Deck 18: Stream Transport: From Mountains to Oceans

Question 1

The long dimension of a ripple forms ________ to the current direction.

A)parallel
B)at a 45 $\degree$ angle
C)at a 60 $\degree$ angle
D)perpendicular

Answer 1

perpendicular

Question 2

Which of the following flows is most likely to be turbulent?

A)slow flow in a shallow channel
B)slow flow in a deep channel
C)fast flow in a shallow channel
D)fast flow in a deep channel

Answer 2

D

Question 3

Curves and bends in a stream channel are called

A)alluvial fans.
B)braids.
C)deltas.
D)meanders.

Answer 3

D

Question 4

Sand grains will not be transported by a stream unless the stream velocity exceeds

A)2 centimeters per second.
B)2 meters per second.
C)20 centimeters per second.
D)20 meters per second.

Question 5

Which of the following materials is most likely to be transported as suspended load?

A)boulders
B)clay
C)gravel
D)sand

Question 6

Suspended load includes all material

A)rolling along the bottom of the stream.
B)temporarily or permanently suspended in the flow.
C)deposited on the bottom of the stream.
D)rolling along the bottom and suspended in the flow.

Question 7

As the velocity of a stream current increases,

A)more of the bed material is in motion.
B)progressively finer particles are suspended.
C)the suspended load decreases.
D)total capacity decreases.

Question 8

Which of the following particles is the most easily eroded from the bed of a stream?

A)boulders
B)cohesive clay
C)pebbles
D)sand

Question 9

Because of human activity,sediment transported by streams has

A)decreased dramatically.
B)remained constant.
C)increased dramatically.
D)decreased by a minor amount.

Question 10

Which of the following terms describes the total sediment load carried by a stream?

A)capacity
B)competence
C)discharge
D)viscosity

Question 11

Which of the following statements about streams is false?

A)Faster currents can carry larger particles than slower currents.
B)Laminar flows generally carry more sediment than turbulent flows.
C)Smaller particles settle more slowly than larger particles.
D)The base level is the lowest level to which a stream can erode.

Question 12

Which of the following is a measure of a fluid's resistance to flow?

A)capacity
B)competence
C)permeability
D)viscosity

Question 13

The word _____ is used for any flowing body of water,large or small.

A)river
B)stream
C)channel
D)drainage

Question 14

Which of the following correctly lists the order of bed forms that develop with increasing current velocity?

A)dunes,ripples,flat beds
B)ripples,dunes,flat beds
C)flat beds,dunes,ripples
D)ripples,flat beds,dunes

Question 15

Which of the following statements about fluid flow is false?

A)As the velocity of a stream increases,laminar flow may change to turbulent flow.
B)The viscosity of most fluids increases as temperature increases.
C)Most streams and rivers are turbulent.
D)The more viscous the fluid,the more likely the flow is laminar.

Question 16

Which of the following is considered part of a stream's bed load?

A)dissolved salts
B)saltating sand grains
C)gravel sliding along the bottom
D)suspended clay particles

Question 17

Which of the following sets of conditions would favor turbulent flow as opposed to laminar flow?

A)high fluid viscosity and high flow velocity
B)high fluid viscosity and low flow velocity
C)low fluid viscosity and high flow velocity
D)low fluid viscosity and low flow velocity

Question 18

During turbulent flow,smaller grains will not

A)be picked up more frequently than large grains.
B)jump higher than large grains.
C)settle more quickly than large grains.
D)travel farther than large grains.

Question 19

In a sand dune in a river,_________ occurs on the upstream side of the dune and ___________ occurs on the downstream side of the dune.

A)deposition; deposition
B)erosion; deposition
C)deposition; erosion
D)erosion; erosion

Question 20

Which of the following terms describes a curved,coarse-grained deposit that forms on the inside curve of a stream?

A)dune
B)meander
C)oxbow
D)point bar

Question 21

Which of the following depositional settings consists primarily of fine-grained silt and mud?

