Earthquakes (Anthro)
Why do the stations in between the San Andreas Fault and the Calaveras fault appear to have no motion? One of the students hired to conduct the GPS survey made a mistake while treating the data. The San Andreas fault and the Calaveras fault are conflicting, forcing blocks to move in opposite direction, which makes the block in the middle look static. Correct Answer They have no relative motion with respect to the reference station that is located close to San Jose We are not measuring displacement at those stations for long enough and we cannot determine their motion yet.
They have no relative motion with respect to the reference station that is located close to San Jose
Select the best 3 strategies to reduce earthquake vulnerability.
creating zoning laws to restrict building where the hazard is greatest implementing an earthquake warning system implement construction strategies that make buildings more resistant to shaking damage
The orange box and orange arrow in this picture are both identifying what potentially problematic structural feature of this house?
cripple wall
Pick the 3 things on this list that count as a hazard.
earthquakes landslides tsunami
Below is an image of 2 possible earthquake scenarios on the Hayward Fault as generated by a simulation of what a major Hayward Fault earthquake could be like (we will learn more about this "Haywired Scenario" later in the course). The white region in the center of each panel corresponds to the area of the fault that could rupture (i.e. slip) in an earthquake. Do the colored regions represent moment, magnitude or shaking intensity?
intensity
Seismic signals can be used to identify and locate:
major rockfall nuclear tests explosions pit blasts cruise ship crashes
To access Shale gas you need to:
make fractures underground so the gas is released
Induced Seismicity can be caused by... (select all that apply)
mining CO2 sequestration oil extraction dam building
What is the evidence they use to make their argument?
- The titanic strike and the assassination had occurred both on the same day April 14th between 10 -12. - Earthquake in San Francisco on July 22nd, 2020. Titanic had 2200 people die and Lincoln died at 7:22.
About how long did it take for the Indian Ocean tsunami of 2004 to reach the United States East Coast?
1 day, 5 hours
What is InSAR? Another name for GPS satellites. Correct Answer A technique using radar data from some satellites that one can use to measure the ground deformation. Satellites that orbit the Earth and take pictures of the ground. Very sensitive seismometers, flying on satellites and can measure very specific seismic waves that are released in the atmosphere.
A technique using radar data from some satellites that one can use to measure the ground deformation.
Why can't scientists predict the occurrence of earthquakes?
All of the processes that govern the occurrence of earthquakes is not known.
Where are earthquakes more likely to occur? At the boundaries of the tectonic plate, where they interact with other plates. In the middle of the plates. Just where two plates are colliding into each other. Only if a major city and a volcano are around
At the boundaries of the tectonic plate, where they interact with other plates.
If the Alquist Priolo Act is a law in California that states that no building may be built on an active fault, why is it legal for Memorial Stadium to be where it is?
It was grandfathered in, on account of having been first built before the law passed.
What happened to the Metsamor nuclear power plant in USSR/Armenia after the earthquake?
It was initially shut down, but due to lack of power, the reopened it in 1995 despite the seismic risk.
Where did the largest tsunami ever recorded occur? What was the cause?
Lituya Bay, Alaska, 1958. Caused by landslide triggered by the Fairweather Fault
What are some natural warnings for tsunamis when the source is nearby?
Long lasting earthquake shaking, unusual roar unusual ocean behavior,
Which of the following type of earthquakes would likely cause the largest tsunami?
Megathrust
There have been 3 UCERF reports. Each one provided a likelihood of a M6.7+ earthquake on the Hayward Fault within 30 years of the publication date. The 2003 model forecast a 27% chance. The 2008 forecast estimated a 31% likelihood, and the 2015 estimated 33%. What is one significant reason the likelihood changed with time?
More stress has built up over time since there has not been a big earthquake
What action should you take during an earthquake if you are outside?
Move away from buildings, power lines, and trees
What are the four types of seismic waves? (Select more than one) Y or Yay waves which move through the surface of the ocean Rayleigh waves which travel near Earth's surface S or Shear waves which move through the Earth's interior Love waves which travel near Earth's surface P or Longitudinal waves which move through the Earth's interior Hate waves which travel through the atmosphere
Rayleigh waves which travel near Earth's surface S or Shear waves which move through the Earth's interior Love waves which travel near Earth's surface P or Longitudinal waves which move through the Earth's interior
What can you do to reduce your risk to earthquakes?
Reduce your vulnerability
Which type of seismic wave can't travel through liquid? Body waves P waves S waves
S waves
What action should you take during an earthquake if you in a car?
Safely slow down, pull to the side of the road, and put the break on
What are the two components that define the seismic risk?
Seismic vulnerabilty and seismic hazard.
What can be done with a few seconds of warning? (Choose the best 6)
Shut down fragile electronic or technical processes Slow down trains Surgeons can take their tools out of their patients Individuals can take protective action, like drop, cover, and hold on. Stop elevators at the nearest floor and open the doors Automatically open the garage doors for fire stations
People have proposed many possible indicators to predict earthquakes. So far none of them have worked. Why?
Some of them have been observed before an earthquake, but none have consistently been observed before every earthquake.
Why are there so many earthquakes in Alaska? - There are so many earthquakes because they are all smaller magnitude and are releasing less energy with each one. - The lithospheric plates around Alaska are more brittle than other tectonic plates and break more easily, leading to more recorded earthquakes. - The earthquakes are all volcanic, which tend to be the strongest kind. The Pacific Plate is moving quickly and subducting under the North American continent.
The Pacific Plate is moving quickly and subducting under the North American continent.
he street made safe in case of earthquakes?
The bridge's moorings contain sliding plates that can accommodate without snapping the bridge
What is an example of a possible "interdependency" associated with an earthquake on the Hayward fault?
The earthquake breaking water pipes, meaning that less water is available for emergency services to combat fires
Three stations recorded and earthquake. Using the difference in arrival times between the primary and secondary waves, a distance to source has been calculated for each station. In the map diagrams below, the small squares are the stations, and the circles that surround them represent the distance away that the earthquake must have occurred relative to each of them. Which one of these four diagrams has the epicenter (star) correctly located?
The epicenter is located where all three circles touch
What is one reason UC Berkeley's chose to build the university where it is?
The fog gathered and condensed against the hills and caused Strawberry Creek to be a year-round water source
Taking into account your answers to the previous two questions, what is a basic premise of forecasts like UCERF? Complete this statement: As the criteria (time frame, magnitude range, etc.) you use to make a forecast become more specific, then:
The forecasted probabilities will become smaller
On average on in California's crust, primary waves travel 6 km/s. If an earthquake occurs and a station 60 km away records the primary waves 12 seconds after the rupture starts, what happened? The medium through which the waves travelled had a physical characteristic that caused them to slow down The medium through which the waves travelled had a physical characteristic that caused them to speed up The earthquake released slower than normal waves The earthquake released faster than normal waves
The medium through which the waves travelled had a physical characteristic that caused them to slow down
Why is the structural feature from the previous question dangerous in an earthquake?
