 years 
B)  1 to 15 cm/year 
C)  1 to 15 m/year 
D)  10 to 100 m/year

Question 14

Summed over the entire surface of Earth,____________.

Accepted Answer

A)  the rate of lithospheric production at ridges is greater than the rate of lithospheric consumption at subduction zones 
B)  the rate of lithospheric consumption at subduction zones is greater than the rate of lithospheric production at ridges 
C)  rates of lithospheric production and consumption are equal 
A)  the rate of lithospheric production at ridges is greater than the rate of lithospheric consumption at subduction zones 
B)  the rate of lithospheric consumption at subduction zones is greater than the rate of lithospheric production at ridges 
C)  rates of lithospheric production and consumption are equal

Question 15

The average thickness of continental lithosphere is about ____________.

Accepted Answer

A)  30 km 
B)  60 km 
C)  150 km 
D)  10,000 km 
A)  30 km 
B)  60 km 
C)  150 km 
D)  10,000 km

Question 16

The youngest sea floor occurs ____________.

Accepted Answer

A)  along passive margins 
B)  along active margins 
C)  along mid-ocean ridges 
D)  randomly over the entire ocean basin 
A)  along passive margins 
B)  along active margins 
C)  along mid-ocean ridges 
D)  randomly over the entire ocean basin

Question 17

According to the figure below,fracture zones lay roughly ___________ to mid-ocean ridges.

Accepted Answer

A)  perpendicular 
B)  parallel 
C)  adjacent 
D)  at an obtuse angle 
A)  perpendicular 
B)  parallel 
C)  adjacent 
D)  at an obtuse angle

Question 18

At a convergent-plate boundary (shown below),two opposed plates ____________.

Accepted Answer

A)  move toward one another 
B)  move away from one another 
C)  slide past one another 
A)  move toward one another 
B)  move away from one another 
C)  slide past one another

Question 19

If we mentally align the continents to fit Wegener's concept of Pangaea,evidence of Late Paleozoic glacial deposits ____________.

Accepted Answer

A)  is more difficult to explain than in the modern continental configuration 
B)  is much more readily explained than in the modern continental configuration 
C)  makes very little sense in either the Pangaea configuration or the modern configuration 
A)  is more difficult to explain than in the modern continental configuration 
B)  is much more readily explained than in the modern continental configuration 
C)  makes very little sense in either the Pangaea configuration or the modern configuration

Question 20

Without which of the following principles would it be impossible to drive plate motion?

Accepted Answer

A)  Plastic material is pushed downslope by the mass of the material at higher elevations. 
B)  Once plastic material starts to sink, it will bring the entire mass of the material with it. 
C)  Plastic material always flows away from its source. 
D)  Both a and b are correct. 
E)  Both b and c are correct. 
A)  Plastic material is pushed downslope by the mass of the material at higher elevations. 
B)  Once plastic material starts to sink, it will bring the entire mass of the material with it. 
C)  Plastic material always flows away from its source. 
D)  Both a and b are correct. 
E)  Both b and c are correct.

Exam 2: The Way the Earth Works: Plate Tectonics

The theory of plate tectonics is a theory because it _____________.

Why don't earthquakes occur everywhere?

The oldest basalts on the ocean floor are about ____________ years old.

Consult the figure below.Subduction zones are ____________.

Without plate tectonics,we would not have _______________.

All lithospheric plates are approximately the same size and contain a combination of oceanic and continental crust.

Beneath a blanket of sediments,oceanic crust is primarily composed of two rocks,____________ and ____________.

According to Archimedes' principle of buoyancy,an iceberg sinks until _____________.

Why is preserved oceanic bedrock only composed of primarily basalt?

Under the theory of plate tectonics,the plates themselves are ____________.

As compared to a slowly spreading mid-ocean ridge,a rapidly spreading ridge is ____________.

Distinctive rock sequences on South America terminate at the Atlantic Ocean but reappear on the continent of ____________.

Tectonic plates move at rates that are approximately ____________.

Summed over the entire surface of Earth,____________.

The average thickness of continental lithosphere is about ____________.

The youngest sea floor occurs ____________.

According to the figure below,fracture zones lay roughly ___________ to mid-ocean ridges.

At a convergent-plate boundary (shown below),two opposed plates ____________.

If we mentally align the continents to fit Wegener's concept of Pangaea,evidence of Late Paleozoic glacial deposits ____________.

Without which of the following principles would it be impossible to drive plate motion?

The Earth in Context

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

The Wrath of Vulcan: Volcanic Eruptions

Pages of Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

A Violent Pulse: Earthquakes

Crags, cracks, and Crumples: Crustal Deformation and Mountain Building

Deep Time: How Old Is Old

A Biography of Earth

Riches in Rock: Energy and Mineral Resources

Unsafe Ground: Landslides and Other Mass Movements

Streams and Floods: the Geology of Running Water

Restless Realm: Oceans and Coasts

A Hidden Reserve: Groundwater

Dry Regions: the Geology of Deserts

Amazing Ice: Glaciers and Ice Ages

Global Change in the Earth System

Rock Groups

A Surface Veneer: Sediments and Soils

The Rock Cycle

The Earths Interior Revisited: Insights From Geophysics

Memories of Past Life: Fossils and Evolution

An Introduction to Landscapes and the Hydrologic Cycle

Filters

Beneath a blanket of sediments,oceanic crust is primarily composed of two rocks, and .

According to the figure below,fracture zones lay roughly _ to mid-ocean ridges. $According to the figure below,fracture zones lay roughly _ to mid-ocean ridges.$