Geologic Hazards Final Study Guide

What is meant by the term 100-year flood? Your answer should include something about the magnitude and the percent chance of happening in any given year.

'100-year flood' refers to intense floods or flooding that has a recurrence internal of every 100-years based on historical data. This flooding has a 1% chance of occurring in any given year. Magnitude is not set for 100-year floods, because it does not have to be large. It means that in any year there is a 1%, or 1 in 100, chance that a flood of a given magnitude will occur. Additionally, it magnitude depends on the size of the body of water that is flooding, such as a small stream will have a different magnitude to be considered a 100-year flood versus a river such as the Columbia or Willamette have a 100-year flood. Yes, 100-year floods can occur more than once in 100 years and more than 1 in a given year. The climate is changing and can affect the amount of precipitation received by bodies of water.

Hurricanes can be up to ________ miles in diameter. 50 100 250 500 1,000

1,000

The largest landslide in the world is over ________ thick and more than ________ in area. 50 feet, 100 square miles 100 feet, 200 square miles 1,000 feet, 400 square miles 2,000 feet, 500 square miles

1,000 feet, 400 square miles

Based on what you learned from the U.S. Geological Survey Earthquake Map, approximately how many earthquakes occur in the U.S. every week? less than 50 50 to 100 100 to 500 500 to 1000 1,000 to 2,000

1,000 to 2,000

According to this week's video (NOVA - Inside the Megastorm) what unusual meteorological conditions affected the path of Hurricane Sandy? List at least 3 unusual conditions.

1. An inland northeastern storm that was originally parallel to Hurricane Sandy moving up the East coast actually combined with Sandy. This made Sandy more intense. 2. The Bermuda high was absent in the scenario. The Bermuda High usually pushes hurricanes away from land and into the North Atlantic. So, the hurricane continued up the NE US coast. 3. The Gulf Stream usually pumps a stream of warm water from the Gulf of Mexico up across the Atlantic. This time, it was warmer than usual. The surface water tempers were up to 5 degrees warmer than usual. Warmer waters make for stronger hurricanes.

What four steps does the Pacific Tsunami Warning Center take to alert the public of possible tsunamis?

1. Locate the earthquake The locality of the earthquake is first determined. Important factors such as if it was an oceanic/near ocean earthquake, shallow or deep quake, and the magnitude of the quake are taken into account. 2. Determine tsunami travel time Tsunamis have predictable speed given the seafloor depth is known. Once enough information is known about the earthquake, tsunami speed can be determined. 3. Check sea level gauges for evidence of a tsunami Fixtures like ocean piers can be used to determine the local sea level of a location. DART (Deep-ocean Assessment and Reporting of Tsunamis) have buoys which are sensors and can determine sea level gauge and change. 4. Issue messages as appropriate If there is enough evidence for a tsunami and the magnitude threshold is met, than warnings are issued. Warnings in Hawai'i are issued in about 2-5 minutes, and the rest of the Pacific Rim will get warnings in about 10-20 minutes.

Describe 4 ways that levees can fail.

1. Seepage Water seeping through the levee or the levee foundation 2. Stability A section of the levee sloughing off because of water up against the levee 3. Erosion Toe erosion steepening the slope such that it becomes unstable and collapses and inundates. 4. Height More flow than what the levee is built for. The water eventually flows over the levee.

Describe three methods scientists use to monitor volcanoes for signs of activity. For each method, explain how the information is collected (what is measured, or what type of equipment is used), and what the information tells scientists about the volcano.

1. Volcano Hazards Program with the USGS monitors the chemical and gas make up of water near volcanoes. If there are increases in chemical content of the water and gas near a volcano, this could mean an eruption is near. 2. Around six to eight seismometers are placed along seismic networks (faults) which then can detect changes in the seismicity of an area near a volcano. Earthquakes are known to precede volcanic eruptions, and monitoring the seismicity may be a clue into a coming eruption. 3. GPS can be used to measure if a volcano has deformed or expanded using GIS units surrounding a volcano; this can clue in to the magma chamber expanding and churning beneath a volcano and leading to a possible eruption.

