Question 1

The average density of the Earth is 2.7 gm/cm3.

Accepted Answer

A) True 
 B)False  False

Question 2

Oceanic crust is _____ continental crust.

Accepted Answer

A)  thinner than 
B)  thicker than 
C)  the same thickness as 
D)  the same composition as 
E)  the same seismic velocity as 
A)  thinner than 
B)  thicker than 
C)  the same thickness as 
D)  the same composition as 
E)  the same seismic velocity as A

Question 3

Because _____ can be accurately calculated, the size and shape of the core can be determined.

Accepted Answer

A)  P-wave paths 
B)  surface wave paths 
C)  gravitational anomalies 
D)  heat flow conditions 
E)  magnetic anomalies 
A)  P-wave paths 
B)  surface wave paths 
C)  gravitational anomalies 
D)  heat flow conditions 
E)  magnetic anomalies A

Question 4

A cavity or body of low-density material causes a _____ pull on a gravity meter relative to average crust.

Accepted Answer

A)  stronger 
B)  greater than the surrounding rock 
C)  weaker 
D)  rapidly increasing 
E)  Gravity can't be measured. 
A)  stronger 
B)  greater than the surrounding rock 
C)  weaker 
D)  rapidly increasing 
E)  Gravity can't be measured.

Question 5

The upper mantle consists of _______.

Accepted Answer

A)  granite 
B)  basalt 
C)  ultramafic rocks 
D)  metamorphic rocks 
E)  sedimentary rocks 
A)  granite 
B)  basalt 
C)  ultramafic rocks 
D)  metamorphic rocks 
E)  sedimentary rocks

Question 6

Seismic tomography uses earthquake waves and computers to study cross sections of the mantle.

Accepted Answer

A) True 
 B)False

Question 7

Recently, geologists have been analyzing ____ generated by tidal friction, ocean waves, and storms to gain an even more detailed image of the crust and upper mantle.

Accepted Answer

A)  energy waves 
B)  light sources 
C)  water movement 
D)  evaporation 
E)  ocean currents 
A)  energy waves 
B)  light sources 
C)  water movement 
D)  evaporation 
E)  ocean currents

Question 8

The average temperature increase in the shallow crust (the geothermal gradient) is about ______ degrees C per kilometer.

Accepted Answer

A)  2 
B)  5 
C)  10 
D)  15 
E)  25 
A)  2 
B)  5 
C)  10 
D)  15 
E)  25

Question 9

The force of gravity between two objects decreases as the square of the distance between the objects increases.

Accepted Answer

A) True 
 B)False

Question 10

The Moho separates the crust from the mantle.

Accepted Answer

A) True 
 B)False

Question 11

One widely accepted hypothesis is that the Earth's magnetic field is created by electric currents within the ______.

Accepted Answer

A)  asthenosphere 
B)  crust 
C)  lower mantle 
D)  liquid outer core 
E)  sun 
A)  asthenosphere 
B)  crust 
C)  lower mantle 
D)  liquid outer core 
E)  sun

Question 12

A gravity meter can be used to explore for metallic mineral deposits.

Accepted Answer

A) True 
 B)False

Question 13

Geologists think that the asthenosphere is molten.

Accepted Answer

A) True 
 B)False

Question 14

The study of ancient magnetic fields is called ____.

Accepted Answer

A)  paleontology 
B)  old magnetism 
C)  Curie point 
D)  paleomagnetism 
E)  magnetic polarities 
A)  paleontology 
B)  old magnetism 
C)  Curie point 
D)  paleomagnetism 
E)  magnetic polarities

Question 15

The presence of an S-wave shadow zone implies that the Earth's core is liquid.

Accepted Answer

A) True 
 B)False

Question 16

The ____ is the transition zone at the core-mantle boundary.

Accepted Answer

A)  Moho 
B)  asthenosphere 
C)  D layer 
D)  perovskite zone 
E)  unnamed surface 
A)  Moho 
B)  asthenosphere 
C)  D layer 
D)  perovskite zone 
E)  unnamed surface

Question 17

High _____ is usually an indication of a magma body or still-cooling pluton near the surface.