A)stream channels
B)floodplains
C)natural levees
D)point bars

Question 22

If a dam is built,sediment will __________ on the upstream side of the dam and sediment will ___________ on the downstream side of the dam.

A)accumulate; accumulate
B)erode; accumulate
C)accumulate; erode
D)erode; erode

Question 23

Large,cone-shaped deposits of sediment at a mountain front are called

A)alluvial fans.
B)deltas.
C)natural levees.
D)terraces.

Question 24

What are the dimensions (units)of stream discharge?

A)cubic meters
B)square meters per second
C)meters per second
D)cubic meters per second

Question 25

What is the primary reason sediment is deposited in large cone-shaped deposits at mountain fronts?

A)because stream valleys widen abruptly at a mountain front
B)because stream valleys narrow abruptly at a mountain front
C)because stream valleys get much steeper at a mountain front
D)because stream valleys get less steep at a mountain front

Question 26

Which of the following would be the most fertile area for crops?

A)a stream channel
B)a floodplain
C)a natural levee
D)an uplands area away from the stream

Question 27

Which of the following equations for stream discharge is correct?

A)discharge = length × velocity
B)discharge = depth × velocity
C)discharge = width × depth × velocity
D)discharge = volume × velocity × distance

Question 28

At a bend in a river,______ occurs on the outside of the bend and ______ occurs on the inside of the bend.

A)deposition; deposition
B)erosion; deposition
C)deposition; erosion
D)erosion; erosion

Question 29

The volume of water flowing past a given point in a given time is called the

A)capacity.
B)competence.
C)discharge.
D)viscosity.

Question 30

At any point in a river,the equilibrium between erosion of the streambed and sedimentation in the channel is controlled by

A)climate.
B)stream flow.
C)topography.
D)climate,stream flow,and topography.

Question 31

Which of the following statements regarding graded streams is true?

A)Coarse-grained sediments accumulate at the mouth of the stream; finer-grained sediments are deposited at the head of the stream.
B)The discharge is constant from the head of the stream to the mouth.
C)The slope of the stream is constant from head to mouth.
D)There is a balance between erosion and sedimentation.

Question 32

For a given river,which of the following floods would have the largest discharge?

A)a 5-year flood
B)a 20-year flood
C)a 100-year flood
D)Impossible to tell from the information provided.

Question 33

What is the velocity of stream that is two meters wide,one meter deep,and has a discharge of 10 m³/sec?

A)1 m/s
B)2 m/s
C)5 m/s
D)10 m/s

Question 34

Which of the following statements regarding stream terraces is true?

A)Terraces are composed of bedrock and form as a result of rapid subsidence.
B)Terraces are composed of bedrock and form as a result of rapid uplift.
C)Terraces are composed of floodplain deposits and form as a result of rapid subsidence.
D)Terraces are composed of floodplain deposits and form as a result of rapid uplift.

Question 35

Which of the following describes the shape of the longitudinal profile of a stream?

A)a concave downward curve
B)a horizontal line
C)a concave upward curve
D)a straight line sloping downstream

Question 36

Which of the following statements regarding floods is true?

A)A 50-year flood has a 2% chance of occurring in any one year.
B)A 50-year flood is generally larger than a 100-year flood.
C)A 50-year flood occurs more frequently than a 5-year flood.
D)A 50-year flood on one river is the same size as a 50-year flood on another river.

Question 37

Oxbow lakes are associated with which of the following types of rivers?

A)braided rivers
B)dendritic rivers
C)meandering rivers
D)straight rivers

Question 38

In which of the following locations would one most likely find a braided stream?

A)at the edge of a melting glacier
B)on a gently sloping plain of fine-grained sediment
C)in a narrow gorge cut into bedrock
D)in/on all of the above

Question 39

In an alluvial fan,the coarsest material would be deposited

A)on the steep,upper slopes of the fan.
B)on the gentle,lower slopes of the fan.
C)approximately halfway between the steep slopes of the mountains and the gentle slopes of the plains.
D)where two fans interfere or overlap each other.