Scientists estimate there is a ____% chance of a M 9+ Cascadia earthquake occurring in the next ______ years and a ___% chance of a M 8+ Cascadia earthquake occurring in the next ____ years. The frequency of occurrence for these earthquakes is once every 500 years for a M 9+ earthquake, and once every 250 for a M 8+ earthquake. The last Cascadia earthquake occurred _____ years ago.

10 - 15 50 37 50 318

A large subduction zone earthquake in the Pacific Northwest will likely trigger a tsunami with waves ____ feet high and lasting up to ____ hours. 5-10 feet high, 8 hours 10-50 feet high, 8 hours 10-50 feet high, 2 hours 5-10 feet high, 2 hours We have no way of predicting how high the tsunami waves will be, or how long they will last

10-50 feet high, 8 hours

How many giant landslides have occurred in Hawaii during the past 4 million years? Could they occur again in the future?

15; Yes

Storm surges can be up to ______ high and can extend up to ________ along coastlines. 10 feet, 50 miles 20 feet, 50 miles 10 feet, 100 miles 20 feet, 100 miles

20 feet, 100 miles

What is the minimum number of seismograph stations a scientist must have data from in order to locate the epicenter of an earthquake? 1 2 3 4 It depends on where the earthquake occurs

3

What percentage of single-family homes in Portland were built before the first seismic codes, which means they are probably not bolted to their foundations and will be uninhabitable after a large Cascadia earthquake? 10% 30% 70% 90%

70%

Hurricanes can be up to ________ miles in height. 2 4.5 9 20

9

Which of the following is most likely to be a natural disaster? A highly explosive volcanic eruption on an uninhabited island A large earthquake in the middle of the Sahara desert An avalanche in central Greenland A flood on the Ganges River in Bangladesh A large tsunami along the coastline of Antarctica

A flood on the Ganges River in Bangladesh

A pyroclastic flow can best be described as: A flow of hot gas and ash A flow of hot gas A flow of mud and pyroclastic material A flow of hot lava A rain of volcanic fragments

A flow of hot gas and ash

A) Name two natural hazards we have discussed this term that can trigger landslides. B) Name at least one more natural hazard that we have not discussed, but that can also trigger landslides.

A) Earthquakes and volcanic eruptions B) Monsoons; heavy, torrential rainfall.

Part A) Explain the difference between a hurricane, cyclone, and typhoon. Part B) Explain the difference between a tropical depression, a tropical storm, and a hurricane.

A) Hurricanes, cyclones, and typhoons differ in the regions they form in: Hurricanes occur in the Atlantic and NE Pacific Oceans Cyclones occur in the West Pacific Typhoons occur in the Bay of Bengal and the Indian Ocean B) Tropical depressions, tropical storms, and hurricanes differ in their maximum sustained wind speeds (or relatively long lasting wind speeds): Tropical depressions have maximum sustained winds of 25 -38mph Tropical storms have maximum sustained winds of 73mph Hurricanes have maximum sustained winds of 74mph and over.

How high were the tsunami waves created by ancient landslides in Hawaii? About 50 feet (15 meters) About 100 feet (30 meters) About 500 feet (150 meters) About 1,000 feet (300 meters) We have no way of knowing how high these tsunami waves were

About 1,000 feet (300 meters)

How many people are killed by floods each year in the United States? Less than 10 people About 14 people About 140 people About 1,400 people We don't know how many people are killed by floods

About 140 people

How much economic damage is caused by floods each year in the United States? About 6 million dollars About 60 million dollars About 6 billion dollars About 60 billion dollars

About 6 billion dollars

Earthquake shaking is measured using the following scales: The Richter Scale The moment magnitude scale The Mercalli scale All of the above

All of the above

Earthquakes can occur along which of the following types of faults? Normal faults Reverse faults Strike-slip faults All of the above None of the above

All of the above

What evidence indicates that a large subduction zone earthquake occurred in the Pacific Northwest about 300 years ago? "Ghost forests" along the Pacific Northwest coast, these trees died about 300 years ago. Japanese records of a tsunami that occurred 316 years ago, but was not associated with an earthquake in Japan. Oral traditions from Native Americans living in coastal areas of the Pacific Northwest about 300 years ago. Subsidence of several feet along the coast of the Pacific Northwest, geologic evidence suggests this subsidence occurred about 300 years ago. All of the above

All of the above

What types of weather events are associated with a "wavy" polar jet stream? Tropical storms along the east coast, for example Hurricane Sandy. Severe snowstorms along the east coast. Droughts in the Midwest. Unusually cold winters in Europe All of the above. None of these events are associated with the jet stream.