Accepted Answer

A)  geothermal gradient 
B)  heat loss 
C)  convection 
D)  conduction 
E)  heat flow 
A)  geothermal gradient 
B)  heat loss 
C)  convection 
D)  conduction 
E)  heat flow

Question 18

The rock record for tens of millions of years indicates that the Earth's magnetic field ____.

Accepted Answer

A)  reverses polarity about every 500,000 years 
B)  is constant in strength and polarity 
C)  did not come into existence until about 1 million years ago 
D)  is a monopole magnet 
E)  has steadily weakened and will be gone in another 10 million years 
A)  reverses polarity about every 500,000 years 
B)  is constant in strength and polarity 
C)  did not come into existence until about 1 million years ago 
D)  is a monopole magnet 
E)  has steadily weakened and will be gone in another 10 million years

Question 19

The boundary that separates the crust from the mantle is the ____.

Accepted Answer

A)  mantle discontinuity 
B)  Mohorovicic discontinuity 
C)  lithospheric discontinuity 
D)  athenospheric discontinuity 
E)  shadow zone 
A)  mantle discontinuity 
B)  Mohorovicic discontinuity 
C)  lithospheric discontinuity 
D)  athenospheric discontinuity 
E)  shadow zone

Question 20

Detailed images provided by _____ suggest that the mantle is heterogeneous, probably due to variations in temperature, composition, and density.

Accepted Answer

A)  p-waves 
B)  shadow zone 
C)  deep drill holes 
D)  seismic reflection 
E)  seismic tomography 
A)  p-waves 
B)  shadow zone 
C)  deep drill holes 
D)  seismic reflection 
E)  seismic tomography

Exam 17: Earths Interior and Geophysical Properties

The average density of the Earth is 2.7 gm/cm3.

Oceanic crust is _____ continental crust.

Because _____ can be accurately calculated, the size and shape of the core can be determined.

A cavity or body of low-density material causes a _____ pull on a gravity meter relative to average crust.

The upper mantle consists of _______.

Seismic tomography uses earthquake waves and computers to study cross sections of the mantle.

Recently, geologists have been analyzing ____ generated by tidal friction, ocean waves, and storms to gain an even more detailed image of the crust and upper mantle.

The average temperature increase in the shallow crust (the geothermal gradient) is about ______ degrees C per kilometer.

The force of gravity between two objects decreases as the square of the distance between the objects increases.

The Moho separates the crust from the mantle.

One widely accepted hypothesis is that the Earth's magnetic field is created by electric currents within the ______.

A gravity meter can be used to explore for metallic mineral deposits.

Geologists think that the asthenosphere is molten.

The study of ancient magnetic fields is called ____.

The presence of an S-wave shadow zone implies that the Earth's core is liquid.

The ____ is the transition zone at the core-mantle boundary.

High _____ is usually an indication of a magma body or still-cooling pluton near the surface.

The rock record for tens of millions of years indicates that the Earth's magnetic field ____.

The boundary that separates the crust from the mantle is the ____.

Detailed images provided by _____ suggest that the mantle is heterogeneous, probably due to variations in temperature, composition, and density.

Introducing Geology, the Essentials of Plate Tectonics, and Other Important Concepts

Atoms, Elements, and Minerals

Igneous Rocks, Intrusive Activity, and the Origin of Igneous Rocks

Volcanism and Extrusive Rocks

Weathering and Soil

Sediment and Sedimentary Rocks

Metamorphism, Metamorphic Rocks, and Hydrothermal Rocks

Time and Geology

Mass Wasting

Streams and Floods

Ground Water

Glaciers and Glaciation

Deserts and Wind Action

Waves, Beaches, and Coasts

Geologic Structures

Earthquakes

The Sea Floor

Plate Tectonics

Mountain Belts and the Continental Crust

Climate Change

Resources

The Earths Companions

Filters

The average density of the Earth is 2.7 gm/cm³.