Unit 2: Earthquakes (smart book assignment questions)
The earthquake disaster in Haiti resulted in so many deaths from building collapse for the primary reason that ______. it is impossible to build cheap earthquake-resistant homes this country is extremely poor the earthquake was so large
this country is extremely poor
A seismic sea wave is known as a(n)
tsunami
An earthquake warning issued by the Earthquake Prediction Panel of the U.S. Geological Survey might ______. (Choose all that apply.) include the likelihood of a certain sized earthquake during a general time frame be a general notice to residents that a fault zone exists include the nature of associated hazards include the exact date and time an earthquake will happen
include the likelihood of a certain sized earthquake during a general time frame be a general notice to residents that a fault zone exists include the nature of associated hazards
Measuring the ___________ of an earthquake involves the effects on human and structures.
intensity
A common hazard associated with earthquakes, ____________ are a serious threat in hilly areas with unstable slopes.
landslides
Engineering utility lines to be more flexible will reduce the amount of damage from ______ that occur during earthquakes. shaking liquefaction large offsets tsunami
large offsets
During an earthquake, wet soil can be shaken, losing its cohesion and strength in a process called ______. liquefaction quicksanding condensation
liquefaction
The _____________ of an earthquake is a measure of the energy released and is related to the amount of ground motion.
magnitude
Power lines and pipelines of all scales can be made ______ so as not to break from ground motion during earthquakes. more rigid bigger more flexible
more flexible
Earthquakes at oceanic divergent boundaries (ridges) are ______ in depth. shallow shallow, intermediate, and deep shallow and intermediate
shallow
Movement along a(n) __________-slip fault is parallel to the strike, whereas displacement in a(n) ____________-slip fault is parallel to the dip.
strike dip
The megathrust boundary between the Indian and Burma plates, along which the 2004 Sumatra earthquake occurred, is a ____________ zone. (Use just one word for your answer.)
subduction
Deep-focus earthquakes occur along the west coast of South America, in Japan, and in Indonesia because all of those locations are ______. hot spots subduction zones spreading centers
subduction zones
Damage from ground shaking during an earthquake comes primarily from ______ waves. S surface P
surface
The types of seismic waves shown here are known as _____________ waves and are larger in amplitude than body waves.
surface
Measuring the energy released from an earthquake using the moment magnitude scale takes into account ______. (Choose all that apply.) the amount of fault displacement the amount of force involved the length of fault displaced the last time the fault was displaced the age of the fault
the amount of fault displacement the amount of force involved the length of fault displaced
How large in magnitude was the 2004 Sumatra earthquake? 4.9 6.2 7.8 9.1
9.1
Which is the best definition for a fault? A location where earthquakes occur A break in the lithosphere A break in the lithosphere along which movement occurs A weakness in the earth's crust
A break in the lithosphere along which movement occurs
What is a seismic gap? A particularly large space between opposing fault blocks A geographic location that has never had and will never have an earthquake Areas along a fault with infrequent seismic activity A large vertical motion that occurs during an earthquake
Areas along a fault with infrequent seismic activity
What type of damage is directly caused by earthquake fault movement? Broken utility lines, road, and bridges Fires Building collapse
Broken utility lines, road, and bridges
Choose all of the phenomena that have been scientifically measured that may precede an earthquake. Abnormal animal behavior Geophysical changes to rocks Groundwater level changes Ground surface movement Dangerous electrical storms
Geophysical changes to rocks Groundwater level changes Ground surface movement
Using the intensity map of a 2017 Meixcan earthquake as an example, what can we say about the relationship of intensity to distance from epicenter? Intensity has no relationship to distance from the earthquake epicenter. Intensity varies with distance from the epicenter: there are no other factors involved. Intensity, in general, does vary with distance from the epicenter but there are some exceptions: there are other factors involved.
Intensity, in general, does vary with distance from the epicenter but there are some exceptions: there are other factors involved.
