Midterm Studying Flashcards
- What is the cause of the Earth’s geomagnetic field?
a.Convection of the mantle
b.Flow of the outer core
c.Solar storms
d.Radioactivity within the Earth
B. Flow of the outercore
Describe the bulk rheology and composition of the mantle asthenosphere?
a.Solid, ductile, plastic silicate rock
b.Solid, brittle, elastic silicate rock
c.Liquid silicate rock
d.Liquid iron/nickel allo
a. Solid, ductile, plastic silicate rock
The mantle asthenosphere is composed of silicate rocks that are solid but behave in a ductile, plastic manner due to high temperatures and pressures. This allows for slow, convective flow, which plays a critical role in plate tectonics and the movement of Earth’s lithospheric plates.
If current plate tectonic motions continue millions of years into the future, what is likely to happen to the continent of Africa?
a.South Africa will collide with Antarctica, forming a new continental collision zone.
b.The Indian Ocean will subduct beneath East Africa, forming a new volcanic arc.
c.East Africa will split from the main part of Africa, forming a new ocean in between.
d.North Africa will separate from Europe (Eurasia), and the Mediterranean Sea will grow into an ocea
c. East Africa will split from the main part of Africa, forming a new ocean in between.
The East African Rift is an active continental rift zone where the African Plate is slowly splitting into two parts: the Somali Plate and the Nubian Plate. If this tectonic activity continues over millions of years, East Africa will eventually break away from the rest of the continent, and a new ocean basin will form between them.
Why might Vancouver experience larger shaking intensity during a Cascadia megathrust earth-quake than Victoria, even though Vancouver is situated further from the plate boundary?
a.Because more people live in Vancouver than Victoria, so theriskis higher in Vancouver.
b.Because the earthquake hypocenter (the point on the fault where the rupture starts) is likely to lie directlybeneath Vancouver.
c.Because Vancouver lies closer to the Cascade arc volcanoes (e.g. Mt Baker) than Victoria, and the earth-quake will likely trigger volcanic activity.
d.Because much of Vancouver is built on soft sedimentary rocks which amplify ground shaking (site effects),whereas most of Victoria is built on harder bedroc
d. Because much of Vancouver is built on soft sedimentary rocks which amplify ground shaking (site effects), whereas most of Victoria is built on harder bedrock.
Vancouver is built on softer sedimentary soils, which can amplify seismic waves, increasing the shaking intensity during an earthquake. In contrast, Victoria, which is built more on hard bedrock, would experience less amplification of shaking. This difference in ground materials is a key factor in why Vancouver might experience stronger shaking than Victoria despite being farther from the plate boundary.
- When were the theories of Continental drift and Plate tectonics developed?
a.They were both developed in the 1910s.
b.Continental drift was developed in the 1910s, and Plate tectonics in the 1960s.
c.Plate tectonics was developed in the 1910s, and Continental drift in the 1960s.
d.Continental drift was developed during the Second World War, and Plate tectonics in the 1960s.e.Plate tectonics was developed during the Second World War, and Continental drift in the 1960
b. Continental drift was developed in the 1910s, and Plate tectonics in the 1960s.
The theory of Continental Drift was proposed by Alfred Wegener in the 1910s, suggesting that continents were once joined together in a supercontinent called Pangaea and have since drifted apart. The theory of Plate Tectonics emerged in the 1960s after further research, such as seafloor spreading and the mapping of global earthquake zones, provided the mechanism for how continents move.
Approximately how much more seismic moment (“energy”) is released in aMw6.0 earthquakethan aMw5.0 earthquake?
a.6/5 = 1.2 times as much
b.106/105= 10 times as much
c.(106/105)1.5 =∼32 times as much
d.(106/105)10 = 100 times as much2
The correct answer is:
c.(106/105)1.5 =∼32 times as much
The moment magnitude scale (Mw) is logarithmic, meaning that each whole number increase on the scale corresponds to a release of about 31.6 times more energy (or approximately 32 times). Therefore, a Mw 6.0 earthquake releases significantly more energy than a Mw 5.0 earthquake.
- What occurs during planetary differentiation?
a.Smaller planetesimals collide to form a larger planetary bodies.
b.A meteorite bombardment adds new material to the planet.
c.The planet melts and separates into an iron-rich core and silica-rich mantle.
d.Gas condenses to dust particles, which in turn aggregate to larger grains and roc
The correct answer is:
c. The planet melts and separates into an iron-rich core and silica-rich mantle.
During planetary differentiation, a planet or planetary body undergoes melting due to heat generated from various sources (such as radioactive decay and impacts). As it melts, denser materials, like iron, sink to form a core, while lighter materials, like silicates, rise to form the mantle and crust. This process leads to the formation of distinct layers within the planet.
- Which best describes the relationship betweenstressandstrain?
a.Strain causes stress.
b.Stress causes strain.
c.Stress and strain describe the same thing.
d.Stress and strain are mutually exclusive
The correct answer is:
b. Stress causes strain.
In the context of geology and materials science, stress refers to the force applied to a material, while strain is the deformation that results from that stress. When stress is applied to a material, it deforms, which is the strain. Thus, stress leads to strain, not the other way around.
