GEOL 111 (summer 2020)

Marine organisms preserve the current oxygen-isotope ratio in their _______________.

shells

The recurrence interval for a flood of a given magnitude is defined as...

the average number of years between occurrences of a flood of that magnitude or greater.

Why does the damming of rivers sometime contribute to coastal erosion?

the supply of new sand to replenish beaches is cut off

When waves approach the shore and enter shallow water

the waves slow down and the wave height increases

What effect do groins, breakwaters, and jetties have on coastal erosion?

they interrupt the transport of sand down the beach front

As a result of mass movements on the slope above the Vajont Dam, _______.

water levels in the reservoir were raised and lowered several times in an attempt to reach hydraulic equilibrium between the water level in the reservoir and the nearby rocks.

​Why is it warmer in the northern hemisphere in July than it is in December?

​The sun's rays shine more directly on the northern hemisphere in the summer than in the winter.

In a single year, which of the following is the largest emitter of carbon dioxide into Earth's atmosphere?

​coal-fired power plants

The effect of aerosols can be best described as ____.

​reflecting sunlight and cooling the atmosphere

Select the 3 methods inspired by the 1993 Flood to prevent future damage and loss from flooding. 1. Elevating homes above flood level 2. Returning agricultural land to natural wetlands 3. Building new dams on the Mississippi River 4. Leaving crop residue on the land to reduce soil erosion and run-off

1. Elevating homes above flood level 2. Returning agricultural land to natural wetlands 4. Leaving crop residue on the land to reduce soil erosion and run-off

Select all the engineering systems or structures mentioned in the video that were put in place in New Orleans to deal with potential flooding. 1. Levees 2. Flood walls 3. Pumps 4. Drainage canals 5. Dams 6. Runoff collection ponds

1. Levees 2. Flood walls 3. Pumps 4. Drainage canals

Select all the things that can occur BEFORE a catastrophic landslide. 1. extensional cracks near the top of a slope 2. slumping of soils and sediments on a slope 3. liquifaction 4. small landslides

1. extensional cracks near the top of a slope 2. slumping of soils and sediments on a slope 4. small landslides

Select all the factors that contributed to the destabilization of the slope and led to the 2014 landslide. 1. higher than average precipitation 2. undercutting of the slope by the Stillaguamish River 3. slope composed of glacial sediments with high porosity 4. construction of housing development on top of the slope

1. higher than average precipitation 2. undercutting of the slope by the Stillaguamish River 3. slope composed of glacial sediments with high porosity

What was (were) the cause(s) of the La Conchita mudslides of 1995 and 2005?

1. oversteepening of the slope during construction of the road 2. removal of the toe material during development of the town at the base of the slope. 3. heavy winter rains.

Increases in precipitation lead to increased landslide risk. On average, how many landslide-related deaths occur in Nepal during each monsoon season?

100

The October 1963 Vajont Dam landslide killed around 2,500 people. How long did it take for the mass movement to flow out of the reservoir, over the dam, and into the valley below?

12 minutes

Approximately when did the rapid increase in human-produced atmospheric CO2 begin?

1700s

​The Intergovernmental Panel on Climate Change (IPCC) in 2014 estimated that Earth's average surface temperature would likely rise by how much above preindustrial levels by 2050?

2 degrees Celsius

All the engineering structures below are used to alter or slow coastal wave erosion except... 1. seawall 2. levee 3. groin 4. jetty

2. levee

Which of the following does NOT affect the amount of runoff from a precipitation event? 1. rate of precipitation 2. porosity and permeability of the land surface 3. shape of the stream 4. ground surface slope

3. shape of the stream

How long before a flood can someone purchase insurance from the National Flood Insurance program?

30 days

An unusually wet summer was the primary cause of the 1993 Flood. The jet stream became locked over the midwest and ____ inches of rain fell over ____ months.

30, 6

What makes Houston susceptible to flooding? 1. More frequent, intense rainfall events 2. Development/urbanization that increases runoff 3. Houston is located in a coastal and subtropical portion of Texas 4. All the above

4. All of the above

As of 2017, what is the approximate CO2 level in Earth's atmosphere?

400 ppm

According to the video, how many people died in the Oso Landslide?

43

How many states in the United States are affected by landslides

50

During the 1993 flood, Quincey, Illinois experienced flooding at the ________ recurrence interval.

500 year

What is the elevation of the city of New Orleans?

7-10 feet below sea level

How many states were directly affected by the 1993 Flood?

9

Which town's levee failure was credited with saving St Louis, Missouri from flooding.

Columbia, IL

Due to the force of the water that hit the Vajont Dam, the dam itself sustained severe damage.

False

The October 1963 Vajont Dam landslide occurred without any warning.

False

Where in North America are sinkholes most prevalent and why?

Florida, because it is almost all limestone and has abundant groundwater

What was unique about the 2014 Oso Landslide?

Given the height of the slope, the slide debris traveled 5 times farther than it should have.

After the eye of Hurricane Katrina passed over New Orleans, why did the flood waters continue to rise in the low-lying areas of the city?

Levee along two canals failed and water from Lake Ponchartrain drained into the city center.

Which town's levee withstood the flood?

Prairie du Rocher, IL

An unstable marine sediment with a disorganized structure that can flow like water if disturbed is called _________.

Quick Clay

What causes caverns or open spaces to form in limestone?