Which of the following describe earthquake intensity? (Choose all that apply.) It describes the effect an earthquake has on humans and structures. It has little scientific use. The Mercalli scale is used. It is a subjective measurement. The Richter scale is used.
It describes the effect an earthquake has on humans and structures. The Mercalli scale is used. It is a subjective measurement.
Which of the following describe the Richter scale? (Choose all that apply.) It was developed in Japan over 500 years ago using simple mechanical devices. It is the magnitude scale currently favored by scientists. It measures earthquake magnitude. It is logarithmic.
It measures earthquake magnitude. It is logarithmic.
Why does the U.S. Geological Survey now use moment magnitude, instead of the Richter magnitude, to report on earthquakes? It takes into account more data in measuring the energy released. Moment magnitude is the traditional way to measure earthquakes. It is cheaper to measure moment magnitude.
It takes into account more data in measuring the energy released.
What is the tectonic setting that was responsible for the disastrous 2004 Sumatra earthquake? It's a ocean ridge system. It's a subduction zone. It's a continental collision.
It's a subduction zone.
Earthquake intensity is measured using the _________________ scale.
Mercalli
Which of the following best describes the arrival of P and S waves at a recording station from a single earthquake? S waves always arrive just slightly before P waves do. Depending on distance from the earthquake, either P waves or S waves may arrive first. P waves and S waves arrive at the same time. No matter where the waves are recorded, the P waves always arrive first.
No matter where the waves are recorded, the P waves always arrive first.
What type of seismic wave will arrive at a recording station first from a given earthquake? P wave Surface wave S wave
P wave
Assuming that faults behave in an earthquake cycle is based upon two factors. Choose these two from below. Plates move at a fairly constant rate. The short-term movement of lithospheric plates is unpredictable. Rocks along a fault zone have particular physical properties. Earth materials in fault zones change drastically with each subsequent earthquake.
Plates move at a fairly constant rate. Rocks along a fault zone have particular physical properties.
P waves
Primary waves; compression and expansion motion
Which of the following measurement scales was developed in the early 1900s in California and based mainly on shallow-focus earthquakes? Moment magnitude Intensity Richter
Richter
The Mercalli scale employs ______ to describe earthquake intensity. numbers 1-5 Roman numerals I - XII general descriptions
Roman numerals I - XII
What is the name of the device used to measure earthquake activity? Vibratogram Tiltometer Shake-o-meter Seismograph
Seismograph
S waves
Shear waves; side-to-side motion
How does the U.S. Geological Survey decide to issue an earthquake warning? Congress votes on a recommendation given by the Earthquake Prediction Panel. The Earthquake Prediction Panel makes a recommendation to the director of the survey. All members vote on a recommendation submitted by the director of the survey.
The Earthquake Prediction Panel makes a recommendation to the director of the survey.
What is earthquake magnitude? The amount of damage caused by an earthquake The amount of energy released associated with ground motion How long an earthquake lasts How people experience an earthquake
The amount of energy released associated with ground motion
What would happen to a coastline that was suddenly shifted downward during an earthquake? The land would flood or become submerged. It would quickly fill with groundwater. A dry valley would be formed.
The land would flood or become submerged.
Which of the following describe aftershocks? (Select all that apply.) They occur after a primary earthquake. They are more severe than the principal earthquake. They can cause a lot of damage to buildings that are already compromised. They occur within one day of the primary earthquake.
They occur after a primary earthquake. They can cause a lot of damage to buildings that are already compromised.
What is an earthquake? The sudden release of stress in the lithosphere Movement along a fault Slow, gradual movement of earth's tectonic plates
The sudden release of stress in the lithosphere
Which of the following describe tsunamis? (Choose all that apply.) They are caused by ocean floor earthquakes. A single tsunami can travel around the globe. They travel very fast. In the open ocean, they can reach 15 m in height.