- The main mechanism for heat transfer through the mantle mesosphere and asthenosphere is:
a.convection.
b.conduction.
c.radiation.
d.all of the above contribute to heat transfer, in roughly equal proportion
The correct answer is:
a. convection.
The main mechanism for heat transfer through the mantle mesosphere and asthenosphere is convection. In these regions, the material is solid but can flow slowly, allowing heat to be transferred through the movement of the mantle material. While conduction does occur, convection is the dominant process due to the high temperatures and pressures involved. Radiation is negligible in these contexts.
- If the BC government built an earthquake early warning system on Vancouver Island, what would happen to the seismichazard and seismicriskin Victoria?
a.The hazard would decrease, but the risk would stay the same.
b.The hazard would stay the same, but the risk would decrease.
c.Both the hazard and the risk would decrease.
d.Both the hazard and the risk would stay the same
The correct answer is:
b. The hazard would stay the same, but the risk would decrease.
The seismic hazard refers to the likelihood of an earthquake occurring in a given area, which would remain unchanged regardless of an early warning system. However, an earthquake early warning system would provide advance notice of seismic activity, allowing people to take protective actions, thus reducing the potential for injury, damage, and loss—thereby decreasing the overall seismic risk.
What is liquefaction?
a.When water is released into the mantle at subduction zones, leading to arc volcanism.
b.When mantle rocks undergo decompression melting at mid-ocean ridges, forming liquid magma.
c.When saturated sedimentary rocks liquefy during earthquake shaking.
d.When waste-water from fracking is buried at depth, increasing pore pressures and triggering induced earth-quakes.
The correct answer is:
c. When saturated sedimentary rocks liquefy during earthquake shaking.
Liquefaction occurs when saturated sediments lose their strength and behave like a liquid due to the shaking from an earthquake. This process can lead to significant ground deformation and damage to structures, as the solid ground can momentarily act like a liquid, causing buildings and other infrastructure to sink or tilt.
What is a postglacial earthquake?
a.Any earthquake that occurred during the Holocene (i.e., since the end of the last Ice Age)
b.An earthquake caused thawing of the ground surface following the melting of ice sheets and glaciers
c.An earthquake caused by shearing stresses from the flow of glaciers over the Earth surface
d.An earthquake caused by bending stresses following the melting of ice sheets and glacie
d. An earthquake caused by bending stresses following the melting of ice sheets and glaciers.
Postglacial earthquakes are typically associated with the rebound of the Earth’s crust after the weight of ice sheets and glaciers is removed due to melting. As the crust adjusts and rebounds, it can generate earthquakes due to the release of built-up stresses.
What is the earthquake epicenter?
a.The point on the fault plane where the earthquake rupture starts.
b.The point on the fault plane where the earthquake rupture stops.
c.The point on Earth’s surface immediately above where the earthquake rupture starts.
d.The center point of the ruptured fault plane.e.The point on Earth’s surface where the largest intensity was felt.3
c. The point on Earth’s surface immediately above where the earthquake rupture starts.
The epicenter is the location on the Earth’s surface that is directly above the focus (or hypocenter), where the earthquake rupture initiates. It is often used to describe the location of an earthquake in reports and maps.
What class of earthquake was the 2011Mw9.0 Tohoku (Japan) earthquake?
a.A shallow crustal earthquake
b.A subduction megathrust earthquake
c.An intermediate depth, intraslab earthquake
d.A deep earthquake
b. A subduction megathrust earthquake.
The 2011 Mw 9.0 Tohoku earthquake occurred at the boundary between the Pacific Plate and the North American Plate, where the Pacific Plate is being subducted beneath the North American Plate. This type of earthquake is characterized by a large magnitude and significant energy release, typical of megathrust earthquakes associated with subduction zones.
Why, in some arid countries, are human settlements often located along active faults?a.The water table can pond against a fault, forming springs and providing a source of water.
b.Faults form valleys, along which rivers flow, providing a source of water.
c.Earthquake shaking produces sedimentary rocks, providing better conditions for farming.
d.Faulting parallels coastlines, where people live in order to trade and fis
a. The water table can pond against a fault, forming springs and providing a source of water.
In arid regions, faults can create fractures that allow groundwater to rise to the surface, forming springs. This provides a crucial water source for human settlements, making these locations desirable even though they are situated along active faults.