All of the above

Which of the following are hazards that exist after flood waters recede? Pesticides and fuel Untreated sewage Dangerous mold blooms Waterborne diseases like typhoid, hepatitis A, and cholera All of the above

All of the above

Which of the following are the main parts of a hurricane? Eye Feeder bands Eye wall All of the above

All of the above

Which of the following can trigger landslides on volcanoes? Intrusion of magma into the volcano Explosive eruptions of the volcano Large earthquakes directly beneath or nearby the volcano Heavy rainfall that saturates the slopes of the volcano All of the above

All of the above

Which of the following describes "slow earthquakes"? Earthquakes that occur over a period of several weeks, rather than several seconds or minutes. Earthquakes that cannot be felt, even though they release the same amount of energy as a "normal" magnitude 6-7 earthquake. Earthquakes that occur about every 14-15 months in the Pacific Northwest. Earthquakes that might act as a warning for a much larger Cascadia earthquake. All of the above

All of the above

Which of the following is not a natural hazard? Tsunamis Wildfires Changes in Earth's magnetic field Dust storms Strong winds All of these are natural hazards

All of these are natural hazards

What parts of the world experience natural hazards?

All parts of the world experience natural hazards.

Most earthquakes occur: In the middle of oceanic and continental plates Along the edges of oceanic and continental plates In oceans and lakes Earthquakes are scattered equally around the globe

Along the edges of oceanic and continental plates

What is a levee? Structures that dam rivers (they are built perpendicular to the direction of river flow). Natural river banks that are elevated from the river bed. Structures built specifically to generate hydroelectric power along rivers. Manmade river banks that are elevated from the river bed. Answers A and C. Answers B and D

Answers B and D

When the polar jet stream gets "wavy" and moves slower, what happens to the weather patterns associated with it? Storms tend to stall out and stay in one place for longer. Storms tend to move more quickly through the region. Storms become more intense. Storms become less intense. Both A and C are correct. Both B and D are correct.

Both A and C are correct

Explain what caused the March 2011 earthquake in Japan and the December 2004 earthquake in Sumatra. How were these two events similar? Your answer should include a brief description of what is happening to the tectonic plates in both regions.

Both of these earthquakes are subduction quakes. In a subduction zone, the more dense plate, in this case the oceanic crust/plate, sinks below the less dense plate, the continental crust/plate. This sinking below causes sticking between the plates and uplift occurs on the top plate. When the sticking lets go, the plates slip, and an earthquake is generated. Tsunamis were generated from both of these quakes. The angle between the subducting plate and overriding plate in Sumatra was at a much smaller and shallower angle than the one in Japan.

Which of the following best describes how erosion of levees is fixed? The levee is constructed higher, or a flood wall is built. The levee is widened and flattened. Digging a trench into the levee and filling it with a watertight wall. Building a layer of rock to strengthen the levee and it's foundation.

Building a layer of rock to strengthen the levee and it's foundation.

Which of the following best describes how erosion of levees is fixed? The levee is constructed higher, or a flood wall is built. The levee is widened and flattened. Digging a trench into the levee and filling it with a watertight wall. Building a layer of rock to strengthen the levee and it's foundation.

Building a layer of rock to strengthen the levee and it's foundation.

Are natural hazards rare events or common events worldwide?

Common

The polar jet stream is created by: Unusually strong tropical storms. Convergence of cold air descending from the Arctic and warm air rising from the tropics. Convergence of warm air descending from the Arctic and cold air rising from the tropics. Warmer global temperatures associated with climate change.

