Question 1

A debris flow can contain less than 40 percent sediment.

Accepted Answer

A) True 
 B)False  False

Question 2

Why do braided streams form in a dry climate instead of meandering streams?

Accepted Answer

A) The stream flows on a broad, flat surface, so it spreads out and braids. 
B) The stream has too little water to carry the total sediment supplied. 
C) The stream channel is so shallow that the stream flows easily over its banks. 
D) Water soaks down to the water table, so it doesn't ever flow downslope. 
E) There are so many channels that they can't help but cross one another to form a braided pattern. 
A) The stream flows on a broad, flat surface, so it spreads out and braids. 
B) The stream has too little water to carry the total sediment supplied. 
C) The stream channel is so shallow that the stream flows easily over its banks. 
D) Water soaks down to the water table, so it doesn't ever flow downslope. 
E) There are so many channels that they can't help but cross one another to form a braided pattern. B

Question 3

A river slope or gradient adjusts to what three factors that it has no control over?

Accepted Answer

A) stream width, depth, and amount of water 
B) water turbulence, channel roughness, and grain size of sediment 
C) water velocity, water temperature, and stream depth 
D) water velocity, grain size of sediment, and amount of sediment 
E) channel shape, channel cross section, and channel roughness 
A) stream width, depth, and amount of water 
B) water turbulence, channel roughness, and grain size of sediment 
C) water velocity, water temperature, and stream depth 
D) water velocity, grain size of sediment, and amount of sediment 
E) channel shape, channel cross section, and channel roughness D

Question 4

A glacial outburst flood typically originates from a lake.

Accepted Answer

A) True 
 B)False

Question 5

Why are the deposits of streams graded with the largest boulders or pebbles at the bottom?

Accepted Answer

A) The largest boulders are always at the bottom; they never move. 
B) The largest boulders eroded from the stream bank immediately roll to the bottom and stay there. 
C) Jostling of boulders, pebbles, and sand in turbulent water moves the boulders to the bottom. 
D) As the water slows after a flood, the largest boulders drop out first. 
E) Tributaries add additional sediment to the stream. 
A) The largest boulders are always at the bottom; they never move. 
B) The largest boulders eroded from the stream bank immediately roll to the bottom and stay there. 
C) Jostling of boulders, pebbles, and sand in turbulent water moves the boulders to the bottom. 
D) As the water slows after a flood, the largest boulders drop out first. 
E) Tributaries add additional sediment to the stream.

Question 6

Why are buried oil and gas pipelines vulnerable to damage during a flood?

Accepted Answer

A) The pipes rise with the rising water level, causing the pipes to break. 
B) The large amounts of sediment flowing during a flood puts additional pressure on the pipes. 
C) Channel scour can erode down to the pipeline level, and tumbling rocks can sever the pipe. 
D) When the levee is overtopped, the dropping water level can expose the pipe, leading to damage. 
E) If the oil and gas are shut off, the pipe becomes lighter and can float to the bankfull level. 
A) The pipes rise with the rising water level, causing the pipes to break. 
B) The large amounts of sediment flowing during a flood puts additional pressure on the pipes. 
C) Channel scour can erode down to the pipeline level, and tumbling rocks can sever the pipe. 
D) When the levee is overtopped, the dropping water level can expose the pipe, leading to damage. 
E) If the oil and gas are shut off, the pipe becomes lighter and can float to the bankfull level.

Question 7

A hyperconcentrated flow has between 20 and 47 percent sediment by volume. ​

Accepted Answer

A) True 
 B)False

Question 8

A(n) _______________ is able to maintain a dynamic equilibrium between inflow and outflow of sediment.

Accepted Answer

The answer of A(n) _______________ is able to maintain a...

Question 9

The volume of sediment a stream can carry is known as its _______________.

Accepted Answer

The answer of The volume of sediment a stream can...

Question 10

Instruments called _______________ more accurately approximate stream flow by measuring water velocity at hundreds of locations based on the shift in sound frequencies due to moving particles.

Accepted Answer

acoustic d

Question 11

Lahars carry volcanic material, making them different from mudflows of clay.

Accepted Answer

A) True 
 B)False

Question 12

Explain the relationship between stream velocity and erosion.

Accepted Answer

In general, a higher stream velocity ind

Question 13

A stream that is overloaded with sediment and forms broad, multichannel paths is called a(n) _______________ stream.

Accepted Answer

The answer of A stream that is overloaded with sediment...

Question 14

Stream discharge is calculated by multiplying the water's average velocity by the _______________ of the stream.

Accepted Answer

cross-sect

Question 15

If a side stream feeds coarse gravel into a river with a sandy bottom, what does the river do about it?

Accepted Answer

A) The river flushes it down into the valley. 
B) The slope of the riverbed builds up until it is steep enough to transport the size of gravel supplied, or until a flood carries it downstream. 
C) The gravel dams the river channel. 
D) The gravel works down through sediments in the riverbed until it reaches bedrock. 
E) The water slows down because the larger sediment gets in the way. 
A) The river flushes it down into the valley. 
B) The slope of the riverbed builds up until it is steep enough to transport the size of gravel supplied, or until a flood carries it downstream. 
C) The gravel dams the river channel. 
D) The gravel works down through sediments in the riverbed until it reaches bedrock. 
E) The water slows down because the larger sediment gets in the way.

Question 16

Which area is LEAST likely to have a flash flood?

Accepted Answer

A) western Washington state 
B) southern Arizona 
C) eastern Nevada 
D) southern Texas 
E) central South Dakota 
A) western Washington state 
B) southern Arizona 
C) eastern Nevada 
D) southern Texas 
E) central South Dakota

Question 17

Engineers commonly added rock rubble, or _______________, along the banks of a straightened portion of a stream.