What is a natural hazard?
a) A hazardous event that causes economic loss
b) A natural event that is potentially dangerous
c) A human-induced disaster
d) A method of disaster response
b) A natural event that is potentially dangerous
What distinguishes geological hazards from weather or climate hazards?
a) Geological hazards are always more deadly
b) Geological hazards are caused by processes occurring in the solid Earth
c) Weather hazards are more common than geological hazards
b) Geological hazards are caused by processes occurring in the solid Earth
Which of the following best describes a natural disaster?
a) A natural event that occurs randomly
b) A hazardous event that causes loss of life, damage, or economic losses
c) Any weather-related phenomenon
d) A geological event without any impact on humans
b) A hazardous event that causes loss of life, damage, or economic losses
What is the relationship between magnitude and frequency of hazardous events?
a) They are directly proportional
b) They are inversely proportional
c) There is no relationship
d) Frequency always increases with magnitude
b) They are inversely proportional
What does risk describe in the context of natural hazards?
a) The likelihood of a hazardous event occurring
b) The number of people affected by a disaster
c) The economic costs of disaster recovery
d) The total number of disasters in a year
a) The likelihood of a hazardous event occurring
Which of the following activities is part of emergency management?
a) Risk assessment
b) Disaster recovery
c) Preparedness
d) All of the above
d) All of the above
What global trend is affecting weather and climate hazards?
a) Decrease in population
b) Increased urbanization and global warming
c) Reduction in economic costs
d) Stabilization of geological hazards
b) Increased urbanization and global warming
What is the process by which planets, including Earth, formed from a spinning cloud of gas and dust?
a) Differentiation
b) Accretion
c) Erosion
d) Subduction
b) Accretion
Explanation: Accretion is the process where particles of gas, dust, and rock collide and combine to form larger bodies, eventually leading to planet formation.
What are the two main layers that Earth differentiates into after accretion?
a) Oceanic crust and continental crust
b) Core and mantle
c) Atmosphere and hydrosphere
d) Lithosphere and asthenosphere
b) Core and mantle
Explanation: After accretion, Earth undergoes differentiation, resulting in the formation of a dense metallic core and a lighter silicate-rich mantle.
How old is Earth, based on radiometric dating of meteorites?
a) 4.0 billion years
b) 4.5 billion years
c) 5.0 billion years
d) 3.5 billion years
b) 4.5 billion years
Explanation: Radiometric dating of meteorites shows that Earth formed approximately 4.55 billion years ago, a figure that has remained consistent with scientific findings.
What type of extraterrestrial bodies commonly cause impact events on Earth?
a) Moons
b) Stars
c) Asteroids and comets
d) Planets
c) Asteroids and comets
Explanation: Impact events on Earth primarily involve asteroids and comets, which can collide with Earth and cause significant damage depending on their size and speed.
What is a significant hazard that can result from a coronal mass ejection?
a) Increased volcanic activity
b) Earthquakes
c) Damage to spacecraft electronics
d) Flooding
c) Damage to spacecraft electronics
Explanation: Coronal mass ejections can release large amounts of charged particles that, when directed at Earth, can disrupt electronics in spacecraft and affect communication systems.
What is the lithosphere?
a) The rigid outer layer of Earth, including the crust and upper mantle
b) The inner core of the Earth
c) The fluid outer core
d) The entire mantle
a) The rigid outer layer of Earth, including the crust and upper mantle
Explanation: The lithosphere is the rigid layer composed of the crust and the uppermost part of the mantle, which behaves as a solid and is involved in tectonic processes.
What is the primary mechanism that explains how Earth’s lithosphere is divided into plates?
a) Seafloor spreading
b) Mantle convection
c) Subduction
d) Continental drift
b) Mantle convection
Explanation: Mantle convection is the primary mechanism driving the movement of the lithospheric plates, which are rigid and move relative to each other.
What type of plate boundary is characterized by two plates moving apart?
a) Convergent boundary
b) Divergent boundary
c) Transform boundary
d) Triple junction
b) Divergent boundary
Explanation: Divergent plate boundaries are where two tectonic plates move apart, leading to the formation of new lithosphere as mantle material rises.
What occurs at subduction zones?
a) New lithosphere is created
b) Lithosphere is consumed
c) Plates slide past each other
d) Continental plates collide
b) Lithosphere is consumed
Explanation: In subduction zones, one plate, typically the denser oceanic plate, plunges back into the mantle beneath a lighter plate, consuming lithosphere.
What geological feature is often associated with convergent boundaries where oceanic plates are involved?
a) Mid-ocean ridges
b) Mountain ranges
c) Deep ocean trenches
d) Hot spots
c) Deep ocean trenches
Explanation: Subduction zones are commonly associated with deep ocean trenches, which form where one tectonic plate is being forced under another.
Which of the following describes a strike-slip boundary?
a) Plates move toward each other
b) Plates move apart
c) Plates slide past one another
d) Plates sink beneath one another
c) Plates slide past one another
Explanation: Strike-slip boundaries involve two plates that move laterally past each other, with no creation or destruction of lithosphere.
What is a hot spot in geological terms?
a) A type of plate boundary
b) An area of seismic activity along a fault line
c) A location above an upwelling mantle plume
d) A region where tectonic plates collide
c) A location above an upwelling mantle plume
Explanation: Hot spots are volcanic regions formed by upwelling mantle plumes, resulting in volcanism that is not necessarily associated with plate boundaries.
What does isostasy refer to?
a) The process of mountain formation
b) The balance of buoyancy between Earth’s crust and mantle
c) The sinking of tectonic plates
d) The creation of oceanic crust
b) The balance of buoyancy between Earth’s crust and mantle
Explanation: Isostasy refers to the gravitational equilibrium where different segments of Earth’s crust float at levels determined by their densities.