Convergence of cold air descending from the Arctic and warm air rising from the tropics.

What type of plate boundaries generate the most tsunamis? Transform plate boundaries Divergent plate boundaries Convergent plate boundaries - continental collisions Convergent plate boundaries - subduction zones All types of plate boundaries generate tsunamis equally

Convergent plate boundaries - subduction zones

Because of the Coriolis Effect, hurricanes rotate_____ in the Northern Hemisphere and _____ in the Southern Hemisphere.

Counterclockwise Clockwise

What causes the polar jet stream to become "wavy"? (Be sure to include a description of what is happening to different air currents.)

Denser colder air sinks and pushes warm air up north. This forms waves though a series of ridges and troughs in the air flow. Warmer northern temperatures happen on account of less ice in the arctic, and this also creates a wavier jet stream. A jet stream is typically wavy, but this effect is dramatize with climate change effects.

Which of the following best describes how seepage from levees is fixed? The levee is constructed higher, or a flood wall is built. The levee is widened and flattened. Digging a trench into the levee and filling it with a watertight wall. Building a layer of rock to strengthen the levee and it's foundation.

Digging a trench into the levee and filling it with a watertight wall.

Which of the following tectonic features are associated with volcanic activity? Divergent plate boundaries Convergent plate boundaries Transform plate boundaries Hotspots None of the above

Divergent plate boundaries Convergent plate boundaries Hotspots

Which of the following is an example of a natural hazard that occurs slowly?: Volcanic eruptions Earthquakes Floods Droughts Landslides

Droughts

The most common cause of tsunamis is _________________.

Earthquakes

What types of events cause tsunamis? Choose all that apply. Earthquakes Landslides Forest fires Droughts Volcanic eruptions Meteor impacts Hurricanes Sea level rise

Earthquakes Landslides Volcanic eruptions Meteor impacts

When you created your own volcano on the National Geographic - Forces of NatureLinks to an external site. website, what criteria resulted in explosive eruptions? What criteria resulted in effusive eruptions? Of the four types of volcanoes listed in this exercise, which ones tend to erupt explosively? Which ones tend to erupt effusively?

Explosive eruptions occurred when there were high levels of silica and high levels of dissolved gas. Effusive eruptions occurred when there were low levels of silica and low levels of dissolved gas. Gas seems to be the defining factor in the explosively of the eruption, but high silica content does seem to be linked to more explosive eruptions and lower levels to more effusive. Composite (stratovolcanoes) and cinder cone volcanoes evolve from violent and explosive eruptions. Lava dome and shield volcanoes evolve from less violent and more effusive eruptions.

What is the most turbulent part of a hurricane? Eye Eye wall Feeder bands Outflow clouds All of the above

Eye wall

One way that Oregon and Washington have mitigated against loss of life during large tsunamis is by building vertical evacuation structures in all coastal towns and cities. True False

False

The best definition for the term volcano is a tall cone-shaped mountain that erupts lava. True False

False

Is an event like that described in Question 10 likely to occur? Highly likely Somewhat likely Highly likely Somewhat unlikely

Highly likely

Which of the following volcanic gases are hazardous to people, animals, agriculture, and property? Hydrogen halide (HF, HCl, HBr) Water vapor (H2O) Hydrogen sulfide (H2S) Carbon dioxide (CO2) Sulfur dioxide (SO2)

Hydrogen halide (HF, HCl, HBr) Hydrogen sulfide (H2S) Carbon dioxide (CO2) Sulfur dioxide (SO2)

Which of the following best describes creep (pertaining to landslides, not people): A landslide that consists of a single unit that moves downslope as a coherent mass. Abrupt movements of rocks or boulders that become detached from steep slopes or cliffs. Rapid mass movement of loose soil, rock, organic matter, and water that flows as a slurry downslope. Imperceptibly slow, steady, downward movement of soil or rock.

Imperceptibly slow, steady, downward movement of soil or rock.

