Question 1

The mid-ocean ridges are elevated above the surrounding sea floor because ____________.

Accepted Answer

A)  ridge rocks are hot and therefore of relatively low density 
B)  the lithospheric plates are thickest at the ridges so that they stand up taller 
C)  rising ocean currents leave a vacuum above the ridge 
D)  ridge rocks are mafic, whereas the ocean basin crust consists of ultramafic rock 
A)  ridge rocks are hot and therefore of relatively low density 
B)  the lithospheric plates are thickest at the ridges so that they stand up taller 
C)  rising ocean currents leave a vacuum above the ridge 
D)  ridge rocks are mafic, whereas the ocean basin crust consists of ultramafic rock

Question 2

Why does the surface area of Earth remain constant throughout time?

Accepted Answer

A)  Subduction occurs. 
B)  Rates of sea-floor spreading are equal to sea-floor consumption. 
C)  Plates slip past each other. 
D)  Both a and b are correct. 
E)  Both b and c are correct. 
A)  Subduction occurs. 
B)  Rates of sea-floor spreading are equal to sea-floor consumption. 
C)  Plates slip past each other. 
D)  Both a and b are correct. 
E)  Both b and c are correct.

Question 3

The rate of motion of a lithospheric plate with respect to a stationary hot spot is termed ____________.

Accepted Answer

A)  relative plate velocity 
B)  absolute plate velocity 
C)  lateral plate velocity 
D)  Velocity of this motion cannot be determined. 
A)  relative plate velocity 
B)  absolute plate velocity 
C)  lateral plate velocity 
D)  Velocity of this motion cannot be determined.

Question 4

Why does each continent below have a different polar wander path?

Accepted Answer

A)  Wegener was right: continents move. 
B)  The poles move. 
C)  Both the poles and continents move. 
A)  Wegener was right: continents move. 
B)  The poles move. 
C)  Both the poles and continents move.

Question 5

All basalts younger than 700,000 years old ____________.

Accepted Answer

A)  have normal magnetic polarity 
B)  have reverse magnetic polarity 
C)  are found on the ocean floor very far from mid-ocean ridges 
D)  are found on the continents 
A)  have normal magnetic polarity 
B)  have reverse magnetic polarity 
C)  are found on the ocean floor very far from mid-ocean ridges 
D)  are found on the continents

Question 6

The San Andreas Fault zone in southern California is an example of a ____________-plate boundary.

Accepted Answer

A)  convergent 
B)  divergent 
C)  transform 
A)  convergent 
B)  divergent 
C)  transform

Question 7

The thickness of clay and planktonic microskeletons is greatest ____________.

Accepted Answer

A)  along mid-ocean ridges 
B)  along fracture zones 
C)  at the edges of ocean basins 
D)  in the center of abyssal plains 
A)  along mid-ocean ridges 
B)  along fracture zones 
C)  at the edges of ocean basins 
D)  in the center of abyssal plains

Question 8

As compared to the density of the asthenosphere,the oceanic lithosphere is ____________.

Accepted Answer

A)  always more dense 
B)  always less dense 
C)  initially more dense at the age of formation but eventually becomes less dense 
D)  initially less dense at the age of formation but eventually becomes more dense 
A)  always more dense 
B)  always less dense 
C)  initially more dense at the age of formation but eventually becomes less dense 
D)  initially less dense at the age of formation but eventually becomes more dense

Question 9

It is not the continents that move relative to a fixed pole,but rather it is the pole that moves relative to fixed continents.

Accepted Answer

A) True 
 B)False

Question 10

A "stripe" of a particular magnetic orientation that has a very large width could be indicative of _______________ .

Accepted Answer

A)  a great deal of time spent in a particular magnetic regime 
B)  higher spreading rates than other points in time 
C)  Both a and b are correct. 
D)  None of the above are correct. 
A)  a great deal of time spent in a particular magnetic regime 
B)  higher spreading rates than other points in time 
C)  Both a and b are correct. 
D)  None of the above are correct.

Question 11

The pulling forces that produce the most rapid plate velocities are concentrated at ____________.

Accepted Answer

A)  mid-ocean ridges 
B)  ocean trenches 
C)  continental collision zones 
D)  stable continental interiors 
A)  mid-ocean ridges 
B)  ocean trenches 
C)  continental collision zones 
D)  stable continental interiors

Question 12

At a subduction zone,the downgoing (subducting)plate ____________.