Question 40

For most rivers,discharge __________ downstream.

A)increases
B)remains constant
C)decreases slightly
D)decreases greatly

Question 41

Discharge is expressed in units of

A)m)
B)m/sec.
C)m²/sec.
D)m³/sec.

Question 42

Stream terraces are made up of ___________ deposits.

A)point bar sand
B)floodplain
C)alluvial gravel
D)dune migration

Question 43

A stream that existed before the present day topography was created is a(n)______ stream.

A)superposed
B)dendritic
C)antecedent
D)preformational

Question 44

The process whereby streams break apart and erode rock is called

A)abrasion.
B)discharge.
C)superposition.
D)transport.

Question 45

In North America,the continental divide that separates water that flows into the Atlantic Ocean from water that flows into the Pacific Ocean is located

A)in the Sierra Nevada,California.
B)in the Rocky Mountains.
C)in the Appalachian Mountains.
D)along the Mississippi River.

Question 46

Where do deltas form?

A)at drainage divides
B)at mountain fronts
C)at meander loops
D)at river mouths

Question 47

The ____________ dictate(s)a drainage pattern.

A)lithology of the underlying bedrock units.
B)geologic structures in the bedrock units.
C)shape of the land surface.
D)lithology of the underlying bedrock units,geologic structures in the bedrock units,and the shape of the land surface.

Question 48

On a delta,smaller rivers that branch off downstream are called

A)distributaries.
B)divides.
C)rivulets.
D)tributaries.

Question 49

Which of the following best explains why there are no large deltas on the east coast of North America?

A)because no rivers empty out along the east coast of North America
B)because the Appalachian Mountains are too resistant to erosion
C)because the rivers of the east coast have currents that are too weak to carry much sediment
D)because the waves and tides in the Atlantic Ocean are too strong

Question 50

________ is the process whereby sand grains jump along the streambed during transport.

A)Superposition
B)Hydrolysis
C)Saltation
D)Meandering

Question 51

Because of the undercutting action,waterfalls

A)retreat downstream.
B)grow shorter over time.
C)grow taller over time.
D)retreat upstream.

Question 52

Why is the Mississippi delta so large?

A)because the Mississippi River transports a huge amount of sediment
B)because tides in the Gulf of Mexico are not very strong
C)because waves in the Gulf of Mexico are not very strong
D)all of the above

Question 53

Why are sand-sized particles easier to erode than clay-sized particles?

A)because sand grains are rounder and roll more easily,whereas clay particles are flat and platy
B)because sand grains are typically made of quartz,which saltates more easily than clay particles
C)because clay particles are denser than sand particles,making them heavier
D)because clay particles are attracted to tone another because of opposite charges,which hold them in place

Question 54

Which of the following beds in a delta consists of the coarsest sediment?

A)bottomset beds
B)foreset beds
C)topset beds
D)All of the above contain similar amounts of coarse sediment.

Question 55

Where does a stream channel begin?

A)where rainwater infiltrates into the subsurface weakening the underlying bedrock
B)where there are active faults that create cracks in the underlying bedrock
C)where rainwater flows over the surface so fast that it carves into the underlying units
D)where there are pre-existing weaknesses in the bedding planes in the underlying units

Question 56

Which of the following lakes is the world's largest and deepest?

A)Great Salt Lake,North America
B)Lake Superior,North America
C)Lake Baikal,Asia
D)Lake Victoria,Africa

Question 57

How far can large rivers,such as the Amazon,maintain a current out to sea?

A)meters
B)tens of meters
C)hundreds of meters
D)many kilometers

Question 58

What type of drainage network would you expect to find on a volcano?