This feature is not very strong when shaken side to side, and the house can potentially slide off its foundation or collapse down
Creeping waves are a type of body wave True False This is not a real type of seismic wave
This is not a real type of seismic wave
Which is the correct relationship between hazard, risk, and vulnerability?
hazard * vulnerability = risk
Now let's think about this in the context of earthquake forecasts. Consider these 3 tables, which are from the most recent forecasting model for the state of California, UCERF3. The probability of a M6.7+ earthquake in the next 30 years is greater for the entire state than the Bay Area alone. What makes the difference?
he size of the area considered is different
Earthquakes at the Hoover dam were caused by:
increased water pressure that lead to coseismic slip along faults
What is the source of Iceland's volcanism? it is a rare combination setting where a hotspot intersects with a mid ocean ridge It sits on a hotspot like Hawai'i None of these Correct! it sits on the Mid-Atlantic ridge, where two oceanic plates are spreading apart scientists are not sure It is the result of subduction like the Cascadian volcanoes
it sits on the Mid-Atlantic ridge, where two oceanic plates are spreading apart
Natural forces that can cause earthquakes include... (Select all that apply)
magma transport glacial unloading tectonic forces
The 2002 Denali earthquake is a good example of engineering successfully reducing the vulnerability of the area.
True
The Aceh national conflict took an unexpected turn with the reach of an agreement soon after the Boxing Day Tsunami in 2004.
True
The age of the ocean floor is symmetric with respect to the axis of a mid-oceanic ridge. True False
True
In which country did the Spitak earthquake occur
Union of Soviet Socialist Republics (USSR)
What is the name of the government agency responsible for monitoring earthquake activity in the United States?
United States Geological Survey
What is the name of the government agency responsible for monitoring earthquake activity in the United States? United States Geological Survey United States Geographical Survey United States General Surveillance United States Global Security
United States Geological Survey
What causes most earthquakes on the east coast of the United States? Uplift of the lithosphere after ice sheets had melted. Transform faults that are not as frequently active. Magma chambers below the surface from an old inactive hotspot. Converging continental-continental plate boundary.
Uplift of the lithosphere after ice sheets had melted.
What is a "triple junction"? Where hotspots, spreading centers, and subduction zones occur in close proximity Where three plates meet. Where three transform boundaries intersect Where three types of plate boundaries occur
Where three plates meet.
Approximately what is the current speed of plate motion? a few centimeters a year tens of meters a year a few millimeters a year a few meters a year
a few centimeters a year
Pick 3 sources of vulnerability.
a population of 30 million living in coastal cities that can experience a tsunami weak building codes surfing in shark infested waters
What kinds of observations are required to make earthquake prediction possible?
all of these are necessary
The instructor uses the term 'inertia' when explaining how seismometers work. What is inertia? an object's resistance to being moved. the speed at which an object moves how heavy an object is the property that describes in what direction an object is most easily moved
an object's resistance to being moved.
Baja California is: Subducting under the Cocos Plate moving northwest, away from mainland Mexico Moving southeast, towards mainland Mexico subducting under the North American Plate
moving northwest, away from mainland Mexico
Match each piece of this forecast with the correct category of forecasting component. A 20% chance of a snowstorm in Boulder, Colorado on Friday, November 19. 20% chance snowstorm Boulder, Colorado Friday, Nov 19
probability event location/area timeframe
Which of the following could seismic waves be subject to? stress, strain, deformation reflection, refraction, scattering reflection, seismicity, vibration temperature, pressure, dissolution
reflection, refraction, scattering
Pick 2 examples of risk.
residents of the Bay Area have a 0.003% chance of getting stuck in an elevator in a major Hayward Fault earthquake 1 in a million chance of being stung by a bee
Why did the engineers have a difficult time finding the Hayward fault under the Foothills residential halls?
revious landslides had covered the fault
The Hayward fault
runs right under Memorial stadium
For people who do receive a warning before heavy shaking begins, about how much time should they expect (on average) to have to respond or take protective action?
seconds
What is UC Berkeley doing?
taking managable, incremental steps to improve seismic building safety on campus
The moment of an earthquake is related to the amount of energy released by the quake, but it isn't directly equivalent. What are some key parameters that go into the computation of moment? the depth of the focus and the type of rock that makes up the fault face Correct! the area of the fault that rupture, and how far that patch moved The volume of rock that was displaced the amplitude of the seismic waves recorded 100 km away and the time between the arrival of the P and S waves the amount of time that the fault had been locked prior to the rupture
the area of the fault that rupture, and how far that patch moved
Which is NOT true about earthquakes and mining?
excessive drilling can cause additional fractures
How quickly a seismic station could get its data to a central server so that it could be available for computation is referred to as what?
Data latency
Identify what this statement is an example of: 'An earthquake has begun under Oakland and residents of San Jose can expect to experience strong shaking in 10 seconds'
Early Warning
Select the true statement.
Earthquake early warning is neither a prediction nor an earthquake forecast.
What are the top three causes of tsunamis (in order of highest to lowest percentage of tsunamis caused)?
Earthquakes, landslides, volcanoes
What are seismic waves? Elastic waves that can result from the sudden release of energy from an earthquake Waves that rebound and cause earthquakes Sound waves resulting from tsunamis
Elastic waves that can result from the sudden release of energy from an earthquake
The Tohoku-Oki earthquake in Japan that occurred in March 2011 is the largest earthquake ever recorded in the history of seismology.
False
The Tohoku-Oki earthquake in Japan that occurred in March 2011 is the largest earthquake ever recorded in the history of seismology. False Correct! It was the most powerful earthquake ever recorded in Japan, and the fourth most powerful earthquake in the world since modern record-keeping began in 1900. True
False
The seismic signature of a building collapse is identical to an earthquakes seismic signature.
False
There is little to no seismic activity in East California/the Sierras. True Correct Answer False
False
True or False: Seismic waves cannot accelerate as they travel through a medium. True False
False
True or False: All earthquakes are associated with a plate boundary. True False
False, Yes, some earthquakes are involved with volcanoes, landslides, and other geological processes
True or False: Because San Francisco Bay is very shallow the tsunami risk is low.
False, risk is low because not much energy can travel through in such a short time through Golden Gatete
California has a 99% chance of seeing a magnitude 6.7 earthquake or greater. Is this statement a prediction or a forecast?
Forecast
Identify what this statement is an example of: 'There is a 7% chance of a M8+ earthquake in the LA region before 2043'
Forecast
Which modern equipment can one use to measure the speed of the plates at the surface of the Earth, and their relative motion between each other? GPS Seismometer Binocular/Telescope Magnetometer
GPS
Select the 2 campus buildings on this list who have Good seismic ratings.
Hazardous Materials Facility Barrows Hall
How many credible tsunamis have been recorded in California?
~90
Which of the following is NOT true of fracking:
Is the reason for the dramatic increase of earthquakes in Oklahoma and Kansas between 2008 and 2016
What can be done to improve the seismic safety of the structural feature from question 1?
'Bolt and brace' the weak wall by reinforcing with boards of plywood and specialized connector brackets
Fill in the missing words in the correct order to complete the process for generating earthquake alerts as illustrated in the image shown below. earthquake nucleates pwave arrival times blank , for any use location
1. underground 2. location 3. Alert generated
About every 100-220 years, there will be a large earthquake that occurs on the Hayward fault. When was the last big one?