They are caused by ocean floor earthquakes. A single tsunami can travel around the globe. They travel very fast.
Which of the following describe surface waves? (Choose all that apply.) They are larger in amplitude than body waves. They cause little damage. They travel through the earth. There are two types.
They are larger in amplitude than body waves. There are two types.
What is liquefaction? The obliteration of a building from shaking The creation of a new state of semisolid material along a moving fault plane When wet soil is shaken and loses its strength When ground motion moves dry land vertically to below sea level
When wet soil is shaken and loses its strength
Just as the name implies, ______________ are small earthquakes that occur after a primary earthquake.
aftershocks
An early warning of an earthquake, issued 10 seconds before the arrival of seismic waves, would ______. (Select all that apply.)
allow trains to be slowed and/or stopped give enough time to turn off pipelines allow people to get to a safer location
Most earthquakes occur ______. (Choose all that apply.) along plate boundaries in the asthenosphere in North America in belts
along plate boundaries in belts
P waves and S waves are _____________ waves created during an earthquake that travel through earth's interior.
body
Earthquakes on major fault systems may behave in a periodic fashion described as an earthquake ___________. This means that stress builds up and is released over regular time intervals.
cycle
Elastic rebound describes the behavior of rocks that ______ when stress is applied to them. stretch like a rubber band deform, break, and are displaced behave like a liquid
deform, break, and are displaced
Earthquakes can be categorized by _____________ of focus: shallow (0-70 km), intermediate (70-350 km), and deep (350-700 km).
depth
Intensity does generally decrease with distance from an earthquake's epicenter; this map of an earthquake in South Carolina shows that other factors such as underlying geology ______. disrupts the general pattern does not disrupt the general pattern
disrupts the general pattern
Changes in groundwater levels, ground surface topography, and the geophysical properties of rocks are all ________________ precursors.
earthquake
When stress builds up in the lithosphere, either along an existing fault or in unfractured rocks, the rocks will eventually fail in a sudden release of energy called a(n)
earthquake
The strain on a segment of a fault builds up over time and is released suddenly in an earthquake. This pattern repeats itself at a fairly constant rate in a(n) ______. seismic series rupture round earthquake cycle
earthquake cycle
True or false: Buildings located on soil will receive less damage during an earthquake than those built on solid rock.
false
True or false: The San Andreas fault is a single, cracked segment of the lithosphere.
false
A break in the earth's lithosphere along which movement occurs is a(n)
fault
Broken power and water lines, cracked roads and bridges, and broken buildings are all the result of ______ during an earthquake. shaking tsunamis fault movement falling debris
fault movement
As evidenced by the destruction this hazard caused after the 1906 San Francisco earthquake, ________________ occurs when gas lines are broken due to shaking.
fires
Sudden subsidence along a coast during an earthquake can cause temporary _______________ or permanent submergence.
flooding
The hypocenter, or ____________, of an earthquake is the location on the fault where movement is initiated. The ___________ is the point on earth's surface directly above the hypocenter.
focus epicenter
Displacement in a strike-slip fault is ______, whereas displacement in a dip-slip fault is ______. evident; hard to see small; great horizontal; vertical vertical; horizontal
horizontal; vertical
Most, but not all, earthquakes occur along ________________boundaries.
plate
Changes in the way land is used and zoned along fault systems, as well as using innovative construction practices, are ways that _____________ damage from earthquakes can be reduced.
property
With all other variables being equal, structures built on ________________ will fare better in an earthquake compared to those built on loose materials such as soil. (Use just one word for your answer.)
rock
Energy released during an earthquake travels in different types of __________ waves away from the focus.
seismic
Energy stored up and then released during an earthquake travels away from the focus in ______ waves. sound surface seismic shear
seismic
A(n) ______________ is used to measure the ground motion created by an earthquake.
seismograph
The building shown here that has collapsed was inadequately built to withstand the ______________ associated with an earthquake.
shaking