What is the point on a fault plane where slip begins during an earthquake called?
a) Epicenter
b) Hypocenter
c) Focal point
d) Origin time
b) Hypocenter
Explanation: The hypocenter is the point on the fault plane where the slip initiates during an earthquake, while the epicenter is directly above it on the Earth’s surface.
Which type of fault accommodates horizontal extension?
a) Thrust fault
b) Normal fault
c) Strike-slip fault
d) Reverse fault
b) Normal fault
Explanation: Normal faults accommodate horizontal extension, with one side of the fault sliding down relative to the other.
What type of motion occurs in a thrust fault?
a) Lateral motion
b) Vertical extension
c) Horizontal compression
d) Vertical compression
c) Horizontal compression
Explanation: Thrust faults are characterized by horizontal compression, where one block is thrust over another.
What are the two main categories of seismic waves?
a) Surface and body waves
b) Longitudinal and transverse waves
c) Primary and secondary waves
d) P-waves and S-waves
a) Surface and body waves
Explanation: Seismic waves are classified into two main categories: body waves, which travel through the Earth’s interior, and surface waves, which travel along the surface.
What is the primary difference between P-waves and S-waves?
a) P-waves travel faster than S-waves
b) S-waves can pass through liquids, while P-waves cannot
c) P-waves cause more damage than S-waves
d) S-waves arrive first at seismometers
a) P-waves travel faster than S-waves
Explanation: P-waves (primary waves) are the fastest seismic waves and always arrive first at seismometers. S-waves (secondary waves) are slower and arrive after P-waves.
What does the earthquake cycle describe?
a) The movement of tectonic plates
b) The process of rock formation
c) How stress on a fault builds up and is released
d) The types of seismic waves produced
c) How stress on a fault builds up and is released
Explanation: The earthquake cycle describes the gradual buildup of stress on a fault due to tectonic forces, followed by a sudden release of that stress during an earthquake.
What do focal mechanisms represent?
a) The depth of an earthquake
b) The location of a fault
c) The type of faulting involved in earthquakes
d) The amount of damage caused by an earthquake
c) The type of faulting involved in earthquakes
Explanation: Focal mechanisms graphically represent the type of faulting associated with an earthquake, showing the movement of the fault during seismic events.
What does the magnitude of an earthquake describe?
a) The depth of the earthquake
b) The energy released during the earthquake
c) The duration of shaking
d) The intensity of shaking experienced
b) The energy released during the earthquake
Explanation: The magnitude of an earthquake describes how energetic it is, quantifying the energy released during the event.
Which scale was originally developed by Charles Richter to measure earthquake magnitude?
a) Moment magnitude scale
b) Modified Mercalli Intensity scale
c) Richter scale
d) Seismic moment scale
c) Richter scale
Explanation: The Richter scale was the original scale developed by Charles Richter to measure earthquake magnitudes based on seismic wave amplitudes.
How is the moment magnitude (Mw) related to the seismic moment (M₀)?
a) Mw = (M₀ + 9)/1.5
b) Mw = (logM₀ − 9)/1.5
c) Mw = (M₀ × 10)/1.5
d) Mw = logM₀ + 1.5
b) Mw = (logM₀ − 9)/1.5
Explanation: The moment magnitude (Mw) is related to the seismic moment (M₀) using the equation Mw = (logM₀ − 9)/1.5.
What are earthquakes with a moment magnitude (Mw) greater than 8 referred to as?
a) Major earthquakes
b) Great earthquakes
c) Subduction earthquakes
d) Intense earthquakes
b) Great earthquakes
Explanation: Earthquakes with a moment magnitude greater than 8 are referred to as “great earthquakes,” typically occurring in subduction zones.
What is the main distinction between earthquake magnitude and intensity?
a) Magnitude measures ground shaking; intensity measures energy release
b) Magnitude is a measurement of shaking effects; intensity measures energy release
c) Magnitude measures energy released; intensity measures effects on people and structures
d) Magnitude is measured using seismometers; intensity is measured using accelerometers
c) Magnitude measures energy released; intensity measures effects on people and structures
Explanation: Magnitude quantifies the energy released by the earthquake, while intensity describes the effects and shaking experienced by individuals and structures.
What is the Modified Mercalli Intensity (MMI) scale used to assess?
a) The energy released by an earthquake
b) The ground shaking effects as perceived by humans
c) The location of earthquake epicenters
d) The depth of earthquakes
b) The ground shaking effects as perceived by humans
Explanation: The Modified Mercalli Intensity (MMI) scale assesses the effects of an earthquake based on human perception and observed damage.
Which factor does NOT affect the level of ground shaking experienced during an earthquake?
a) Distance from the epicenter
b) Earthquake depth
c) Time of day
d) Regional geology
c) Time of day
Explanation: The time of day does not influence the level of ground shaking experienced during an earthquake. Factors such as distance from the epicenter, depth, and regional geology are more significant.
What type of earthquake ruptures the shallow plate interface at subduction zones?
a) Intermediate depth earthquakes
b) Forearc earthquakes
c) Megathrust earthquakes
d) Outer rise normal faulting earthquakes
c) Megathrust earthquakes
Explanation: Megathrust earthquakes occur at the shallow plate interface in subduction zones, where one plate is thrust over another.