1868
In the next 30 years, what's the chance of an M6.7 or larger earthquake occurring on the Hayward Fault or Rodgers Creek Fault?
About 1 in 3
What is the basic equation determining slip deficit?
Tectonic motion - creep = slip deficit
What is the risk of harm in an earthquake for people inside a building with a rating of IV? (read the answer choices carefully before making your selection; the differences are subtle)
The risk to human life is small, and the structural safety is fair. Any structural and non-structural damage incurred by major shaking carries a minor threat to human life.
What is the metric of Peak Ground Acceleration (PGA) used to describe?
The strength of shaking
What five parameters of a wave were discussed in lecture? Density, Amplitude, Seismicity, Wavelength, Propagation Amplitude, Wavelength, Velocity, Frequency, Period Power, Speed, Temperature, Elasticity, Mass
Amplitude, Wavelength, Velocity, Frequency, Period
We can use hotspot volcanism as a measuring tool for plate tectonics. Mantle plumes are deeply rooted structures that originate at the boundary of the mantle and Earth's core. They are essentially stationary with time. Tectonic plates, as we know, are always moving. When a tectonic plate moves over a plume, a trail of volcanos marks its passage. By age-dating the rocks of volcanoes in a hotspot track, one can back-track how fast the tectonic plate is moving. The island of Kauai is about 5 million years old. It is located 520 km from Kilauea, which is currently active and sitting atop the mantle plume. If the rate of plate motion has been constant, how fast has it been moving? Answer in km/million years.
105 with margin: 0
What earthquake is responsible for California's worst tsunami disaster?
1964 Alaska EQ (Magnitude 9.2)
How long ago did Pangea split? 3 billion years ago 2 million years ago 200 million yrs ago 30 million years ago
200 million yrs ago
A seismometer records the following seismogram. The first wave arrives 6 seconds earlier than the second wave. If the first wave travels at 6 km/s and the second wave travels at 3 km/s, how many km away must the earthquake source be? Remember that distance = rate * time Assume that the earthquake source released both waves simultaneously. The start time on this seismogram (time = 0) is arbitrary and unrelated to the earthquake start time.
36 if distance = rate * time and the distance must be the same for how far the first and second waves have travelled, then rate1×time1=distance=rate2×(time2)rate1×time1=distance=rate2×(time2) You know rate1 and rate2. You know that time2 must be equal to time1 + a 6 second delay. set rate*time = rate*time to find time1 then compute either rate*time to find the distance.
How long was the rupture associated with the 1906 San Francisco earthquake? Correct Answer 450 km, from the South Bay to the Mendocino triple junction. 500 meters, just the length of the Golden Gate Bridge. 50 km, just across San Francisco. 600 km, from Los Angeles to San Francisco.
450 km, from the South Bay to the Mendocino triple junction.
What, approximately, is the rate of motion of the North American plate relative to the Pacific plate? 50 cm/year 5 cm/year We can't measure it as most of the boundary corresponds to the bottom of the ocean. 5 mm/year
5 cm/year
By about what percentage could earthquake early warning prevent injuries if everyone received a few seconds warning in order to drop, take cover, and hold on before an earthquake?
50%
In the California 2016 survey asking voters whether they support building an earthquake early warning system, about what percentage said they supported?
80%
What caused most of the damage related to the 1906 San Francisco earthquake? Correct Answer A fire. There was a storm, unrelated to the Earthquake that struck San Francisco. Unlucky. The earthquake itself, the shaking was very strong due to local amplifications. The aftershocks, which destroyed the building that had been fragilized by the main shock.
A fire.
Why are seismologists interested in the possibility of the Hayward fault and the Rodgers Creek fault being connected?
A longer continuous fault line increases the maximum magnitude earthquake that could be produced
What is a beheaded channel?
A remnant riverbed that has been cut off from its source where it cross the fault and is moved laterally with time
How many people are currently still living in temporary shelters due to the Spitak earthquake in 1988?
About 3,000 people.
How much more energy is released by a magnitude 5.0 earthquake, compared to a magnitude 4.0 earthquake? The same amount of energy is released by the M5.0 compared to the M4.0 About 3000 times more energy is released by the M5.0, compared to the M4.0 Twice as much energy is released by the M5.0 compared to the M4.0 The half as much energy is released by the M5.0 compared to the M4.0 About 30 times more energy is released by the M5.0, compared to the M4.0
About 30 times more energy is released by the M5.0, compared to the M4.0
Match the following names to their studies or discoveries. Alfred Wegener Continental Drift Frederick Vine and Drummond Matthews Magnetic anomalies over ocean ridges Andrew Lawson First identified the San Andreas Fault
Alfred Wegener Continental Drift Frederick Vine and Drummond Matthews Magnetic anomalies over ocean ridges Andrew Lawson First identified the San Andreas Fault
What are some measures of how big an earthquake is? The length of the rupture on the fault The economic cost of the earthquake The amount of energy released by an earthquake Size of the area the earthquake was felt The number of fatalities or injuries resulting from the earthquake All of these
All of these
What potential hazards could accompany a large earthquake on the Hayward fault?
All of these Liquefaction Fire Aftershocks Landslides
Which of these observations can be explained by plate tectonics? All of these are observations explained by plate tectonics. Ridges and trenches in the bathymetry maps. The global distribution of earthquakes Part of the fossil distribution that is similar across multiple continents.
All of these are observations explained by plate tectonics.
What are the causes of volcanic earthquakes? All of these, and possibly more! Hot magma rising and expanding, causing ruptures due to thermal expansion The turbulent flow of magma causing tremor Bubbles in the magma forming and bursting
All of these, and possibly more!
What types of plate boundaries do we have on the west coast of North America? Transform & Divergent Transform & Convergent Convergent only Transform only All three Divergent only
All three
Elastic Rebound Theory says that ____________. An earthquake is caused by the sudden release of strain in rocks that has been steadily increasing over a long period of time. Aftershocks are caused by the ground trying to move back to where it was before the initial earthquake. Most earthquake legislation comes immediately after a damaging earthquake because people become hyper-sensitive to them. After an earthquake happens, the probability of another earthquake happening in the same place after a short period of time dramatically increases.
An earthquake is caused by the sudden release of strain in rocks that has been steadily increasing over a long period of time.
The longer a fault accumulates slip deficit... (select 2 answers)
An increasingly large earthquake (or combination of earthquakes) is required to release the built up stress An earthquake of a given magnitude becomes increasingly likely
What is the name of the Berkeley professor who, with his team, wrote a report on the San Francisco earthquake in 1906 in order to scientifically explain the causes of this natural disaster? Andrew Lawson Richard Allen Ernest Lawrence George Hearst
Andrew Lawson
The Mercalli Intensity scale is a subjective scale, that is a measure of [ Select ] ["energy released", "shaking at a location"] , and is [ Select ] ["dependent on", "independent of"] distance between a location and the epicenter of an earthquake.
Answer 1:subjective Answer 2:shaking at a location Answer 3:dependent on
Since 1971, what has now become impossible to do?
Build a building on an active fault.