A)dendritic drainage
B)rectangular drainage
C)radial drainage
D)trellis drainage

Question 59

The topographic rise between two streams is called a

A)divide.
B)point bar.
C)trellis.
D)valley.

Question 60

The factor(s)that dictate(s)whether water in a stream channel undergoes turbulent or laminar flow is(are)

A)the velocity of the water.
B)the geometry of the stream channel.
C)the viscosity of the water.
D)the velocity of the water,the geometry of the stream channel,and the viscosity of the water.

Question 61

The Niagara Falls are being cut back approximately

A)10 km per year.
B)100 m per year.
C)10 m per year.
D)1 m per year.

Question 62

An imaginary line below which a stream cannot erode is called

A)ground level.
B)sea level.
C)lake level.
D)base level.

Question 63

A river widens while maintaining constant slope and depth.How would the velocity and discharge change?

A)velocity decreases,discharge increases
B)velocity increases,discharge decreases
C)velocity remains constant,discharge remains constant
D)velocity decreases,discharge remains constant

Question 64

All else being equal,high viscosity fluids should flow ______ with _____ streamlines in comparison with low viscosity fluids.

A)slower; straight
B)slower; crossing
C)faster; straight
D)faster; crossing

Question 65

A stream that has a smoothly curving longitudinal profile representing a balance between erosion and sedimentation is referred to as a __________ stream.

A)standing
B)base level
C)equilibrium
D)graded

Question 66

A tree-like drainage pattern is known as

A)dendritic.
B)radial.
C)rectangular.
D)trellis.

Question 67

What sort of sedimentary structure forms where rivers run into bodies of standing water?

A)alluvial fan
B)delta
C)terrace
D)floodplain

Question 68

A drainage divide is

A)a fork in the river.
B)a topographic high that separates stream systems.
C)a ridge between gullies.
D)a piece of land between tributaries.

Question 69

Potholes in bedrock of riverbeds form by

A)abrasion.
B)undercutting.
C)chemical and physical weathering.
D)sedimentation.

Question 70

Which of the following situations,for a fluid,is most likely to generate crossing streamlines?

A)low viscosity,high flow rate
B)high viscosity,high flow rate
C)low viscosity,low flow rate
D)low viscosity,low flow rate

Question 71

What is the discharge of a stream that is one meter deep,two meters wide,and has a water flow of 5 meters per second?

A)1 m/sec
B)5 m/sec
C)5 m³/sec
D)10 m³/sec

Question 72

An antident stream is

A)controlled by the current topography.
B)always predated by the current topography.
C)a type of meandering river.
D)a kind of superposed stream.

Question 73

The nature of fluid flow (turbulent versus laminar)is independent of

A)fluid velocity.
B)fluid viscosity.
C)channel dimensions.
D)load.

Question 74

What sort of stream tends to stay with the pattern it developed initially and not change?

A)meandering
B)antident
C)braided
D)superposed

Question 75

Which of the following particles would have the lowest settling velocity?

A)sand
B)clay
C)gravel
D)cobbles

Question 76

What information do geologists use to estimate speeds of ancient rivers?

A)sediment type
B)grain size
C)channel dimensions
D)chemistry of the sediments

Question 77

What is the correct sequence of sedimentary layers in a delta (top to bottom)?

A)topset,middleset,bottomset
B)highset,middleset,lowset
C)topset,bar sand,foreset,bottomset
D)topset,foreset,bar sand,bottomset

Question 78

The process whereby streams progressively cut their channels upland is called

A)weathering.
B)pothole formation.
C)headward erosion.
D)undercutting.

Question 79

Where do rapids form in a river?

A)where the flow is slow
B)where the flow moderate
C)where the flow is fast
D)where the flow is very fast

Question 80

Which of the following flows is most likely to be turbulent?

A)slow flow in a shallow channel
B)slow flow in a deep channel
C)fast flow in a shallow channel
D)fast flow in a deep channel