Geology Final Exam Chapter 16

Match the type of flood with the correct definition 1. frozen material creates a temporary dam on a thawing river. 2. artificial containment structures fail 3. seasonal floods 4. floods with high precipitation in a short time - flash floods - ice-jam floods - regional floods - dam-failure floods

1. ice-jam floods 2. dam-failure floods 3. regional floods 4. flash floods

1. A(n) --------- --------- is a bend in a steep narrow bedrock valley. 2. The lowest level to which a stream can erode is called ------- -------. 3. A(n) --------- is the remnant of a former floodplain. 4. Examples of local base level include a stream or a(n) ------. 5. A sweeping bend of a stream which is migrating laterally in a wide, flat valley is called a(n) ----------. 6. The flat, broad area surrounding a stream is referred to as a(n) ------------.

1. incised meander 2. base level 3. terrace 4. lake 5. meander 6. floodplain

What is infiltration? A. Water soaking into the ground B. The transition from liquid to gas as a result of increases in temperature C. Plants taking in water D. Water running off the surface and entering a channel

A.

drainage pattern that develops on isolated volcanic cones or domes

Radial

what are the four main types of drainage patterns?

Rectangular, Trellis, dendritic, radial

drainage pattern that develops in areas of alternating weak resistant bedrock

Trellis

Point bars are locations where deposition occurs whereas cutbanks are locations where erosion occurs. - True - False

True

How does an alluvial fan form?

When a stream with a steep gradient emerges onto a relatively flat lowland, its gradient drops, and it deposits a large portion of its sediment load in a pattern that looks like a fan from above.

The volume of water flowing past a certain point in a given amount of time is a river's --------

discharge

The geographical area where all surface water converges to one location is called its ------- --------

drainage basin

Running water is the second most important erosional agent sculpting Earth's land surface. - True - False

false

A river with a well-developed ----------- has a flat low-lying channel and experiences flooding during periods of high discharge.

floodplain

The ------------- of a river have a steep gradient, high channel roughness, and low water volume.

headwaters

A stream with a low to moderate gradient, carrying most of its load in suspension, should be characterized by many curves and bends called ---------.

meanders

A delta forms at the ------ of a river, where the velocity of the water flow decreases and deposition is highest.

mouth

drainage pattern that develops on highly jointed bedrock

rectangular

In what ways does a stream transport its load, and which part of the load moves most slowly? Select all that apply. - as a bed load, which is the slowest mode of particle transport in streams - as a suspended load - as a dissolved load, which is the slowest mode of particle transport in streams - as a suspended load, which is the slowest mode of particle transport in streams - as a dissolved load

- as a bed load, which is the slowest mode of particle transport in streams - as a suspended load - as a dissolved load

According to the hydrologic cycle, once precipitation has fallen on land, what paths might the water directly take? Select all that apply. - evaporation from the sea - evaporation/transpiration - runoff into the sea - runoff into a river - infiltration into the ground

- evaporation/transpiration - runoff into the sea - runoff into a river - infiltration into the ground

Which of the following is a characteristic of a graded stream? CHOOSE ALL THAT APPLY. - meanders - well-developed floodplain - v-shaped valley - waterfalls - rapids

- meanders - well-developed floodplain

Which of the following are part of the bed load? CHOOSE ALL THAT APPLY. - clay - sand - gravel - ions

- sand - gravel

How does an oxbow lake form? A. An oxbow lake forms when the bend of a meandering river is isolated from the river because erosional forces create a cutoff in the main river channel. This isolated bend becomes the oxbow lake. B. An oxbow lake forms when a meandering river connects to a previously empty sinkhole in the ground. C. An oxbow lake forms when a meander of a river greatly widens, becoming a lake that exists along the river. D. An oxbow lake forms when the flow velocity of a river slows to the point where sediment is deposited before and after a meander, cutting it off from the rest of the river. E. An oxbow lake forms when the river channels carve a more efficient path through the bedrock, abandoning the meander.

