Chapter 13 Flashcards
(35 cards)
The elastic rebound theory for the origin of earthquakes was first proposed by __________ following the __________ earthquake.
Richter; 1989, Loma Prieta
Mohorovicic; 1964, Anchorage
Giuseppe; 1925, Pizza Lake
Reid; 1906, San Francisco
Reid; 1906, San Francisco
Most earthquakes are produced by:
the federal government
release of elastic energy
atomic explosions
ground water movement
the governor of California jumping up and down
release of elastic energy
Which one of the following statements concerning foci and epicenters is correct?
The epicenter is at the surface directly above the focus where the earthquake initiates.
The earthquake starts at the focus and the rupture extends down to the epicenter.
The fault first cracks at the epicenter and breaks through to the surface at the focus.
The focus is the faulted point on the surface directly above the epicenter.
The epicenter is at the surface directly above the focus where the earthquake initiates.
Which one of the following statements is correct?
P and S waves travel through liquids, but P waves do not travel through solids.
P waves travel through solids; S waves do not.
P and S waves travel through liquids, but S waves do not travel through solids.
S waves travel through solids and P waves travel through liquids.
S waves travel through solids and P waves travel through liquids.
________ have the highest velocities.
Refracted S waves
Secondary waves
Primary waves
Surface waves
Primary waves
The ________ is a direct measure of the distance from a seismic receiving station to the focus of a distant earthquake.
time elapsed between the first P-wave arrivals from the first and last aftershocks
magnitude of the ground acceleration of surface wave passing a receiving station
time interval between the first P-wave and the last surface wave
time interval between the first P and S- wave arrivals
time interval between the first P and S- wave arrivals
Which one of the following is true regarding tsunamis?
They travel as deep-water waves at speeds greater than surface seismic waves but slower than S waves.
They occur in the open ocean, wavelengths are many miles or kilometers and wave heights are only a few feet.
They are started by fault-induced, horizontal shifts in the seafloor that suddenly propel great masses of water in opposite directions.
Their wave heights decrease and wavelengths increase as they move into shallower water.
They occur in the open ocean, wavelengths are many miles or kilometers and wave heights are only a few feet.
On a typical seismogram, ________ will show the highest amplitudes.
P waves
S waves
body waves
surface waves
surface waves
Which of the following foundation materials is most stable during earthquake shaking?
sand and mud
bedrock
water-saturate
unconsolidated moist soil
bedrock
The ________ magnitude scale is a measure of the energy released. It does not directly measure the extent of building damage.
Gutenberg
Reid
Richter
Mercalli
Richter
Why was the Marina District, San Francisco, heavily damaged in the 1906 and 1989 quakes?
The area is built on consolidated rock, causing the shaking to be amplified.
The epicenters of both quakes were right under the district.
Shaking was no more extensive than elsewhere in the city, but the whole district burned following each quake.
Liquefaction and foundation failures were common.
Liquefaction and foundation failures were common.
________ is the maximum possible damage designation on the Mercalli scale.
X
XII
10
12
XII
How was the Turnagain Heights area of Anchorage, Alaska, damaged during the 1964 earthquake?
It burned in a fire set off by broken gas lines.
A weak, subsurface, clay layer failed, resulting in numerous landslides.
It was hit by a large tsunami and then buried by a rock avalanche.
all of the above
A weak, subsurface, clay layer failed, resulting in numerous landslides.
The ________ is the point of origination for an earthquake.
fault point
focus
epizone
seismic centroid
focus
Approximately how much more energy is released in a 6.5 Richter magnitude earthquake than in one with magnitude 5.5?
3000 times
30 times
3 times
300 times
30 times
P waves ________.
have higher amplitudes than do S waves
produce the strongest ground shaking
propagate only in solids
are faster than S waves and surface waves
are faster than S waves and surface waves
The Mercalli Scale is a scale from ________.
I to X that rates the total energy released during the main quake and all aftershocks
I to XII that rates the structural damage due to an earthquake
1 to 10 that rates the energy released by an earthquake
1 to 12 that rates the energy required for faulting to occur
I to XII that rates the structural damage due to an earthquake
What are the smaller magnitude quakes that follow a major earthquake?
epishocks
aftershocks
hyposhocks
exoshocks
aftershocks
The ________ is used to record ground shaking and the earthquake-magnitude scale was invented by ________.
polygraph; Freud
seismograph; Richter
rayoscope; Mercalli
vibroscope; Rector
seismograph; Richter
The epicenter of an earthquake is the ________.
surface location directly above the point where the fault slip initiates
point where the fault cracking initiates
point of most intense, structural damage associated with ground shaking
point where the minimum ground shaking is recorded
surface location directly above the point where the fault slip initiates
The ________ earthquake was accompanied by major damage from tsunamis and ground failures.
Anchorage, AK, 1964
Loma Prieta, CA, 1989
Northridge, CA, 1994
San Francisco, CA, 1906
Anchorage, AK, 1964
________ was struck by three, major earthquakes during the winter and spring months of the years 1811-1812.
Los Angeles, California
New Madrid, Missouri
Nome, Alaska
Charleston, South Carolina
New Madrid, Missouri
Which one of the following best characterizes tsunamis?
They cause the land to ripple and oscillate.
They are easily seen at sea but are lost in the swell and breaking waves along a coast.
They are faster than seismic surface waves.
They have relatively small amplitudes compared to their very long wavelengths.
They have relatively small amplitudes compared to their very long wavelengths.
The ________ earthquake was accompanied by extensive fire damage.
San Francisco, 1906
Mexico City, 1985
Anchorage, 1964
Yerevan, Armenia, 1988
San Francisco, 1906
