Question 1

Where do earthquakes occur? Please explain your answer in the context of plate tectonics.Are there exceptions?

Accepted Answer

Earthquakes tend to occur along plate boundaries.This includes convergent,divergent,and transform boundaries.However,occasionally intraplate earthquakes-those occurring away from plate boundaries-do happen.

Question 2

Which earthquake severity scale varies from locality to locality for a single earthquake?

Accepted Answer

A)  the Richter scale 
B)  the Mercalli scale 
C)  the moment magnitude scale 
D)  the surface-wave magnitude scale 
A)  the Richter scale 
B)  the Mercalli scale 
C)  the moment magnitude scale 
D)  the surface-wave magnitude scale B

Question 3

What is an early earthquake warning system,and why does this differ from a short-term earthquake prediction tool?

Accepted Answer

Early warning systems warn of an earthquake in progress,not of an earthquake that will take place in the future.Reliable short-term earthquake predictions do not exist.

Question 4

Determining where roads and building should be built based on where land is stable and less prone to landslide or liquefaction during an earthquake is an example of ________.

Accepted Answer

A)  earthquake zoning 
B)  earthquake engineering 
C)  seismic hazard mapping 
D)  seismic retrofitting 
A)  earthquake zoning 
B)  earthquake engineering 
C)  seismic hazard mapping 
D)  seismic retrofitting

Question 5

During an earthquake,if a hanging wall slides downward relative to a footwall,the fault is termed a ________ fault.Refer to the figure below for an example of such a feature.

Accepted Answer

A)  normal 
B)  reverse 
C)  strike-slip 
D)  thrust 
A)  normal 
B)  reverse 
C)  strike-slip 
D)  thrust

Question 6

Why do deep-focus earthquakes occur along convergent plate boundaries? Why are they absent along divergent or transform boundaries?

Accepted Answer

Convergent plate boundaries result in su

Question 7

Earthquake waves that pass through the Earth's interior are termed

Accepted Answer

A)  interior waves. 
B)  R-waves. 
C)  surface waves. 
D)  body waves. 
A)  interior waves. 
B)  R-waves. 
C)  surface waves. 
D)  body waves.

Question 8

How is the epicenter of an earthquake different from the focus? Why are both terms useful?

Accepted Answer

The focus,or hypocenter,of an earthquake

Question 9

During an earthquake,if the hanging wall slides upward relative to the footwall,the fault is termed a ________ fault if the fault is steep (closer to vertical than horizontal).Refer to the figure below for an example of such a feature.

Accepted Answer

A)  normal 
B)  reverse 
C)  strike-slip 
D)  thrust 
A)  normal 
B)  reverse 
C)  strike-slip 
D)  thrust

Question 10

On average,there are _______occurrences of light and minor earthquakes compared to the number of major and great earthquakes each year.

Accepted Answer

A)  many thousands more 
B)  approximately ten times as many 
C)  about the same number of 
D)  many fewer 
A)  many thousands more 
B)  approximately ten times as many 
C)  about the same number of 
D)  many fewer

Question 11

Compare and contrast P- and S-waves.

Accepted Answer

P-waves and S-waves are both body waves.

Question 12

Most medium- and deep-focus earthquakes occur at

Accepted Answer

A)  convergent-plate boundaries. 
B)  divergent-plate boundaries. 
C)  transform-plate boundaries. 
D)  hot spots. 
A)  convergent-plate boundaries. 
B)  divergent-plate boundaries. 
C)  transform-plate boundaries. 
D)  hot spots.

Question 13

Which type of seismic wave has the fastest velocity?

Accepted Answer

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

Question 14

Body waves include

Accepted Answer

A)  both S- and P-waves. 
B)  both L- and R-waves. 
C)  both surface and interior waves. 
D)  P-waves only. 
A)  both S- and P-waves. 
B)  both L- and R-waves. 
C)  both surface and interior waves. 
D)  P-waves only.

Question 15

Periods of intermittent sliding on a fault because of stress release during episodes of slip,followed by stress buildup to the point that the fault is reactivated,are termed

Accepted Answer

A)  chaotic faulting. 
B)  thrust faulting. 
C)  stick-slip behavior. 
D)  reverse faulting. 
A)  chaotic faulting. 
B)  thrust faulting. 
C)  stick-slip behavior. 
D)  reverse faulting.