A

How might a stream channel become braided? A. If a large portion of a stream's sediment load consists of coarse material and the stream has a highly variable discharge, a stream channel can become braided. B. If a large portion of a stream's sediment load consists of dissolved material and the stream has a highly variable discharge, a stream channel can become braided. C. If a large portion of a stream's sediment load consists of coarse material and the stream has a consistently high discharge, a stream channel can become braided. D. If a large portion of a stream's sediment load consists of dissolved material and the stream has a consistently high discharge, a stream channel can become braided. E. If a large portion of a stream's sediment load consists of coarse material and the stream has a consistently low discharge, a stream channel can become braided.

A

If the velocity of a stream decreases, competence __________ and sediment is _____. A. decreases, deposited B. remains constant, deposited C. increases, deposited D. increases, eroded E. decreases, eroded

A

What are the three types of loads carried by streams? A. bed load, suspended load, dissolved load B. bed load, bouncing load, suspended load C. bed load, sliding load, rolling load D. sliding load, rolling load, bouncing load E. bed load, bouncing load, dissolved load

A

What is base level? A. The downward limit of erosion. B. The transition from a straight channel stream to a meandering stream. C. The highest elevation streams can be found. D. The gradient line along the longitudinal profile of the stream.

A

What is meant by a nonstructural approach to flood control? A. limiting certain activities or land uses and implementing appropriate zoning regulations in high-risk flood areas B. planting trees and foliage along the banks of streams and rivers with a known history of flooding C. waiting for problematic stream channels to alter themselves over time into more stable configurations D. waiting for streams and rivers to build natural levees on their own E. creating an artificial lake connected to a stream with a known history of floods to give floodwaters a place to go

A

Where are bedrock channels more likely to be found? A. Bedrock channels are typically found in the headwaters of river systems where streams have steep slopes. B. Bedrock channels are typically found in the headwaters of river systems where streams have shallow slopes. C. Bedrock channels are typically found throughout the entire lengths of river systems. D. Bedrock channels are typically found in the mouths of river systems where streams have shallow slopes. E. Bedrock channels are typically found in the mouths of river systems where streams have steep slopes.

A

Briefly describe a general drainage basin

An area drained by a stream is called a drainage basin, which is bounded by an imaginary line called a divide. The divide can be clearly visible as a sharp ridge, or it could be difficult to determine in subdued topography.

About what percentage of Earth's water is in the form of seawater? A. 6297% B. 97% C. 2% D. 71%

B

Which of the choices below correctly defines base level and differentiates between ultimate base level and local (temporary) base level? A. Base level is generally defined as the lowest depth that the water within a stream can reach. The ultimate base level is sea level; local base levels are lakes, resistant layers of rock, and rivers that act as base levels for their tributaries. B. Base level is generally defined as the lowest elevation to which a stream can erode its channel. The ultimate base level is sea level; local base levels are lakes, resistant layers of rock, and rivers that act as base levels for their tributaries. C. Base level is generally defined as the lowest elevation to which a stream can erode its channel. The ultimate base level is sea level; local base levels are the levels of groundwater in the area. D. Base level is generally defined as the lowest elevation to which a stream can erode its channel. The ultimate base level is the bottom of Earth's crust; local base levels are lakes, resistant layers of rock, and rivers that act as base levels for their tributaries. E. Base level is generally defined as the elevation of the streambed before it erodes lower into bedrock. The ultimate base level is sea level; local base levels are lakes, resistant layers of rock, and rivers that act as base levels for their tributaries.

B

Why are urban areas susceptible to flash floods? A. Oil, gasoline, and other auto fluids repel more water into the stream system B. A high percentage of the surface area is covered with cement, asphalt, and other impervious materials C. City sewers promote flooding of city streets and parking areas D. Construction materials promote rapid absorption of precipitation, which puts excess water into the stream system

B

________ are flat areas along streams that are created by the deposition of alluvium and is subject to periodic inundation. A. Riffles B. Floodplains C. Bars D. Terraces

B

What are the three main zones of a river system from highest to lowest? A. zone of transportation, zone of sediment production, and zone of deposition B. zone of sediment production, zone of deposition, and zone of transportation C. zone of sediment production, zone of transportation, and zone of deposition D. zone of deposition, zone of transportation, and zone of sediment production E. zone of deposition, zone of sediment production, and zone of transportation

C

What is suspended load? A. the ions that travel in the water column above the stream bed B. the ions that travel along stream bed C. the fine-grained particles that travel in the water column above the stream bed D. the fine-grained particles that travel along the stream bed