Rainwater mixes with carbon dioxide to make weak carbonic acid that dissolves limestone.

Besides wind, what is the biggest hazard from hurricanes?

Storm surges

What caused the Industrial Canal & Intercoastal Waterway levees to fail?

The storm surge sent a huge wave of water up the Intercoastal Waterway, over-topping the canal walls and scouring away the earthen levees.

Why would a home built on the floodplain behind a levee be safe from flooding?

This statement is not true

Major eruptions of volcanoes emit large amounts of CO2 and CH4, but their total contribution to atmospheric carbon levels is small.

True

Why did the 17th Street and London Street canals fail?

Water soaked into the underlying peat layer and weakened the soft sediments beneath the levee wall.

Beach nourishment _______________.

a coastal engineering method that replenishes the sand to provide a recreation beach and helps protect coastal properties from erosion by widening the beach

Like all hurricanes in the Atlantic Ocean, Hurricane Katrina began as _____.

a storm off the west coast of Africa

Which does NOT control the characteristics or shape of a coastline a. the power of the waves b. the durability (strength) of the rocks and sediments c. dominant wind direction d. sea level

c. dominant wind direction

Streams receive water from 2 primary sources:

runoff and groundwater

Why does a delta form when a river meets the ocean? a. Stream flow rate decreases as the stream reaches its base level b. Sediment is deposited at the mouth of the river c. Deposition exceeds coastline erosion d. All of the above

d. All the above

On average, more people die from which type of natural disaster than any other?

flash floods and flooding

What aspect of tropical cyclones tends to cause the greatest death and destruction

flooding from rain, waves, and storm surge

How might global warming exacerbate coastal hazards?

global warming is accompanied by sea level rise

What is the major driving force in all mass movements?

gravity

What is the primary cause of landslides

gravity exceeds strength of the slope

What keeps a stream flowing year-round, even though it may not rain for many months?

groundwater seepage from the adjacent ground into the stream

Using LIDAR mapping and carbon dating, geologists found evidence that Oso_______.

had a history of landslides

Over the last 30 years, hurricanes have become more ______ due to _______.

intense, warmer ocean temperatures

When pore spaces in sediment becomes saturated with water, the sediment loses strength and cohesion. This phenomenon is called __________.

liquifaction

​Greenhouse gases include all of the following...

methane nitrous oxide carbon dioxide chlorofluorocarbons

Why are the impacts of coastal hazards such as erosion, storm surge, and flooding so great?

because densely populated areas are located at or near the coasts

In what way can the construction of dams and levees INCREASE flood damage (both loss of property and life) on a floodplain?

by giving a false sense of security that encourages building and living on the floodplain

The gradual process of subsidence can result from all of the following activities except... A.pumping and removing groundwater to irrigate crops B.digging open-pit mines to mine for coal C.pumping and removing oil from an oil well D.draining a wetland, allowing the organic-rich soil to decompose

B.digging open-pit mines to mine for coal

Which agency manages the rivers, dams, and levees in the United States?

Army Corps of Engineers

If a 100-year flood occurred this year, when is the next 100-year flood possible?

anytime

Based upon knowledge of landslide physics, where did geologists direct rescue workers to search for survivors?

At the distal edge of the slide

The wetlands surrounding New Orleans are rapidly disappearing. Why?

- The wetlands surrounding New Orleans are being destroyed by ocean saltwater. - Man-made levees do not allow the Mississippi River to flood, starving the wetlands of sediments.

Select the 3 ENGINEERING flood-control methods. A. floodplain management through zoning regulations B. dams C. levees D. channelization

B. dams C. levees D. channelization

Rapid global warming may result in all the changes listed below except... A. increase in global average temperatures B. migration of people to coastal areas C. sea level rise D. increase in human and plant pests and disease

B. migration of people to coastal areas

Which of the following is true with respect to the underlying geology in the Vajont River valley? A. The Vajont River valley is underlain by rocks that dip (tilt) into the valley. B. The rocks in the Vajont River valley are mostly unconsolidated and susceptible to liquefaction during earthquakes. C. The Vajont River valley is underlain by rocks that dip (tilt) away from the valley. D. The Vajont River valley is underlain by a fault. Movement along this fault during a minor earthquake caused the October 1963 landslide, but the high water pressure in the rocks enhanced the effect of the shaking, causing a larger area to slide off the slope.

A. The Vajont River valley is underlain by rocks that dip (tilt) into the valley.

Using the accompanying diagram, label the features correctly.

A: main scarp, B: toe, C: crown, D: head

In the days preceding Hurricane Katrina, many people decide to stay in New Orleans even though they were instructed to evacuate. Why did some people stay in the city? (select all the reasons given in the video) a. They were elderly or sick b. They did not have transportation c. They did not receive a warning that a hurricane was approaching. d. They had survived previous hurricanes without evacuating.

a. They were elderly or sick b. They did not have transportation d. They had survived previous hurricanes without evacuating.

Which of the following is NOT a common reason cited for building large dams on rivers? a. flood control b. hydroelectric power c. to raise groundwater levels d. recreation

c. to raise groundwater levels

Which gas is thought to have the greatest effect on global warming or increasing global temperatures?

carbon dioxide

​CO2 reacts with water to form _______________, which makes the ocean more acidic.

carbonic acid