Accepted Answer

The answer of Engineers commonly added rock rubble, or _______________,...

Question 18

What does NOT cause an area of rapids on a stream?

Accepted Answer

A) steepening of the channel slope 
B) bedrock in the stream channel 
C) the presence of a thalweg 
D) higher than normal water in the stream bed 
E) greater channel depth and water velocity 
A) steepening of the channel slope 
B) bedrock in the stream channel 
C) the presence of a thalweg 
D) higher than normal water in the stream bed 
E) greater channel depth and water velocity

Question 19

After a major rainstorm in a humid climate and with no overland flow to a stream, why does the stream level rise almost immediately?

Accepted Answer

A) Groundwater seeps down to raise the water table and forces older groundwater out into the stream. ​ 
B) The groundwater moves very fast, through porous ground, to the stream. 
C) The stream rise comes from farther up the drainage basin. 
D) Actually it doesn't rise rapidly; it merely seems like it does. 
E) The groundwater displaces older groundwater in the stream, over the water table. 
A) Groundwater seeps down to raise the water table and forces older groundwater out into the stream. ​ 
B) The groundwater moves very fast, through porous ground, to the stream. 
C) The stream rise comes from farther up the drainage basin. 
D) Actually it doesn't rise rapidly; it merely seems like it does. 
E) The groundwater displaces older groundwater in the stream, over the water table.

Question 20

A gaining stream is more likely to be found in a wet climate.

Accepted Answer

A) True 
 B)False

A debris flow can contain less than 40 percent sediment.

Why do braided streams form in a dry climate instead of meandering streams?

A river slope or gradient adjusts to what three factors that it has no control over?

A glacial outburst flood typically originates from a lake.

Why are the deposits of streams graded with the largest boulders or pebbles at the bottom?

Why are buried oil and gas pipelines vulnerable to damage during a flood?

A hyperconcentrated flow has between 20 and 47 percent sediment by volume.

A(n) _______________ is able to maintain a dynamic equilibrium between inflow and outflow of sediment.

The volume of sediment a stream can carry is known as its _______________.

Instruments called _______________ more accurately approximate stream flow by measuring water velocity at hundreds of locations based on the shift in sound frequencies due to moving particles.

Lahars carry volcanic material, making them different from mudflows of clay.

Explain the relationship between stream velocity and erosion.

A stream that is overloaded with sediment and forms broad, multichannel paths is called a(n) _______________ stream.

Stream discharge is calculated by multiplying the water's average velocity by the _______________ of the stream.

If a side stream feeds coarse gravel into a river with a sandy bottom, what does the river do about it?

Which area is LEAST likely to have a flash flood?

Engineers commonly added rock rubble, or _______________, along the banks of a straightened portion of a stream.

What does NOT cause an area of rapids on a stream?

After a major rainstorm in a humid climate and with no overland flow to a stream, why does the stream level rise almost immediately?

A gaining stream is more likely to be found in a wet climate.

Natural Hazards and Disasters

Plate Tectonics and Physical Hazards

Earthquakes and Their Causes

Earthquake Predictions Forecasts and Mitigation

Tsunami

Volcanoes Tectonic Environments and Eruptions

Volcanoes Hazards and Mitigation

Landslides and Other Downslope Movements

Sinkholes Land Subsidence and Swelling Soils

Weather Thunderstorms and Tornadoes

Climate Change Processes and History

Climate Change Impacts and Mitigation

Floods and Human Interactions

Waves Beaches and Coastal Erosion

Hurricanes and nor Easters

Wildfires

Asteroid and Comet Impacts

Filters

Exam 13: Streams and Flood Processes

A debris flow can contain less than 40 percent sediment.

Why do braided streams form in a dry climate instead of meandering streams?

A river slope or gradient adjusts to what three factors that it has no control over?

A glacial outburst flood typically originates from a lake.

Why are the deposits of streams graded with the largest boulders or pebbles at the bottom?

Why are buried oil and gas pipelines vulnerable to damage during a flood?

A hyperconcentrated flow has between 20 and 47 percent sediment by volume. ​

A(n) _______________ is able to maintain a dynamic equilibrium between inflow and outflow of sediment.

The volume of sediment a stream can carry is known as its _______________.

Instruments called _______________ more accurately approximate stream flow by measuring water velocity at hundreds of locations based on the shift in sound frequencies due to moving particles.

Lahars carry volcanic material, making them different from mudflows of clay.

Explain the relationship between stream velocity and erosion.

A stream that is overloaded with sediment and forms broad, multichannel paths is called a(n) _______________ stream.

Stream discharge is calculated by multiplying the water's average velocity by the _______________ of the stream.

If a side stream feeds coarse gravel into a river with a sandy bottom, what does the river do about it?

Which area is LEAST likely to have a flash flood?

Engineers commonly added rock rubble, or _______________, along the banks of a straightened portion of a stream.

What does NOT cause an area of rapids on a stream?

After a major rainstorm in a humid climate and with no overland flow to a stream, why does the stream level rise almost immediately?

A gaining stream is more likely to be found in a wet climate.

Natural Hazards and Disasters

Plate Tectonics and Physical Hazards

Earthquakes and Their Causes

Earthquake Predictions Forecasts and Mitigation

Tsunami

Volcanoes Tectonic Environments and Eruptions

Volcanoes Hazards and Mitigation

Landslides and Other Downslope Movements

Sinkholes Land Subsidence and Swelling Soils

Weather Thunderstorms and Tornadoes

Climate Change Processes and History

Climate Change Impacts and Mitigation

Floods and Human Interactions

Waves Beaches and Coastal Erosion

Hurricanes and nor Easters

Wildfires

Asteroid and Comet Impacts

Filters

A hyperconcentrated flow has between 20 and 47 percent sediment by volume.