Accepted Answer

A)  is always composed of continental lithosphere 
B)  is always composed of oceanic lithosphere 
C)  may be composed or either oceanic or continental lithosphere 
A)  is always composed of continental lithosphere 
B)  is always composed of oceanic lithosphere 
C)  may be composed or either oceanic or continental lithosphere

Question 13

Regions of the sea floor with positive magnetic anomalies were formed during times when Earth's magnetic field ____________.

Accepted Answer

A)  was exceptionally strong 
B)  was exceptionally weak 
C)  had normal polarity 
D)  had reversed polarity 
A)  was exceptionally strong 
B)  was exceptionally weak 
C)  had normal polarity 
D)  had reversed polarity

Question 14

An average everyday compass depicts inclination.

Accepted Answer

A) True 
 B)False

Question 15

Earthquakes are most frequent near coastlines that are termed ____________.

Accepted Answer

A)  active margins 
B)  passive margins 
C)  aseismic margins 
D)  geodesic margins 
A)  active margins 
B)  passive margins 
C)  aseismic margins 
D)  geodesic margins

Question 16

At a divergent 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 17

By deep-sea drilling,the Glomar Challenger proved the theory that if the model of sea-floor spreading was correct,then sea-floor sediment should be ____________ and ____________ as one moves away from the spreading axis.

Accepted Answer

A)  thicker; younger 
B)  thicker; older 
C)  thinner; younger 
D)  thinner; older 
A)  thicker; younger 
B)  thicker; older 
C)  thinner; younger 
D)  thinner; older

Question 18

Which plant genus dominated glaciated regions during the Late Paleozoic and Early Mesozoic?

Accepted Answer

A)  Ginkgo 
B)  Glossopteris 
C)  Neuropteris 
D)  Quercas 
A)  Ginkgo 
B)  Glossopteris 
C)  Neuropteris 
D)  Quercas

Question 19

A layer of sediment composed of tiny shell fragments and dead plankton that gets thicker as it moves away from mid-ocean ridges and covers most of the ocean floor,but is too thin to have been accumulating since the formation of Earth,suggests that _____________.

Accepted Answer

A)  plankton and shelled organisms evolved recently 
B)  plankton and shelled organisms do not often die and sink to the bottom of the ocean 
C)  the ocean floor is younger toward the mid-ocean ridge 
D)  All of the above are correct. 
A)  plankton and shelled organisms evolved recently 
B)  plankton and shelled organisms do not often die and sink to the bottom of the ocean 
C)  the ocean floor is younger toward the mid-ocean ridge 
D)  All of the above are correct.

Question 20

Iceland is one of the few places in the world that is both above sea level and situated atop a ____________ plate boundary.

Accepted Answer

A)  convergent 
B)  divergent 
C)  transform 
A)  convergent 
B)  divergent 
C)  transform

Exam 2: The Way the Earth Works: Plate Tectonics

The mid-ocean ridges are elevated above the surrounding sea floor because ____________.

Why does the surface area of Earth remain constant throughout time?

The rate of motion of a lithospheric plate with respect to a stationary hot spot is termed ____________.

Why does each continent below have a different polar wander path?

All basalts younger than 700,000 years old ____________.

The San Andreas Fault zone in southern California is an example of a ____________-plate boundary.

The thickness of clay and planktonic microskeletons is greatest ____________.

As compared to the density of the asthenosphere,the oceanic lithosphere is ____________.

It is not the continents that move relative to a fixed pole,but rather it is the pole that moves relative to fixed continents.

A "stripe" of a particular magnetic orientation that has a very large width could be indicative of _______________ .

The pulling forces that produce the most rapid plate velocities are concentrated at ____________.

At a subduction zone,the downgoing (subducting)plate ____________.

Regions of the sea floor with positive magnetic anomalies were formed during times when Earth's magnetic field ____________.

An average everyday compass depicts inclination.

Earthquakes are most frequent near coastlines that are termed ____________.

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

By deep-sea drilling,the Glomar Challenger proved the theory that if the model of sea-floor spreading was correct,then sea-floor sediment should be ____________ and ____________ as one moves away from the spreading axis.

Which plant genus dominated glaciated regions during the Late Paleozoic and Early Mesozoic?

A layer of sediment composed of tiny shell fragments and dead plankton that gets thicker as it moves away from mid-ocean ridges and covers most of the ocean floor,but is too thin to have been accumulating since the formation of Earth,suggests that _____________.

Iceland is one of the few places in the world that is both above sea level and situated atop a ____________ plate boundary.

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

By deep-sea drilling,the Glomar Challenger proved the theory that if the model of sea-floor spreading was correct,then sea-floor sediment should be and as one moves away from the spreading axis.