When is the polar jet stream strongest? In summer months when the temperature difference between warm and cold air in the Northern Hemisphere is at its highest. In summer months when the temperature difference between warm and cold air in the Northern Hemisphere is at its lowest. In winter months when the temperature difference between warm and cold air in the Northern Hemisphere is at its highest. In winter months when the temperature difference between warm and cold air in the Northern Hemisphere is at its lowest.

In winter months when the temperature difference between warm and cold air in the Northern Hemisphere is at its highest.

Sudden melting of glaciers on volcanoes can generate which of the following hazards? Pyroclastic flows Earthquakes Lahars Lava flows Volcanic gases

Lahars

Which of the following is produced by the least explosive types of volcanic eruptions? Tephra (or volcanic ash) Lava flows Pyroclastic flows All of the above

Lava flows

Of the hundreds of storm systems generated in tropical regions every year, how many typically develop into hurricanes? All of them About 90% About 70% Less than 50% None of them

Less than 50%

According to this week's video (National Geographic - Top Ten Disasters), what four factors are used to rate the severity of a natural disaster? Choose four factors from the list below: Magnitude (size) of the event Type of event (flood, earthquake, etc.) Deaths caused by the event Economic damage cuased by the event Lasting legacy of the event Geographic location of the event

Magnitude (size) of the event Deaths caused by the event Economic damage cuased by the event Lasting legacy of the event

Explain in your own words what mitigation means. Give at least one example from this week's lecture or reading material of: 1) Ways we can mitigate as a society against earthquakes, 2) Ways we can mitigate as individuals against earthquakes.

Mitigation is the action of trying to lessen damage/intensity of an event before it occurs. Proactively trying to decrease the amount of buildings that are damaged rather than waiting for the earthquake to happen and then deal with it. 1). Building regulation codes for homes and businesses is a proactive societal way to deal with earthquake damage and intensity. By creating ShakeAlert, this is another proactive societal way to deal with earthquake damage and intensity by warning people to prepare for a coming quake. 2). Living near less seismically active locations is a way for individuals to mitigate earthquake damage and intensity.

How would you describe the path of the jet stream shown in the Boston Globe article? (The Boston Globe: Blame jet stream, arctic air for repeat snowstorms). (Links to an external site.) More "wavy" than usual, bringing heavy snow storms to New England. Less "wavy" than usual, causing storms to miss New England and travel out to sea. More "wavy" than usual, and traveling west instead of east. More "wavy" than usual, and traveling south instead of north.

More "wavy" than usual, bringing heavy snow storms to New England.

How old are the oldest levee systems in California? (And also throughout the rest of the country.) About 25 years old About 50 years old About 75 years old More than 100 years old

More than 100 years old

How are mudflows different from landslides? Mudflows are composed mostly of solid material (rocks, soil, trees, and debris), they contain more solid material than landslides. Mudflows are rivers of liquid and flowing mud, they contain less solid material than landslides. Mudflows and landslides are essentially the same thing, there is no physical difference between them. Mudflows only occur during winter months, landslides can occur any time of the year. Mudflows only occur during summer months, landslides can occur any time of year.

Mudflows are rivers of liquid and flowing mud, they contain less solid material than landslides.

What is the difference between natural phenomena (or natural events), natural hazards, and natural disasters?

Natural phenomena: ALL aspects of the natural world are natural phenomena. They can be harmless events like rainbows or sunsets, or extreme events like earthquakes or volcanic eruptions. Natural hazards: these are a subset of natural phenomena. Natural hazards are any natural phenomena that pose a threat to human populations. They might not actually result in a disaster, but they do pose a threat to people. Natural disasters: these are a subset of natural hazards. Natural disasters are hazards that actually DO have a major impact on human populations, rather than just threatening human populations.

What parts of the world are impacted by the northern polar jet stream? North America South America Europe Africa Asia Australia Antarctica

North America Europe Asia

To determine how far away from a seismograph station an earthquake occurred, scientists plot the difference in arrival times between: P and S waves S and L waves P and L waves Seismic waves and tsunami waves All of the above

P and S waves

Which type of seismic waves travel the fastest? L waves P waves S waves Surface wave All seismic waves travel at the same speed

P waves

Which of the following best describes debris flows: A landslide that consists of a single unit that moves downslope as a coherent mass. Abrupt movements of rocks or boulders that become detached from steep slopes or cliffs. Rapid mass movement of loose soil, rock, organic matter, and water that flows as a slurry downslope. Imperceptibly slow, steady, downward movement of soil or rock.