What unusual characteristic did the 2011 Mw 9.0 Tohoku earthquake have?
a) It was the first megathrust earthquake recorded.
b) The seismic rupture extended to the sea floor.
c) It occurred at a depth of 300 km.
d) It was a volcanic earthquake.
b) The seismic rupture extended to the sea floor.
Explanation: The Tohoku earthquake was notable for its seismic rupture extending all the way to the sea floor, generating a significant tsunami.
Which type of earthquake occurs within the downgoing oceanic lithosphere at depths of 50–300 km?
a) Megathrust earthquakes
b) Intraplate earthquakes
c) Intermediate depth earthquakes
d) Forearc earthquakes
c) Intermediate depth earthquakes
Explanation: Intermediate depth earthquakes occur within the downgoing oceanic lithosphere at depths of approximately 50–300 km.
What is a significant characteristic of deep earthquakes?
a) They always cause widespread damage.
b) They occur in warm and ductile material.
c) They can reach depths of up to 700 km.
d) They are typically associated with volcanic activity.
c) They can reach depths of up to 700 km.
Explanation: Deep earthquakes can occur at depths of up to 700 km, but they typically do not cause significant damage due to their depth.
In continental plate boundary zones, what is the maximum magnitude that earthquakes generally reach?
a) Mw 8
b) Mw 7
c) Mw 6
d) Mw 9
a) Mw 8
Explanation: In continental plate boundary zones, earthquakes are usually limited to magnitudes of Mw < 8, with most being lower.
What is a common cause of intraplate earthquakes?
a) High latitude postglacial rebound
b) Subduction zone dynamics
c) Seismic waves traveling through the crust
d) Oceanic lithosphere flexing
a) High latitude postglacial rebound
Explanation: One common cause of intraplate earthquakes is the lithosphere’s flexing due to high latitude postglacial rebound.
What mechanism explains the recent increase in earthquake rates in regions such as northeastern BC and Oklahoma?
a) Natural tectonic stresses
b) Postglacial rebound
c) Induced earthquakes from fracking
d) Megathrust faulting
c) Induced earthquakes from fracking
Explanation: The increase in earthquake rates in certain regions can be attributed to induced earthquakes caused by the injection of fracking wastewater.
What is considered the best way to reduce deaths during an earthquake?
a) Improving earthquake prediction methods
b) Preventing buildings from collapsing
c) Increasing emergency response teams
d) Enhancing public awareness campaigns
b) Preventing buildings from collapsing
Explanation: The statement “Earthquakes don’t kill people, buildings do” emphasizes that preventing building collapses is the most effective way to reduce casualties.
Which type of building material is especially susceptible to collapse during an earthquake?
a) Wood
b) Steel
c) Masonry
d) Reinforced concrete
c) Masonry
Explanation: Masonry buildings, made of bricks and mortar, are particularly vulnerable to collapse during earthquakes compared to wood and steel-framed buildings, which offer more flexibility.
What does base isolation do?
a) Reinforces building foundations
b) Decouples larger buildings from horizontal ground motions
c) Adds additional weight to structures
d) Prevents vertical movement of buildings
b) Decouples larger buildings from horizontal ground motions
Explanation: Base isolation is a method that allows buildings to move independently from ground movements, reducing the resonance effects of earthquakes.
Which of the following is true about earthquake prediction?
a) It can accurately determine the exact time and magnitude of an earthquake.
b) Predictions rely on precursory events that can be detected in advance.
c) Most proposed methods pass scientific tests consistently.
d) Only a small percentage of large earthquakes have detectable foreshocks.
d) Only a small percentage of large earthquakes have detectable foreshocks.
Explanation: Most proposed prediction methods rely on foreshocks, but only a few large earthquakes show detectable foreshocks prior to the main event.
What is the primary focus of earthquake forecasting?
a) To provide immediate warning of an impending earthquake
b) To assess the likelihood of an earthquake occurring over a longer timescale
c) To predict the exact time and location of an earthquake
d) To prevent earthquakes from occurring
b) To assess the likelihood of an earthquake occurring over a longer timescale
Explanation: Earthquake forecasting aims to determine the probability of future earthquakes based on geological data rather than providing immediate warnings.
What technology allows for rapid assessment of an earthquake’s location and magnitude?
a) Earthquake mitigation
b) Earthquake early warning systems
c) Building retrofitting
d) Seismic forecasting
b) Earthquake early warning systems
Explanation: Earthquake early warning systems assess earthquake characteristics using dense seismometer networks to inform communities before damaging waves arrive.
What role does the USGS’ PAGER algorithm serve in the aftermath of an earthquake?
a) It provides public awareness of earthquake preparedness.
b) It estimates the number of fatalities based on various factors.
c) It predicts the next likely earthquake.
d) It reinforces building codes.b) It estimates the number of fatalities based on various factors.
Explanation: The PAGER algorithm provides rapid estimates of fatalities and impacts based on recorded intensities and population density.