What's the 'reference frame problem' with trying to record earthquakes? (from lecture 4.2) Any instrument we could want to use to record the earth moving will itself also move with the shaking motion. We're looking top-down at a motion that is originating bottom-up earthquakes occur in three dimensions but standing on the surface of the earth means we only have access to two earthquakes occur deep in the earth and by the time the seismic waves reach the surface, some of the information in them is jumbled.
Any instrument we could want to use to record the earth moving will itself also move with the shaking motion.
How many faults are believed to have ruptured during the Christchurch earthquake?
Around 20 or 22.
The following graph provides evidence for what?
As water pressure goes up, earthquake frequency goes up.
When an earthquake begins , the [ Select ] ["p-wave", "Rayleigh wave", "Love Wave", "s-wave"] travels the fastest away from the source and gets detected by [ Select ] ["seismometers", "satellites", "GPS stations"] . This seismic data [ Select ] ["gets sent to the MyShake app", "gets sent to a central computer server", "gets sent to a scientist"] , which/who rapidly computes that an earthquake has begun, and estimates the magnitude, the location of the epicenter, and the area that will experience shaking - then creates a warning. The early warning system in the US requires [ Select ] ["four", "one", "ten"] stations to send data in order to confirm that an earthquake is in progress, and the system must estimate the earthquake is [ Select ] ["at least a M3", "at least a M6.7", "at least a M4.5"] in order to release a warning to the public. Delivery mechanisms like [ Select ] ["the USGS website", "MyShake", "Twitter"] deliver the warning to users. The concept of early warning is that the detection and alerting process is very fast while the [ Select ] ["damaging surface rupture", "heavy shaking that comes with the s-wave", "light shaking that comes with the p-wave"] takes time to spread away from the source. How much warning time will users get? Warning time depends on [ Select ] ["proximity to seismometers", "proximity to dense population centers", "proximity to the earthquake source"] . The closer a person is to the source, [ Select ] ["the more warning time they are able to receive", "the less warning time they are able to receive"] . You can receive an early warning [ Select ] ["only during", "before, simultaneous with, or after", "only after", "only before"] you start to feel heavy shaking.
Begins p-wave sesimometers gets sent to a central computer server four at least at M4.5 myshake heavy shaking that comes with the s-wave proximity to the eq source the less warning time they are able to receive before, simultaneous with, or after
Name the two classes of seismic waves. Head and Shoulder waves Elastic Rebound waves and Hart waves Body waves and Surface waves
Body waves and Surface waves
The Pacific plate has a relative motion of 50 mm/year with regards to the North American Plate. How is this motion accommodated on the faults? We observe faults on the East Coast of the United States that are associated with the Pacific/North American plate boundary. The San Andreas fault only accommodates for all this motion. Correct Answer California as a whole is tearing apart, all the way to Nevada in order to accommodate the plate motion. The San Andreas Fault system (which also includes the Hayward fault, Calaveras fault etc etc...) accommodates for the motion in a difuse zone of about 80 kilometers from the plate boundary itself.
California as a whole is tearing apart, all the way to Nevada in order to accommodate the plate motion
Which part of California appears to have the lowest seismic hazard?
Central Valley
When you add or extract something from the earth's crust you:
Change the stress field Can cause earthquakes
Both Alaska and Chile are on subduction zones that can experience M9+ earthquakes. Where is the earthquake risk greater?
Chile
Where was the earthquake that is responsible for causing the May 23, 1960 Tsunami on the island of Hawaii? What height was the largest wave from the low tide level?
Chile, magnitude 9.5. Height of largest wave was 14 ft
In addition to being an earthquake early warning platform for private citizens, what other function does MyShake serve?
Citizen Science Project
How are faults and plate tectonics connected? Match the correct relationship: Divergent Normal Faulting Convergent Reverse Faulting Transform Strike-Slip
Divergent Normal Faulting Convergent Reverse Faulting Transform Strike-Slip
What action should you take during an earthquake if you are inside?
Drop, cover, and hold on
Select the 3 campus buildings on this list who have Very Poor seismic safety ratings.
Evans Hall Durant Hall Moffitt Undergraduate Library
You're in class when everything suddenly rattles. It only lasts a couple of seconds and causes no damage, but it's enough to make everyone feel a little nervous. Someone does some quick Googling to find that it was a small earthquake not too far away. Someone else says 'Well, at least that little earthquake released some energy, so it's diffusing the Big One' Is this statement correct? Pick the most accurate response. Correct! Even though that small earthquake released some energy, the magnitude scale is exponential, so it would actually take many many many earthquakes of that size to even make a dent in how much energy is building for the Big One Actually, the occurrence of small earthquakes is completely independent of the stress contributing to a future Big One. One doesn't affect the other at all. actually, small earthquakes only occur on creeping faults, so their occurrence doesn't really affect the size of a big earthquake building on a locked fault That's right! Little earthquakes do help lower the risk of a Big One by using up some of the stored seismic energy Actually, small earthquakes are how the big ones build up their energy. So all the small earthquakes that occur are just going to make the Big One bigger.
Even though that small earthquake released some energy, the magnitude scale is exponential, so it would actually take many many many earthquakes of that size to even make a dent in how much energy is building for the Big One
What commonly causes the majority of injuries during an earthquake?
Falling objects
In the United States, what is one of the major causes of injury during an earthquake?
Falling objects and broken glass
Coseismic slip (during an earthquake) is the only way that faults can release their accumulating the stress. True False
False
Earthquake Forecasting and Prediction are the same thing.
False
Earthquakes occur randomly and evenly distributed on the surface of the Earth, without any clear pattern. True False
False
It is currently possible to make all the observations necessary to make earthquake prediction a reliable reality.
False
It is easy for scientists to communicate on their science
False
It is possible to reduce the hazard.
False
It is scientifically possible to make useful and believable earthquake predictions.
False
Seismologists are able to predict when an earthquake will occur but only if it is above a 6.0 magnitude earthquake.
False
Sound waves travel faster through the air than through solids. True False sound waves travel at the same speed regardless of medium
False
This picture is taken from a disaster film that talks about earthquakes.
False This picture was taken after the Loma Prieta earthquake.
While utilizing Seismic Tomography techniques, how might hotter materials affect seismic wave readings? Waves will be recorded at stations as having been sped up due to waves having the property of traveling faster through liquids Heat can cause rock to soften and thus slow down seismic wave velocities The heat of a magma plume for example, causes iron to accumulate and thus increase wave speed through the denser material
Heat can cause rock to soften and thus slow down seismic wave velocities
Seismic waves travel faster in cold materials and slower in hot materials. Cold materials are more dense, and hot materials are less dense. How, then, do seismic wave speeds relate to density of the medium? Seismic waves travel faster in MORE dense mediums Seismic waves travel faster in LESS dense medium Seismic waves speeds are not affected by density
IDKK
What is the difference between wave energy motion and particle motion? (pay careful attention to the small differences between these answers) wave energy radiates away from the epicenter and can travel great distances, whereas particle motion is how an individual bit of earth wiggles in place as earthquake energy passes through it wave energy motion describes how individual pieces of the earth travel great distances away from the epicenter, whereas particle motion describes how the force of the earthquake is distributed in a given place particles radiate away from the epicenter and can travel great distances whereas wave energy moves in place as particles pass through a given bit of earth particle motion is how individual grains of earth are propagated along the surface of the earth whereas wave energy moves through the body of the earth wave energy moves along the surface of the earth whereas particles propagate through earth's interior away from an earthquake's epicenter
IDKK
Love waves move side to side like a snake, but with the largest motion towards the surface of the earth side to side like a snake up and down like a bouncy ball in a roll-back motion in a roll-back motion, but with the largest motion towards the surface of the earth like a slinky compressing and expanding like a slinky compressing and expanding, but with the largest motions towards the deep earth Love waves are not a real type of seismic wave
IDKKK
In lecture, Professor Rademacher talked about attempts to predict earthquakes in China using foreshocks. In 1975, Chinese scientists used a swarm of small earthquakes to predict that a significant earthquake was imminent and Haicheng was evacuated just hours before destructive shaking occurred. What happened in 1976?