Rapid mass movement of loose soil, rock, organic matter, and water that flows as a slurry downslope.

What is a reinsurance company? Why do these companies have a special interest in keeping track of natural hazards and natural disasters?

Reinsurance companies are companies which sell insurance to other insurers, and can be seen as "natural disaster insurance". These companies will be responsible for coverage in the event of things like major flooding or wildfires (natural hazards/disasters), and are in the business of risk management/mitigation.

Describe how early warning systems for earthquakes (for example, Shake Alert) rely on differences in the arrival times of P-waves and S-waves to give people time to prepare for earthquakes. Also include at least three examples of the types of precautions these systems allow allow for.

ShakeAlert detects and measures p-waves (primary waves) and sends out warnings to those who are in danger of an earthquake to allow for some seconds to minutes of preparation before the more violent s-waves (secondary waves). These alerts halt some operations, such as gas mains to shut and close, trains to stop immediately, and alarm sounding systems warning populations to get to safe areas. And P-waves travel faster, which is why they are registered first by the early warning systems. S-waves travel slower and will arrive seconds to minutes later

Which of the following is the most common cause of landslides? Earthquakes Volcanic eruptions Tsunamis Meteor impacts Slope saturation by water

Slope saturation by water

What is the most dangerous result of a hurricane once it reaches land? High winds Heavy rain Storm surge Lightning strikes Zombie attacks

Storm surge

Match each of the following photos with the type of volcano or volcanic feature that best describes it. Photo 1: Mt. Hood Photo 2: Mauna Loa Photo 3: Lava Butte 2 Photo 4: Fort Rock 2 Photo 5: Crater Lake Photo 6: Fissure Eruption 1

Stratovolcano Shield volcano Cinder cone Tuff ring Caldera Volcanic fissure

Which of the following hazards are closely associated with earthquakes? Choose all that apply. Subsidence Liquefaction Ground displacement Flooding Tsunamis Fires

Subsidence Liquefaction Ground displacement Flooding Tsunamis Fires

In all cases, tsunamis waves are caused by: Earthquakes High tides Sudden displacement of water Storms Volcanic eruptions

Sudden displacement of water

In general, the most destructive earthquake waves are __________ . P waves S waves Surface waves Q waves All seismic waves travel at the same speed

Surface waves

Which of the following is the most widespread and frequent volcanic hazard? Tephra (or volcanic ash) Lava flows Pyroclastic flows All of the above

Tephra (or volcanic ash)

Which of the disasters covered in the video was the most economic costly disaster in human history? Hurricane Katrina The 1906 San Francisco earthquake The 2011 Japanese earthquake and tsunami The Black Death (or bubonic plague) in Europe The Ice Age Megaflood

The 2011 Japanese earthquake and tsunami

How will a Cascadia earthquake impact transportation in Portland? Your answer should describe at least four major impacts on transportation.

The Hawthorne, Steel, and Interstate bridges will most likely collapse and so will many ramps leading up to all bridges. Since many streets are built on alluvial deposits they will crack and fall a part. The West Hill's Tunnel is not seismically retrofitted and may collapse. Road clearing equipment is stored under Fremont Bridge ramps and may be unable to be accessed. The pipe which delivers most of the fuel to Portland is an older pipe, from the 1960s, and was not built to withstand large quakes and so it may snap. Tilikum, Sellwood, and the Skytram are built to withstand large quakes. The boats along Portland's rivers, like the Portland Spirit, will become ferries in the aftermath. If bridges connecting Portland to the rest of the state are damaged there are hundreds of thousands of people trapped on either side from receiving emergency rescue or care. The tunnel may inhibit rescue from going in or out of the city. The lack of fuel will make it impossible for people to try and flee in cars and may leave emergency vehicles without fuel as well. The lack of road clearing equipment means roads will take a long time to be cleared to be fixed and then for use.