Why is it important to reach earthquake victims quickly?
a) Most victims can survive for up to a week without help.
b) It is rare for victims to survive more than three days buried in rubble.
c) It helps reduce the overall cost of disaster response.
d) Authorities need to control the narrative about the earthquake.
b) It is rare for victims to survive more than three days buried in rubble.
Explanation: Quick rescue is crucial because the likelihood of survival decreases significantly after three days for those trapped in collapsed structures.
Why was Sumas Prarie near Abbotsford the worst impacted area during the BC flooding in November 2021?
Because this is an area especially susceptible to landsliding, which naturally increases the risks of flooding.
Because this area is mainly farmland and is designed to flood when any river in the area bursts its banks.
Because this is a drained former lake bed fed by a rerouted river.
Because this is where several rivers converge to form the Fraser River.
Because this is a drained former lake bed fed by a rerouted river.
People are drawn to building and living on floodplains for the reason of:
Safety from landslides.
Fertile land for farming.
Inexpensive real estate.
Easier transportation.
Fertile land for farming.
Flash floods involve torrential rainfall over what time period?
<6 hours
> 24 hours
<12 hours
<1 hour
<6 hours
At what time of year does flooding peak in Canada?
Spring (March, April, May)
Winter (December, January, February)
Summer (June, July, August)
Fall (September, October, November)
Flooding in Canada peaks in the spring (March, April, May). This is primarily due to snowmelt and ice jams as temperatures rise, causing rivers to overflow. Spring rainstorms can also contribute to flooding during this time.
What is the definition of a 100-year floodplain?
An area which is flooded once every 100 years.
An area which last flooded 100 years ago
An area with a 1% chance of flooding in any year.
An area with a 100% chance of flooding in any century.
An area with a 1% chance of flooding in any year.
A 100-year floodplain refers to the area that has a 1% probability of experiencing a flood in any given year. This does not mean flooding happens exactly once every 100 years—it’s a statistical probability.
Outburst floods are caused by:
Catastrophic failure of natural dams.
Intense local precipitation.
Structural failure of man-made infrastructure.
Sustained rainfall, often from hurricanes.
Catastrophic failure of natural dams.
Outburst floods occur when natural dams, such as those formed by glaciers, landslides, or ice, fail suddenly, releasing large volumes of water.
Hydro-meteorological floods are caused by:
Rainfall
Snowmelt
Ice jams
All of the above
All of the above
Hydro-meteorological floods can be caused by rainfall, snowmelt, and ice jams, as all of these are related to weather and water processes.
Which section of North America’s coastline is most vulnerable to storm surges?
The Gulf of Saint Lawrence
The Gulf of Alaska
The west coast, between California and B.C.
The eastern seaboard of the U.S., between East Florida and Maine
The Gulf of Mexico between Texas and South Florida
The Gulf of Mexico between Texas and South Florida
This region is particularly vulnerable to storm surges due to its warm waters, low-lying coastline, and frequent tropical storms and hurricanes, which can generate significant storm surges.
What is a jökulhlaup?
Another name for a glacial erratic (boulder dropped by glaciers).
An outburst flood from a glacier.
A volcano in Iceland with a glacier on top.
A flood caused by a landslide.
An outburst flood from a glacier.
A jökulhlaup is a sudden, catastrophic flood caused by the release of meltwater from a glacier or a glacially dammed lake, often triggered by volcanic activity beneath the ice or other factors that cause the ice to break. The term originates from Icelandic.
Where can ice jams cause flooding?
Both upstream and downstream of the ice jam
Upstream of the ice jam
Downstream of the ice jam
Both upstream and downstream of the ice jam
Ice jams can cause flooding upstream as water is blocked and backs up behind the jam, and downstream if the jam suddenly breaks, releasing a surge of water.
Which type of tropical cyclone is most common?
Typhoons in the West Pacific
Cyclones in the Indian Ocean
Hurricanes in the North Atlantic and NE Pacific
The most common type of tropical cyclone is Hurricanes in the North Atlantic and Northeast Pacific.
While all three types (typhoons, cyclones, and hurricanes) refer to the same phenomenon but occur in different regions, hurricanes are most frequently observed in the North Atlantic and Northeast Pacific regions. The North Atlantic hurricane season, which runs from June to November, is particularly active, with an average of 12 named storms each year. These areas experience higher frequency and intensity of tropical cyclones compared to the other regions.
What rise in global average sea-level do current climate models forecast happening this century (i.e. by 2100)?
Between 3 cm and 12 cm
Between 120 cm and 300 cm
Between 30 cm and 120 cm
Between 12 cm and 30 cm
Current climate models forecast a rise in global average sea level this century (by 2100) between 30 cm and 120 cm.
This range is based on different emissions scenarios and factors like the melting of glaciers and ice sheets, thermal expansion of seawater, and changes in land water storage. The specific rise depends on the level of greenhouse gas emissions and other factors influencing global temperatures.
Which hazard associated with tropical cyclones has caused the greatest number of fatalities, globally?
Landsliding
High wind speeds
Storm surges
Flooding from heavy rainfall
The hazard associated with tropical cyclones that has caused the greatest number of fatalities globally is storm surges.