In August 1976 an imminent earthquake was predicted and an evacuation was ordered. People sept in tents for nearly 2 months and no earthquake occurred. In July 1976 there were no immediate precursors and no evacuation was ordered. More than 250,000 people died and it was one of the deadliest earthquakes.
What makes of Taiwan a particularly active seismic area?
It is a double subduction zone
What is the Ring of Fire? It is a geographical area located all around the Pacific ocean, where volcanoes and very strong earthquakes are co-located. The deepest trench in the world, whose depth is, in absolute value, greater than the Mount Everest is tall. It corresponds to all the regions in the world where we can find oil and gas. All the volcanoes that we can find in the Mid-Oceanic ridge.
It is a geographical area located all around the Pacific ocean, where volcanoes and very strong earthquakes are co-located.
How did the San Andreas fault form? We don't yet know how the San Andreas fault was formed. It was originally a rift zone which became inactive and was easily fractured along the old rift ridge. It was originally a subducting plate that fully subducted and the Pacific Plate movement took over. It was originally a continent-continent convergent plate boundary, until the North American plate change direction causing it to turn to transform faulting.
It was originally a subducting plate that fully subducted and the Pacific Plate movement took over.
How did Founder's Rock get to its current location?
It was transported to it's current location by the west side of the fault carrying it along
For both the Tohoku'oki earthquake in Japan and the Sumatra earthquake, 300,000 people were threatened by a tsunami. However, 230,000 people died from the Sumatra tsunami while 16,000 died in Japan. What made the difference?
Japan put in effort to reduce its population's vulnerability
Which of the following can be found using local tomography? Oil and gas sources Mineral composition Diamond mines
Oil and gas sources
What region of the US was not seismically active in 1996 but became extremely active in the last decade?
Oklahoma and Texas
What can seismograms tell you? (Select 2) The amount of a mineral in the Earth's crust Location of the Earthquake Reveal information regarding the structure of the Earth's interior How earthquakes react to T waves When a volcano will erupt
Location of the Earthquake Reveal information regarding the structure of the Earth's interior
Read the following description of energy released by the 2004 Northern Sumatra Earthquake from the USGS website. Is what they are describing related to the magnitude or the intensity or something else? The 2004 Sumatra earthquake released an estimated "20×101720×1017Joules, or 475,000 kilotons (475 megatons) of TNT, or the equivalent of 23,000 Nagasaki bombs [worth of energy]." Frequency content Correct! Magnitude Seismic wavelength Intensity the power of the accompanying volcanic eruption
Magnitude
To receive early warnings in CA, (and get other global earthquake information) what app should you (pretty please) download?
MyShake
Did the event they describe in their tweet actually happen? (Hint: Check this USGS earthquakes page (Links to an external site.), where I have already narrowed some search parameters for you (you can view them by clicking the gear icon in the upper right corner))
No
Your company is summoning you to move to Perm in almost-Siberia, Russia for work. Should you be worried about seismic activity there? (N.B.: Of course the correct answer would be to just resign. Nobody should be forced to go work in Perm.) (N.B. 2: Perm is actually located on a cool geologic anomaly, where we observe slow seismic velocities using tomography, without completely understanding what is causing this anomaly.) (N.B. 3: Perm has also the last Gulag Soviet corrective labor colony (Perm-36) still standing in Russia, turned into a museum. Read Solzhenitsyn for more information. If not enough time for the Gulag Archipelago, you can watch this video (Links to an external site.).)
No
Which of these faults are most commonly responsible for the formation of tsunamis?
Normal fault Thrust fault
When should you turn off your gas after an earthquake? See https://www.ready.gov/safety-skills (Links to an external site.) for a recap
Only turn off the gas if you smell gas after an earthquake
What statements are true regarding faults: (select all that apply) Out of all the different types of faulting, oblique is the most common. They release stress during an earthquake They accumulate mechanical stress from tectonic environments There are six different types of faulting movements The boundary between two plates is made of them
Out of all the different types of faulting, oblique is the most common. They release stress during an earthquake They accumulate mechanical stress from tectonic environments
Over the last 100 years, how many people have succumbed to earthquake related disasters?
Over 2 million people
What do we call the science that looks at geologic sediments and rocks, for signs of ancient earthquakes?
Paleoseismology
What disciplines are brought together for the preparedness campaign?
Physical science, emergency management and communication.
Our current understanding of how the surface of the earth moves is called _____________. Plate Tectonics Theory Tectonic Drift Theory Continental Drift Theory Magnetic Reversal Theory
Plate Tectonics Theory
Pick 4 sources of vulnerability related to earthquakes and associated hazards.
Poorly built buildings dense populations living where serious earthquakes can occur brittle water pipes limited transportation routes in and out of an earthquake-prone region
Identify what this statement is an example of: 'There will be a M6.2 earthquake in Arcata, CA, on May 3rd, 2022'
Prediction
Identify what this statement is an example of: 'There will be a M6-7 earthquake in Oaxaca, Mexico the next time the moon is full.'
Prediction
What is the difference between predictions and forecasts?
Predictions are certain because the laws of the given process are understood. Forecasts involve probability because the laws that govern a process are not understood
What adaptation did they do to the pipeline in Alaska where it crosses the Denali fault? Put the pipeline on gliders to let the stiff pipe move side to side. Put it on stilts. Made the pipeline out of more flexible material so it can bend. Buried it under the ground
Put the pipeline on gliders to let the stiff pipe move side to side.
What are the elements that describe a fault? Coordinates, Rake, Dip Rake, Strike and Dip Coordinates and Dip Direction Strike, Location and Altitude
Rake, Strike and Dip
What does a probabilistic ground shaking model like this one depict?
Regions with a set probability of exceeding a certain intensity of earthquake shaking in a given timeframe
Select all the different types of faults mentioned in class: Reverse/Thrust Northing Normal Perpendicular Oblique Strike Slip
Reverse/Thrust Normal Oblique Strike Slip
What are the two different types of strike-slip faulting? Right Lateral and Left Lateral Reverse and Thrust Divergent and Convergent Foot Wall and Hanging Wall
Right Lateral and Left Lateral
What instrument is used to measure seismic waves and which principle is it based off? Seismograph, principle of friction Seismogram, principle of friction Seismogram, principle of inertia Seismograph, principle of inertia
Seismograph, principle of inertia
Which of the following statements are true about sound waves? Sound waves travel faster through air than water. Sound wave speed decreases with higher temperature.. Sound waves can transport information and energy from a source to a receiver. Sound waves cannot travel through objects denser than water.