C

Which of the choices below is not a factor that causes infiltration and runoff to vary from place to place and from time to time? A. the extent and type of vegetation B. the duration and intensity of rainfall C. time of the day D. the slope of the land E. the nature of the surface material

C

Why doesn't sea level drop even though oceans have a higher rate of evaporation than precipitation? A. The continents subside at the same rate as water is depleted from the oceans, thus maintaining relative sea levels. B. Enough groundwater infiltrates into the oceans yearly to close the gap between water loss and water gain in the oceans. C. Surface water running off into the oceans makes up the difference between evaporation from the oceans and precipitation into the oceans, creating a balance. D. The meltwater from warming glaciers enters the oceans directly, closing the difference between water loss and gain in the oceans. E. The deficit of 36,000 cubic kilometers of water lost from the oceans yearly is not significant enough to affect the overall sea level.

C

How does the formation of a natural levee impact flooding? A. Natural levees lower the height of the stream channel, increasing the amount of flooding that will occur on the floodplain. B. Natural levees raise the height of the stream channel, increasing the amount of flooding that will occur on the floodplain. C. Natural levees lower the height of the stream channel, reducing the amount of flooding that will occur on the floodplain. D. Natural levees raise the height of the stream channel, reducing the amount of flooding that will occur on the floodplain.

D

Incised meanders and terraces are __________. A. created by a rise in base level B. formed by a graded stream C. examples of local base level D. erosional features E. depositional features

D

What is a natural levee A. a ridge of flood deposits far from a river channel B. a plain of flood deposits next to a river channel C. a ridge of flood deposits at the mouth of a river channel D. a ridge of flood deposits next to a river channel

D

Which of the following scenarios represents the best nonstructural approach to flood control? A. Paving the floodplain to increase the velocity of floodwaters B. Creating a series of dams and reservoirs to store floodwater and release it slowly over time C. Building an artificial levee 2 feet taller than the highest recorded flood D. Managing a floodplain to limit development in sensitive areas

D

drainage pattern that develops on relatively uniform surface materials

Dendritic

How can pieces of rock in contact with a stream bed move? A. bouncing, sliding, dissolution B. rolling, sliding, dissolution C. rolling, sliding, suspension D. bouncing, suspension, twisting E. rolling, sliding, bouncing

E

In general, how do the channel width, channel depth, flow velocity, and discharge change between the headwaters and the mouth of the stream? A. The channel width, channel depth, flow velocity, and discharge all decrease as the stream approaches the mouth. B. The channel width, channel depth, and flow velocity increase as the stream approaches the mouth, whereas the discharge decreases. C. The channel width and depth decrease as the stream approaches the mouth, whereas the water's flow velocity and increase decrease. D. The channel width and depth increase as the stream approaches the mouth, whereas the water's flow velocity and discharge decrease. E. The channel width, channel depth, flow velocity, and discharge all increase as the stream approaches the mouth.

E

Transpiration moves water from _______. A. the hydrosphere to the biosphere B. the atmosphere to the biosphere C. the hydrosphere to the atmosphere D. the geosphere to the hydrosphere E. the biosphere to the atmosphere

E

Velocity and turbulence are _____ at the __________. A. greatest; point bar B. greatest; inside of a meander C. weakest; cut bank D. equal; inside and outside of a meander E. greatest; outside of a meander

E

What is a flood plain? A. A flat surface below a river channel B. A flat surface above a river channel C. a wavy surface next to a river channel D. a wavy surface above a river channel E. a flat surface next to a river channel

E

What is a stream's longitudinal profile? A. the length of the stream divided by the vertical difference between the headwaters and the mouth B. an overhead view of the entire length of a stream C. a cross-sectional view of the width of the stream D. the angle of the slope along the entire stream E. a cross-sectional view of a stream from the headwaters to its mouth

E

Which of the following statements are true? A. A cut bank is located on the inside of a meander bend. B. Deposition is the dominant process at the cut bank. C. Neither erosion nor deposition is occurring at the cut bank. D. A cut bank forms when a meander is cut off from the main channel. E. A cut bank is located on the outside of a meander bend.

E