Storm surges occur when strong winds push seawater onto coastal areas, leading to widespread flooding. This is often the most deadly aspect of tropical cyclones, as it can inundate large areas of land, cause significant damage to infrastructure, and result in a high number of casualties, especially in low-lying coastal regions.
According to which scale are tropical cyclones classified?
The moment magnitude scale.
The Saffir-Simpson scale.
The Mercalli intensity scale.
The Fujita scale.
Tropical cyclones are classified according to the Saffir-Simpson scale.
The Saffir-Simpson scale rates tropical cyclones (hurricanes or typhoons) based on their sustained wind speeds, ranging from Category 1 (least intense) to Category 5 (most intense). It helps to assess the potential damage and impacts of a storm.
In which region or regions of Canada are tornadoes most prevalent?
The mountainous West (British Columbia, western Alberta and the Yukon)
Northern Ontario and Quebec
The Atlantic region (Newfoundland and Labrador, Prince Edward Island, Nova Scotia, and New Brunswick)
Southern Ontario and the Prairie Provinces (Manitoba, Saskatchewan, and eastern Alberta)
Tornadoes are most prevalent in Southern Ontario and the Prairie Provinces (Manitoba, Saskatchewan, and eastern Alberta).
This region, often referred to as “Tornado Alley” in Canada, experiences the highest frequency of tornadoes. The combination of warm, moist air from the Gulf of Mexico and cooler, dry air from the north creates the ideal conditions for tornado formation, especially in the summer months.
In which part of Canada are extratropical cyclones most common?
The Great Lakes region of southern Ontario
The Pacific Coast of British Columbia
The Prairie Provinces: Manitoba, Saskatchewan, and Alberta
The Maritime Provinces: Nova Scotia, New Brunswick and Newfoundland
Extratropical cyclones are most common in the Maritime Provinces: Nova Scotia, New Brunswick, and Newfoundland.
This region is frequently impacted by extratropical cyclones, which are large storm systems that typically form over the ocean and bring heavy rain, strong winds, and sometimes snow, especially during the fall and winter months. The Maritime provinces are particularly vulnerable due to their proximity to the Atlantic Ocean, where these cyclones often develop.
According to which scale are tornadoes classified?
The Mercalli intensity scale
The Saffir-Simpson scale
The moment magnitude scale
The Fujita scale
Tornadoes are classified according to the Fujita scale (or the Enhanced Fujita scale, EF scale).
The Fujita scale rates tornadoes based on the damage they cause to buildings and vegetation, ranging from EF0 (weakest) to EF5 (strongest). The Enhanced Fujita scale (EF scale) is the updated version and is used in most areas today, refining the damage criteria for more accurate classification.
What distinguishes a hurricane, a cyclone, and a typhoon?
Their location (they occur over different regions of the oceans).
Their intensity (they have different peak wind speeds).
Their size (they have different surface areas).
Their duration (they last different lengths of time).
What distinguishes a hurricane, a cyclone, and a typhoon is their location – they occur over different regions of the oceans.
Hurricanes occur in the North Atlantic, Northeast Pacific, and South Pacific.
Typhoons occur in the Northwest Pacific (western part of the Pacific Ocean).
Cyclones occur in the Southwest Indian Ocean and North Indian Ocean.
These terms describe the same type of storm, but the name varies depending on the region where it forms.
Why are tornadoes so prevalent in the American Midwest?
Because tornadoes require warm air temperatures, and this region experiences the warmest summers in North America.
Because tornadoes require flat topography, and this is the flattest region in North America.
Because tornadoes require atmospheric instabilities, and several distinct air masses converge in this region.
ornadoes are so prevalent in the American Midwest because tornadoes require atmospheric instabilities, and several distinct air masses converge in this region.
The Midwest, particularly in areas like “Tornado Alley,” experiences frequent tornadoes due to the interaction of warm, moist air from the Gulf of Mexico, cold, dry air from the Rocky Mountains, and cool air from the north. This creates strong atmospheric instability, which is ideal for the formation of tornadoes. The flat topography also contributes by allowing these different air masses to meet more easily.
Which of the following is not an anthropogenic source of greenhouse gases that contributes to global warming?
CO2
O3
CH4
SO2
The correct answer is SO2 (sulfur dioxide).
While CO2 (carbon dioxide), O3 (ozone), and CH4 (methane) are all greenhouse gases that contribute to global warming, SO2 is not. Sulfur dioxide primarily contributes to the formation of aerosols and can have a cooling effect on the climate by reflecting sunlight. However, it does not directly contribute to the greenhouse effect in the same way that CO2, O3, and CH4 do.
In the 1958 Lituya Bay tsunami, what was the approximate maximum local wave height?
5 meters.
50 meters.
500 meters.
5 kilometers.
In the 1958 Lituya Bay tsunami, the approximate maximum local wave height was 500 meters.
This extraordinary wave was generated by a massive landslide caused by an earthquake. The wave, which reached a height of around 1,720 feet (or 524 meters), is the tallest tsunami wave ever recorded.
What was the deadliest water wave on record?
The 27th March 1964 (Good Friday) Alaska tsunami.
The 22th May 1960 Valdivia (Chile) tsunami.