Question 16

Seismic retrofitting is the process of

Accepted Answer

A)  predicting future earthquakes. 
B)  strengthening existing buildings and structures. 
C)  mapping areas prone to earthquakes. 
D)  fitting earthquake data after an event to see if it should have been predicted. 
A)  predicting future earthquakes. 
B)  strengthening existing buildings and structures. 
C)  mapping areas prone to earthquakes. 
D)  fitting earthquake data after an event to see if it should have been predicted.

Question 17

Earthquake waves that travel along the Earth's surface are termed

Accepted Answer

A)  interior waves. 
B)  S-waves. 
C)  surface waves. 
D)  body waves. 
A)  interior waves. 
B)  S-waves. 
C)  surface waves. 
D)  body waves.

Question 18

At a minimum,how many seismic stations are necessary to locate the epicenter of an earthquake?

Accepted Answer

A)  one 
B)  two 
C)  three 
D)  four 
A)  one 
B)  two 
C)  three 
D)  four

Question 19

The point on the Earth's surface directly above the point where an earthquake occurs is termed the

Accepted Answer

A)  hypocenter (focus). 
B)  epicenter. 
C)  eye of the fault. 
D)  vertex. 
A)  hypocenter (focus). 
B)  epicenter. 
C)  eye of the fault. 
D)  vertex.

Question 20

Which earthquake scale measures the amplitude of deflection of a seismograph pen,standardized to an idealized distance of 100 km between the epicenter and the seismograph?

Accepted Answer

A)  the Richter scale 
B)  the Mercalli scale 
C)  the moment magnitude scale 
D)  the surface-wave magnitude scale 
A)  the Richter scale 
B)  the Mercalli scale 
C)  the moment magnitude scale 
D)  the surface-wave magnitude scale

Exam 8: A Violent Pulse: Earthquakes

Where do earthquakes occur? Please explain your answer in the context of plate tectonics.Are there exceptions?

Which earthquake severity scale varies from locality to locality for a single earthquake?

What is an early earthquake warning system,and why does this differ from a short-term earthquake prediction tool?

Determining where roads and building should be built based on where land is stable and less prone to landslide or liquefaction during an earthquake is an example of ________.

During an earthquake,if a hanging wall slides downward relative to a footwall,the fault is termed a ________ fault.Refer to the figure below for an example of such a feature.

Why do deep-focus earthquakes occur along convergent plate boundaries? Why are they absent along divergent or transform boundaries?

Earthquake waves that pass through the Earth's interior are termed

How is the epicenter of an earthquake different from the focus? Why are both terms useful?

During an earthquake,if the hanging wall slides upward relative to the footwall,the fault is termed a ________ fault if the fault is steep (closer to vertical than horizontal).Refer to the figure below for an example of such a feature.

On average,there are _______occurrences of light and minor earthquakes compared to the number of major and great earthquakes each year.

Compare and contrast P- and S-waves.

Most medium- and deep-focus earthquakes occur at

Which type of seismic wave has the fastest velocity?

Body waves include

Periods of intermittent sliding on a fault because of stress release during episodes of slip,followed by stress buildup to the point that the fault is reactivated,are termed

Seismic retrofitting is the process of

Earthquake waves that travel along the Earth's surface are termed

At a minimum,how many seismic stations are necessary to locate the epicenter of an earthquake?

The point on the Earth's surface directly above the point where an earthquake occurs is termed the

Which earthquake scale measures the amplitude of deflection of a seismograph pen,standardized to an idealized distance of 100 km between the epicenter and the seismograph?

The Earth in Context

The Way the Earth Works: Plate Tectonics

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

The Wrath of Vulcan: Volcanic Eruptions

Pages of the Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

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

Deep Time: How Old Is Old

A Biography of the 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

Introducing Rocks

A Surface Veneer: Sediments and Soils

The Rock Cycle

The Earth’s Interior Revisited: Insights from Geophysics

Memories of Past Life: Fossils and Evolution

Ever-Changing Landscapes and the Hydrologic Cycle

Prelude: And Just What is Geology?

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