Sound waves can transport information and energy from a source to a receiver.
What is necessary for Elastic wave propagation? Time and temperature S and Body waves Source and medium
Source and medium
What are some of the key measurements/research concepts that go into the development of an earthquake forecast?
Study of earthquake rupture history for a given fault State of stress on a given fault Rate of tectonic motion Rate of creep on faults
What is an Earthquake early warning system?
System of several seismic stations that detect nearby earthquakes and conduct rapid calculations in order to warn people further out before they are affected by the shaking of an earthquake.
What properties of a medium affect sound speed? Temperature and density Density and seismicity Direction of wave propagation The amount of empty space in the medium
Temperature and density
Is the Hayward fault locked or creeping?
The Hayward fault is hybrid: creeping in some sections and locked in others (especially at depth)
Which of these best describes the definition of magnitude? how widely felt the earthquake was the height of the seismic waves The strength of shaking felt on the surface in a particular place Correct! The amount of energy released by an earthquake
The amount of energy released by an earthquake
Which definition better describes the dip angle: The angle between a horizontal line and the face of the surface The angle along which the fault slips The angle between a vertical line and the face of the surface Dip angle is always 35 degrees
The angle between a horizontal line and the face of the surface
The safety of the Hearst Memorial Mining Building was improved using 'base isolators'. What is this and what does it do?
The building is supported by pillars with rubber bearings that allow the ground to move underneath the building without transferring much of the shaking up into the structure itself.
This is a 3D slice of South America. The top curve represents the surface of the continent. The sideview is a tomographic image of the earth at depth beneath. The Nazca tectonic plate is moving towards and subducting under the South American plate. The tomographic image features a blue-violet-white oblong blob that starts at the top at South America's western coast and crosses diagonally eastward with depth. What is this blob? Cooler colors (blue purple white) are for faster seismic wave speeds, and warmer colors (yellow red) are for slower velocities. Green is where the velocities match the overall average. The portion of the Nazca plate, which is COLDER than the surrounding mantle, which has subducted under the continent and is plunging towards the core. The portion of the Nazca plate, which is HOTTER than the surrounding mantle, which has subducted under the continent and is plunging towards the core. The COLD root of the South American continent The HOT root of the South American continent
The portion of the Nazca plate, which is COLDER than the surrounding mantle, which has subducted under the continent and is plunging towards the core.
Which of these best describes intensity? The amount of energy released by an earthquake The height of the seismic waves Correct! The strength of earthquake shaking in a particular location The stress difference on the fault before and after an earthquake
The strength of earthquake shaking in a particular location
In the most recent seismic safety assessment of campus buildings, McCone Hall (which houses the Earth and Planetary Science department, including the Berkeley Seismology Lab) was given a rating of V. What does this mean?
The structure quality is poor
Dr. Lori Dengler explains the localized Crescent City tsunami caused by the magnitude 8.4 Kuril Islands earthquake. Why was this event so notable for her team?
The tsunami highlighted the dangers of strong currents and the importance of implementing localized tsunami advisories.
What best describes the cause of the Fukushima Daiichi nuclear disaster?
The tsunami wave caused by the 2011 Japan earthquake destroyed the sea wall protecting the power plant and engulfed the diesel engines, shutting down the primary and secondary cooling systems and melting the plant's reactor blocks.
What did Voltaire argue about in his poem (Poem on the Lisbon Disaster) and later, in his novel Candide?
The very idea of this earthquake and disaster happening in Lisbon was contrary to the idea that we live in the best of all possible worlds, which serves only to demean humanity and ultimately lead to fatalism.
This absolute gem of an email (including the screenshots) was sent to members of the Berkeley Seismology Lab on July 20th, 2020: GREETINGS: I know your field is a scientific investigation of seismology. But history involves a mystery that has to solved. The Lincoln assassination & the S.S. Titanic striking an iceberg both occurred on April 14th between 10 PM---12 Midnight EXACTLY 47 years apart to the day. Lincoln & the S.S. Titanic both met their fates on APRIL 15 ( 4/15 ). Lincoln breathed his last & the Titanic sank beneath the waves of the Atlantic. It might be a code of some sort as the Tel. Area Code for San Francisco, CA is "415". Oh by the way, the photo attachment of the gold medal is an authentic medal made in 1912. It is extremely rare & I found it on person at my condo at [address redacted for privacy] in 2017 only after my Lyme disease specialist doctor moved in 2015 to [address redacted for privacy]. I believe these historical facts and other information leads me to the conclusion that these are elements forming a pattern of destiny. Now, there is no 100% absolute guarantee that this minor EARTHQUAKE mentioned above is going to occur in San Francisco, CA on schedule. BUT IF IT DOES, there will definitely be several other accurate predictable QUAKES that will culminate in the "BIG ONE" on the World famous San Andreas Fault in California on GOOD FRIDAY, APRIL 2, 2021. Based on the text of their email and the tweets in the screenshots, what two things does this person think is going to happen?
There will be an earthquake along the San Andreas Fault on Good Friday, April 2, 2021. There will be an earthquake on July 22nd 2020.
Why is or why isn't their logic credible?
These instances have no correlation to earthquakes. They cant predict nor forecast an earthquake.
This is a building at Residence Hall Unit 1. What are the X-shaped features, and what is their function?
They are cross braces which provide strength when the building experiences shear stress from shaking
Why are women twice more likely to be injured during an earthquake on the West Coast or in New-Zealand?
They are more likely to be looking after children and hence will be moving to find them before ensuring their own safety.
What is one reason that volcanic earthquakes are important? They aren't important They are caused by exactly the same physical processes as tectonic earthquakes They may be used to forecast eruptions
They may be used to forecast eruptions
How did engineers mitigate the risk in the Claremont water pipeline?
They put another pipe in the pipe that would ensure the water to keep flowing even in the event of an earthquake.
What does it mean that earthquake rupture is a 'critical failure process', and what does that say about the earthquake prediction problem? (Critical failure process meaning a large build up with a resulting "break" point... like filling up a water balloon slowly and it hits a point of total failure and "pops".)
This is when an earthquake builds up continuously and ends rupturing with an enormous rupture at a later time. This creates problems with earthquakes as its already nearly impossible to predict earthquakes.
In the last 100 years, over half of the total energy released by earthquakes came from Three earthquakes, with magnitudes greater that 9 .
Three earthquakes, with magnitudes greater that 9
What type of faulting is observable in the southern island of New-Zealand?
Transform fault
Match the plate boundary to the natural hazards and observations commonly associated with them. Transform plate boundary There are generally no volcanoes, but there is shallow seismicity. Divergent plate boundary There are volcanoes and also shallow-moderate seismicity. Convergent plate boundary There are often explosive volcanoes and wide range of seismicity (shallow to deep).
Transform plate boundary There are generally no volcanoes, but there is shallow seismicity. Divergent plate boundary There are volcanoes and also shallow-moderate seismicity. Convergent plate boundary There are often explosive volcanoes and wide range of seismicity (shallow to deep).