The 11th March 2011 Tohoku (Japan) tsunami.
The 26th December 2004 Indian Ocean tsunami.
The deadliest water wave on record was the 26th December 2004 Indian Ocean tsunami.
This catastrophic event was triggered by a massive undersea earthquake off the coast of Sumatra, Indonesia. The tsunami affected multiple countries around the Indian Ocean and resulted in over 230,000 fatalities, making it the deadliest tsunami in recorded history.
Do all oceans have the potential to host ocean-wide tsunamis?
Yes, but the Pacific Ocean has the highest likelihood.
No. Only the Pacific and Indian Oceans have tsunamis, because they contain most of the world’s subduction zones.
Yes, but the Indian Ocean has the highest likelihood.
Yes, all oceans have roughly equal numbers of tsunamis (proportional to their areas).
Yes, but the Atlantic Ocean has the highest likelihood.
The correct answer is Yes, but the Pacific Ocean has the highest likelihood.
All oceans have the potential to host ocean-wide tsunamis, but the Pacific Ocean has the highest likelihood of experiencing tsunamis due to the large number of active subduction zones around its perimeter (e.g., the “Ring of Fire”). These zones are where tectonic plates collide and create conditions conducive to powerful undersea earthquakes that can trigger tsunamis. The Indian Ocean and Atlantic Ocean can also experience tsunamis, but they occur less frequently compared to the Pacific.
Immediately after an earthquake has occurred, what are the critical pieces of information needed to assess whether or not a tsunami has been generated?
The earthquake location.
The earthquake magnitude.
The earthquake depth.
The earthquake mechanism (e.g. thrust/reverse faulting, normal faulting, strike-slip faulting).
All of the above.
The correct answer is All of the above.
To assess whether a tsunami has been generated after an earthquake, the following critical pieces of information are needed:
The earthquake location: This helps to determine if the earthquake occurred in a region that is near or under the ocean, which is necessary for generating a tsunami.
The earthquake magnitude: Larger earthquakes are more likely to generate tsunamis, especially those with a magnitude of 7.5 or higher.
The earthquake depth: Shallow earthquakes (typically less than 700 kilometers deep) are more likely to generate tsunamis, as they can displace large volumes of water.
The earthquake mechanism: The type of faulting (e.g., thrust/reverse faulting, normal faulting, strike-slip faulting) can influence whether the earthquake causes vertical displacement of the seafloor, which is a key factor in generating a tsunami.
Which of these BC cities has the highest tsunami hazard?
Victoria.
Vancouver.
Port Alberni.
Tsunami hazards are equally high in Victoria, Vancouver and Port Alberni.
The BC city with the highest tsunami hazard is Port Alberni.
Port Alberni is located in the Alberni Valley, which is situated along the west coast of Vancouver Island. It is particularly vulnerable to tsunami hazards because of its location at the head of a long, narrow inlet. Tsunamis generated by distant earthquakes can be amplified in this kind of setting, making the potential impact much greater compared to more exposed coastal areas like Victoria or Vancouver.
How is the hazard cascade that resulted in the 1929 Grand Banks tsunami best characterized?
An earthquake triggered a coastal rock slide that generated the tsunami.
An earthquake triggered a submarine landslide that generated the tsunami.
A coastal rock slide generated the tsunami.
A submarine landslide generated the tsunami.
An offshore earthquake generated the tsunami.
The hazard cascade that resulted in the 1929 Grand Banks tsunami is best characterized as:
An earthquake triggered a submarine landslide that generated the tsunami.
The 1929 event was caused by a magnitude 7.2 earthquake off the coast of Newfoundland, which triggered a massive submarine landslide on the continental slope. This landslide displaced a large volume of water, generating a tsunami that impacted the coast of Newfoundland.
Why were tsunami waves from the 11th March 2011 Tohoku (Japan) earthquake much higher in some coastal towns (e.g. Miyako) than in neighbouring towns the same distance from the tsunami source (e.g. Sendai)?
Because the shape of the coastline funnelled more of the wave energy into coastal gulfs and inlets.
Because the wind direction at the time of the tsunami pushed the waves northwards.
This effect is poorly understood, and appears to be due to random chance.
Because the shape of the coastline funnelled more of the wave energy into coastal gulfs and inlets.
In the case of the 2011 Tohoku tsunami, the varying wave heights in different coastal towns were largely due to the coastal geography. Certain areas, like Miyako, were located in bays or inlets where the shape of the coastline amplified the tsunami waves, concentrating more energy in those regions. This effect is known as wave focusing, where the waves are funneled and intensified by the natural coastal features.
Which country frequently affected by tsunamis has invested heavily in sea wall defences?
USA
Canada
Indonesia
New Zealand
Japan
The country that has frequently been affected by tsunamis and has invested heavily in sea wall defenses is Japan.
Japan is one of the most tsunami-prone countries in the world due to its location along the Pacific “Ring of Fire,” where tectonic activity is high. In response, Japan has invested significantly in tsunami defense infrastructure, including sea walls, coastal barriers, and early warning systems, to protect its coastal areas from the impact of tsunamis.