Which of the following measures an earthquake's intensity based on the observed effects on people and structures? The Richter Scale The moment magnitude scale The Mercalli scale All of the above

The Mercalli Scale

Describe the two most effective methods of landslide mitigation, or how to reduce the effects of landslides. If either of these methods needs further explanation (for example, details about how landslide hazards are reduced) include this in your explanation.

The best way to mitigate landslide damage is to not build near landslide prone areas (helpful use of hazard maps!) and to not do any activity which could cause a landslide prone slope to slip. For instance, not building on slopes and limiting the filtration of water into that slope are ways to mitigate the threat of a landslide. Also, building retaining walls could help mitigate damage from shallower landslides on nearby communities.

How many deaths are estimated to occur in Portland due to building collapse? List 4 preparations Portland has made to mitigate deaths from building collapse.

The death toll is estimated to be between 650-6,000. 1. A $482 million bond was approved in 2012 which will allow schools to be seismically retrofitted in Portland so they can withstand large quakes. 2. $100,000 in FEMA provided funds has allowed for 22 homeowners to bolt their homes to their foundation to prevent a total collapse and devastation of homes and deaths associated with that. 3. Portland's Fire Bureau was able to retrofit/rebuild all 30 facilities to be able to withstand a large quake 4. Hazard maps are available for every neighborhood that include evacuation routes, hospital locations, and other emergency services in the Portland area, which can mitigate deaths caused by staying in buildings in the hazard zone.

Which of the following best describes how the height of levees is fixed? The levee is constructed higher, or a flood wall is built. The levee is widened and flattened. Digging a trench into the levee and filling it with a watertight wall. Building a layer of rock to strengthen the levee and it's foundation.

The levee is constructed higher, or a flood wall is built.

Which of the following best describes how the stability of levees is fixed? The levee is constructed higher, or a flood wall is built. The levee is widened and flattened. Digging a trench into the levee and filling it with a watertight wall. Building a layer of rock to strengthen the levee and it's foundation.

The levee is widened and flattened.

What part of the atmosphere do winds in the polar jet stream travel? The upper layers of the atmosphere, where they have little influence on weather. The middle layers of the atmosphere, where they can sometimes influence weather. The lower layers of the atmosphere, where they have a strong influence on weather. Winds in the jet stream travel in all of these layers.

The lower layers of the atmosphere, where they have a strong influence on weather.

According to the interactive map showing landslides in Oregon, where do most landslides in the state occur? What two factors do you think have the most influence on where landslides occur in Oregon? Your answer should explain why the majority of landslides occur where they do, and why landslides are less common in other regions of the state.

The places with the greatest amount of landslides and the places with the highest risk of a landslide occurring seems to be the Coast and Cascade Mountain Ranges. I believe the fact these areas are elevated terrain and the fact Oregon is a very rainy place allow for these mountainous regions to be susceptible to slip and cause landslides. Flatter areas of the state, like the Willamette Valley and much of eastern Oregon, are less prone even though there is rain throughout the state, but without the elevated terrain there is a less (if not nonexistent) threat of a landslide.

When you created your own hurricane, what 3 things were needed in order to generate a hurricane? Of the 5 hurricanes you generated, which one had the greatest intensity? What category was this hurricane?

The three things required for a hurricane to form is: 1. Warm ocean temperatures 2. High humidity 3. Low pressure The fifth hurricane I created with these conditions was the most destructive. It was formed in the Gulf of Mexico near the Yucatan Peninsula. It was a category 5 with wind speeds topping 155mph. It also would require massive evacuations.

What 3 general regions of the United States are most susceptible to landslides? The west coast The east coast The Gulf coast The Rocky Mountain region The Midwest The Appalachian region

The west coast The Rocky Mountain Region The Appalachian region

Why are the regions you chose in Question 4 more susceptible to landslides than other parts of the U.S.?

These areas are elevated terrain and receive a substantial amount of precipitation.