Being able to see building collapse on seismic records helps us better understand the process and in turn, make buildings safer.
True
Rayleigh waves are a type of surface wave. True False this is not a real type of seismic wave
True
UC Berkeley is deploying major efforts (and money) to mitigate the risk on the campus' buildings.
True
To be a valid earthquake prediction, what three components must be answered?
Useful predictions need to tell you when, where, and how strong an earthquake will be.
What is the name of the narrow, deep zones where intermediate to deep earthquakes happen? Wadati-Benioff zones A trench We don't have any name for it as there is no preferred pattern for earthquakes location. All earthquakes occur at the same depth, which is 10km.
Wadati-Benioff zones
Which of the following is NOT a strategy used to reduce seismic risk?
Wait-and-see policy, the government will take actions anyways
Why did earthquakes in Oklahoma go from 1-3 per year to hundreds per year starting around 2008?
Wastewater injection was unregulated and high pressured in Oklahoma
Why is the hazards map of the United States showing increase in hazards for Northern Texas, Oklahoma, and Kansas area over the past 20 years?
We have been observing more earthquakes in these areas
What is a hazard?
What nature presents to us, on which humans have no influence.
What is vulnerability?
What we put in nature's way to reduce the potential damages.
What is liquefaction?
When wet, loose sediments are shaken, the water is squeezed up to the surface and makes it unstable, like wet jelly
Earlier this year, a series of events led scientists to predict that a volcanic eruption was imminent in Iceland. What was the evidence that supported this prediction? First there was [ Select ] ["a magnitude 5.7 earthquake", "a small eruption near the southern coast of the Reykjanes peninsula", "a magnitude 7.2 earthquake", "a magnitude 9 earthquake", "many recordings of volcanic tremor"] , which marked a major departure from the background activity. Following this there was [ Select ] ["almost continuous seismic activity", "suspiciously low amounts of seismic activity, which suggested the aftershocks were being absorbed by magma", "a series of discrete tremors to the south", "a small handful of other largish aftershocks"] , which [ Select ] ["marched steadily towards the southwest", "marched steadily towards the northeast", "became progressively shallower", "grew in magnitude", "grew progressively deeper", "shrank in magnitude"] as the days passed. Simultaneously, satellite measurements found that the area under the Fagradalsfjall volcano had [ Select ] ["deflated by over 10 cm", "inflated by over 10 cm", "started releasing huge gushes of steam", "gone suspiciously quiet", "started degassing large amounts of toxic volcanic gasses", "started to open in a series of cracks and fissures"] . All this led scientists to understand that [ Select ] ["magma was rising and moving under the surface", "volcanic activity was slowly subsiding", "a lot of stress was building up on nearby faults", "the magma under Fagradalsfjall had gotten suddenly hotter", "a new volcano was being formed just off the coast"] , which soon [ Select ] ["did erupt in spectacular fashion and swallowed up the volcano observatory perched on the rim", "did erupt in spectacular fashion, causing damage to the local airport", "did erupt in spectacular fashion, but caused no damage because of the volcano's remote location", "ended up fizzling out into dormancy for the next 800 years", "resulted in a big steamy eruption as magma burst through the sea floor underwater"] .
a magnitude 5.7 earthquake almost continuous seismic activity marched steadily towards the northeast inflated by over 10 cm magma was rising and moving under the surface did erupt in spectacular fashion, but caused no damage because of the volcano's remote location
Pick the best explanation to justify your answer to the question about whether earthquake risk is greater in Alaska or Chile: ---Some facts about each place--- Population: Alaska: 730,000 people Chile: 18,700,000 people Area: Alaska: 660,000 sq mi (1,720,000 sq km) Chile: 290,000 sq mi (760,000 sq km) Number of volcanoes (active in the last ~10,000 years): Alaska: 80 Chile: 105
although the hazard is the same (both can experience M9 earthquakes), Chile has a larger population exposed to the hazard, so the risk there is greater
The New Madrid Seismic Zone is thought to have been: an old rift zone an old hot spot an old transform plate boundary an old subduction zone
an old rift zone
What did Japan do to reduce its vulnerability to tsunami hazard? select 3 correct answers.
build seawalls and other ocean barriers implemented a tsunami warning system educated its citizens on what to do if a tsunami is coming
What are some visible signs in the facade of the stadium that are evidence of fault-related strain? (select 3)
centimeters of offset in the blocks that make up the north entrance archway cracking in the stairs as they are yanked on by the creeping fault diagonal cracks resulting from shearing forces
P waves are compressive waves shear waves surface waves retrograde waves not a real type of seismic wave
compressive waves
What is the most common way to dispose of fracking wastewater?
disposal at depth
This map of the US depicts areas that have a 2% chance of experiencing earthquake shaking in the next 50 years. The warm colors (orange and red) are where heavy shaking could occur. The cool colors (blue and grey) are where light shaking could occur. What two answers are a true statement about this map?
earthquake hazard exists anywhere there is color there is an equal risk of light shaking in Texas as there is of heavy shaking in California
In the last 20 years, only 4 people have died as a result of an earthquake. However, the HayWired Scenario suggests that a major earthquake under an urban center could result in 800 deaths. This means that a single earthquake could result in more deaths than the last 10 deadliest wildfires combined. What does this indicate about earthquake risk in California?
earthquake risk in California is greater than recent history alone would suggest earthquake risk in California might actually be greater than wildfire risk
Why is an explosion that looks to be equivalent to a 3.2M earthquake on a seismometer for intense and destructive than an earthquake of similar magnitude?
earthquakes are contained underground and lose energy as it travels through the earth's crust, where as explosions release all of their energy into the air and immediately surrounding spaces only a small amount of energy goes into the ground so the seismic reading of 3.2M is only capturing a portion of the actual energy expelled
Select the best 3 strategies for reducing earthquake vulnerability.
educate citizens on what to do during, before, and after an earthquake create redundant systems so that if one fails, you can use the other (like using radio to communicate if cell towers go down) create a local plan for how to handle earthquakes
Earthquakes in Seattle and San Francisco are caused by the same tectonic mechanisms. True False
false
Fill in the blanks to correctly complete this statement. The ground can shake with an earthquake for many reasons. In the case of tectonic earthquakes, the shaking is caused by [ Select ] ["volcanoes growing along tectonic boundaries", "faults rupturing due to bubbles and currents along the underside of the tectonic plates", "faults rupturing as a result of accumulated tectonic stress", "rocks breaking under the weight of the continents"] . This comes in three main varieties, normal, reverse, and strike-slip faulting . In the case of volcanic earthquakes, [ Select ] ["rising magma pushing through the crust", "superheated mudslides on the volcano's flanks", "bubbles in the magma", "mantle convection beneath the volcano"] can cause rock structures to crack and break, the flow of superheated water or magma through the subsurface can cause volcanic tremors, and the convective mantle flow that powers hotspot plumes can be registered as rumbles by a seismometer.
faults rupturing as a result of accumulated tectonic stress normal, reverse, and strike-slip faulting rising magma pushing through the crust the flow of superheated water or magma through the subsurface bubbles moving and popping in magma bodies
Pick 3 sources of vulnerability related to earthquakes and associated hazards.
fragile electrical and communication systems building on a hillslope that can slide away in a landslide having lots of people who are unfamiliar with/uneducated about earthquakes move into an earthquake-prone area
Read the following excerpt from a LA Times article about the Ridgecrest earthquake, and fill in the blank: "Instruments across California recorded varying durations of the strongest shaking emanating from Ridgecrest. A device at the Naval Air Weapons Station China Lake (Links to an external site.), about a mile away from the ruptured fault, showed it lasted for a relatively short period, [USGS seismologist Robert] Graves said — perhaps 15 to 20 seconds. But that was on bedrock, said USGS seismologist Susan Hough. Shaking energy that feeds into softer sediments can increase the intensity felt at the surface and [cause the shaking to] last dramatically longer." Answer 1:Correct!intensity
intensity
What components are needed for an earthquake prediction to be useful?
interval of time when it will occur Magnitude (or narrow magnitude range) Specific location
12 people a year die while taking selfies (usually because they stop focusing on the dangerous things around them, like trains, cars, and cliffs). Roughly 10 people die a year from shark attacks. Both of these hazards are deathly. Which is associated with greater risk?
it depends on exposure to the hazard; do you surf more often, or take selfies more often?
Unconventional oil and gas differs from conventional oil and gas in which ways:
it is trapped within shale whereas conventional accumulates under cap stones
Below is a quote from the Anchorage Daily News about the 2018 M7 earthquake in Alaska. Is the quantity of energy inferred from the earthquake's magnitude or intensity? [The] earthquake just north of Anchorage on Friday morning shredded the earth with 2 million tons of explosive force, and generated 650 aftershocks within 30 hours, some of them large enough to rattle residents all over again, experts say. intensity the quantity of energy is related to neither of these concepts Correct! magnitude
magnitude
Is their logic credible?
no
Which of the following are valid and consistent precursors that can help us predict the occurrence of earthquakes? Foreshocks and seismic swarms Ground uplift and electrical conductivity None of the above. All of the above. The release of radon gas
none of the above
Strawberry Creek runs East to West, from the Berkeley hills into the Bay. It is:
offset by the Hayward fault, and a section of it runs North parallel to the fault
The Haywired scenario is:
one possible version of how a M7.0 earthquake could play out on the Hayward Fault
Select the fastest seismic wave. (disregard answers that are not real seismic waves) S-wave P-wave Tectonic wave Lawson wave Rayleigh wave Creeping wave Love wave
p-wave
How does using an inertial mass in seismometers help solve the reference frame problem? The frame/ housing of a seismometer is securely coupled to the ground, such that it moves exactly as the ground does. When the ground moves, the inertial mass suspended inside the frame moves in accordance with the motion. The seismometer can therefore measure how much the frame moves relative to the mass , since the latter effectively responds on a delay to the ground's shaking. Answer 1:securely coupled to Answer 2:exactly as Answer 3:moves in accordance with Answer 4:the frame moves relative to the mass
partial
In lecture 4.2 'Measuring Seismic Waves', at about 22 min, the instructor shows a seismogram of an earthquake that occurred in eastern Russia and was recorded in Berkeley. The recording is nearly an hour long. However, a seismometer in Kamchatka, near where the epicenter was, would have recorded the earthquake with a much shorter duration. Why? Fill in the blanks so that the explanation below correctly answers the question. Seismic waves travel at different speeds. Near to an earthquake source, the spacing between each wave will be relatively large . As the waves travel to greater distances, the faster waves will increasingly outpace the slower ones. In Berkeley, the slower waves were delayed relative to the faster ones such that it took nearly an hour for all the shaking to come through. Answer 1:different Answer 2:relatively large Answer 3:increasingly outpace Answer 4:delayed relative to
partial
What are the primary factors that determine the severity of an earthquake hazard? 1) The [ Select ] , which is itself determined by [ Select ] and [ Select ] . 2) The [ Select ] , which is calculated using [ Select ] .
peak ground acceleration magnitude local ground materials probability of a given earthquake occurring research into historic patterns of seismicity
Propagation direction is the direction a wave travels. For example, a seismic wave must propagate from the hypocenter of an earthquake to a station in order for the station to record it. Match each particle motion orientation to the correct wave. back and forth in the same direction as propagation P-waves backwards elliptical motions parallel to propagation direction Rayleigh waves side to side perpendicular to propagation direction Love waves perpendicular (both side-to-side and up-and-down) to propagation direction S-waves
pwaves,rayeighwaves,lovewaves,swaves
The probability of a M8 earthquake in the next 30 years in the Bay Area is substantially smaller than the probability of a M6.7. What do you think is making the difference?
smaller earthquakes are more common, and larger earthquakes are more rare
What defines 'hazard'?
something that can cause harm
In what direction are the East Bay hills moving relative to the lowlands and the Bay?
southward
What properties of earth material can affect seismic wave speeds? temperature, density, composition (such as chemical make-up) temperature, composition (such as chemical make-up), depth density, depth, composition (such as chemical make-up) scientists have no idea what controls wave speeds
temperature, density, composition (such as chemical make-up)
Why is there no correlation between wastewater injection and earthquakes in California? (select all that apply)
the amount of wastewater injection has been constant wastewater pressure is regulated
What defines 'risk'?
the likelihood of experiencing a harm
Lawson waves can travel through solids only through solids and liquids through liquids only only through the air this is not a real type of seismic wave
this is not a real type of seismic wave
Tectonic waves can travel this is not a real type of seismic wave through solids and liquids through solids only through liquids only only through the air
this is not a real type of seismic wave
P waves can travel through solids and liquids through solids only through liquids only only through the air this is not a real type of seismic wave
through solids and liquids
S-waves can travel through solids and liquids through solids only through liquids only only through the air this is not a real type of seismic wave
through solids only
The international monitoring system was implemented by CTBTO with the purpose of
tracking seismic activity related to nuclear testing tracking radioactive measurements related to nuclear testing
There is a big difference in terms of geology from one side to the other of the San Andreas fault. Correct Answer True False
true
What defines 'vulnerability'?
usceptibility to harm
Forensic seismology:
uses seismicity to help solve mysteries
Hawaii is made up of islands formed as a result of hotspot volcanism. Hawaii's oldest islands are to the west-northwest, and its youngest island is to the east-southeast. In what direction, then, must the oceanic plate be moving? east-southeast east west-southwest Correct! west-northwest east-northeast north
west-northwest
Hawaii is made up of islands formed as a result of hotspot volcanism. Hawaii's oldest islands are to the west-northwest, and its youngest island is to the east-southeast. In what direction, then, must the oceanic plate be moving? east-southeast east-northeast east west-southwest north west-northwest
west-northwest
In the last 20 years in California, there have been 2 earthquakes that resulted in loss of human life: 1) the 2003 M6.6 San Simeon earthquake, which killed 2 people and injured 40 2) the 2014 M6.0 Napa earthquake, which killed 2 people and injured 200 Meanwhile, in the last 20 years in California, 10 wildfires have each resulted in at least 6 deaths. The most deadly was the 2018 Camp Fire, which killed 85 people. Based purely on the trends of the last 20 years, which hazard is associated with the greatest fatality risk?
wildfires