What is the effect of wind shears on hurricanes? They make hurricanes stronger They make hurricanes weaker They increase wind speeds They increase storm surges All of the above

They make hurricanes weaker

If a large asteroid landed in the Pacific Ocean between the Hawaiian Islands and the west coast of North America, what would be the impact of the tsunami waves? They would cover the entire U.S. They would cover all of North America. They would wash out coastal cities on the west coasts of Canada, the U.S. and Mexico, and would cover most of the coastal areas of Hawaii. They would wash out coastal cities on the east coasts of Canada, the U.S. and Mexico, and would cover most of the coastal areas of the Caribbean Islands. They would cover the western half of the U.S. They would cover the eastern half of the U.S.

They would wash out coastal cities on the west coasts of Canada, the U.S. and Mexico, and would cover most of the coastal areas of Hawaii.

What direction do winds in the polar jet stream travel? Toward the north Toward the south Toward the west Toward the east

Toward the East

In general, subduction zone earthquakes in the Pacific Northwest are much larger than any recorded earthquake that has occurred in California. True False

True

Winds in the polar jet stream can travel at speeds greater than 100 mph. True False

True

This week's video showed layers of sand that Brian Atwater found in the pits he dug along the coast of Oregon and Washington. Which of the following best describes how these layers of sand were deposited? Earthquakes Hurricanes Tsunamis Floods Landslides

Tsunamis

Based on this week's reading materials, and this week's and last week's videos, how long could the shaking last during a large Cascadia earthquake? A few seconds Up to a minute Up to two minutes Up to five minutes We have no way of predicting how long the shaking during subduction zone earthquakes could last

Up to five minutes

Based on the information in Question 4, how seriously should the general population take the threat of large earthquakes occurring in Oregon? Not seriously Somewhat seriously Very seriously There is no basis for public to asses the threat of large earthquakes in Oregon.

Very seriously

Which of the following is the most common type of volcanic gas? Hydrogen halide (HF, HCl, HBr) Water vapor (H2O) Hydrogen sulfide (H2S) Carbon dioxide (CO2) Sulfur dioxide (SO2)

Water vapor (H2O)

Once tsunami waves wash inland in populated areas, what do they consist of? Water only Water and sediments (mud, soil, etc) Water, sediments, and natural debris (trees and other vegetation) Water, sediments, natural debris, and manmade debris (houses, cars, boats, etc.)

Water, sediments, natural debris, and manmade debris (houses, cars, boats, etc.)

What parts of the U.S. are at the highest risk for earthquakes? Choose all that apply. Only California is at significant risk for earthquakes Western states, especially Washington, Oregon, Nevada, and California Most of Alaska Hawaii, especially the big island of Hawaii The Great Lakes region The region near the borders of Kentucky,Tennessee, Arkansas, and Missouri States that border the Gulf of Mexico, especially Texas, Louisiana, and Florida

Western states, especially Washington, Oregon, Nevada, and California, Most of Alaska, Hawaii especially the big island of Hawaii, The region near the borders of Kentucky,Tennessee, Arkansas, and Missouri

Can hurricanes spawn tornadoes? Yes No Scientists are not sure

Yes

Based on what you learned from the Smithsonian/U.S. Geological Survey Weekly Volcanic Activity Report website, how many volcanoes are usually erupting worldwide? about 20 about 100 about 500 about 1,000

about 20

In deep water, tsunamis move at _____________. When they reach shallow water in coastal areas, the tsunami _____________ and ____________ in height. Slow speeds, speeds up, increases Slow speeds, speeds up, decreases fast speeds, slows down, increases fast speeds, slows down, decreases

fast speeds, slows down, increases

Where in the U.S. do landslides occur? In all 50 states. Only in states with steep topography. Only in states that get a lot of precipitation. Only in mountainous states. Only in coastal states.

in all 50 states

Rising temperatures in the arctic make the jet stream _________ "wavy," increasing the likelihood of ________severe storms. less; less less; more more; less more; more Rising temperatures in the arctic do not impact the jet stream.

more; more

Do typical homeowners insurance policies cover geologic hazards like landslides? yes no

no

According to the World Meteorological Organization, every dollar that is invested in disaster preparedness can prevent ________ in economic losses related to disasters.

seven dollars