Deck 14: River Systems

Question 1

Stream drainage patterns are determined by which of the following?

A)regional steepness and relief only
B)variations in rock resistance only
C)climate only
D)landscape characteristics only
E)climate,regional steepness and relief,landscape characteristics,and variations in rock resistance.

Answer 1

E

Question 2

Processes that are related expressly to streams and rivers are termed

A)fluvial.
B)geomorphic.
C)lentic.
D)lotic.
E)riverine.

Answer 2

A

Question 3

Overland flow can concentrate in small grooves called ,which can enlarge to form .

A)striations;potholes
B)potholes;striations
C)rills;gullies
D)gullies;rills
E)striations;gullies

Answer 3

C

Question 4

A basin in which water leaves via evapotranspiration or subsurface gravitational flow instead of reaching the ocean is said to have

A)disappearing streams.
B)hydraulic action.
C)base flow.
D)deranged patterns.
E)internal drainage.

Question 5

The general term for channelized water flow,regardless of size,is

A)river.
B)gully.
C)stream.
D)rill.
E)interfluve.

Question 6

The area of land from which all water in it drains into the same place is known as a(n)

A)interfluve.
B)watershed.
C)drainage divide.
D)fluvial unit.
E)hydrologic unit.

Question 7

This drainage pattern is characteristic of dipping or folded topography.

A)annular
B)trellis
C)radial
D)rectangular
E)dendritic

Question 8

Rectangular drainage patterns form primarily as a result of

A)differential resistance to erosion.
B)topographic uplift.
C)flow through anticlinal and synclinal topography.
D)flow through a faulted and jointed landscape.
E)hard,resistant rock that prevents erosion.

Question 9

Drainage density is determined by

A)dividing the number of streams in a basin by the basin area.
B)dividing the actual path length of a stream by the shortest path length of the stream.
C)averaging the discharge values across a drainage basin.
D)dividing the total length of all stream channels in the basin by the area of the basin.
E)averaging the channel depth of the streams in a drainage basin.

Question 10

A drainage divide that separates drainage basins that empty into different bodies of water surrounding a continent is known as

A)a catchment.
B)a delta.
C)a continental divide.
D)an interfluve.
E)a rill.

Question 11

What is the drainage density of a 100 mi2 drainage basin with 25 miles of stream,running through three rivers?

A)3
B)33.333
C)4 mi./mi.²
D)0.25 mi./mi.²
E)0.15 km/km²

Question 12

In stream formation,surface water initially moves down slope in a thin film called

A)river.
B)gully.
C)sheetflow.
D)rill.
E)interfluve.

Question 13

Drainage basins are

A)open systems.
B)closed systems.
C)equilibrium systems.
D)open systems in terms of energy,closed systems in terms of matter.
E)closed systems in terms of energy,open systems in terms of matter.

Question 14

Watersheds are defined by

A)continental divides.
B)drainage divides.
C)stream orders.
D)fluvial units.
E)stream size and density.

Question 15

The science of water and its global circulation,distribution,and properties is known as

A)geomorphology.
B)climatology.
C)lithology.
D)fluviology.
E)hydrology.

Question 16

The area of high ground that separates one valley from another and directs sheetflow is known as .

A)the maximum contour elevation
B)a drainage divide
C)an interfluve
D)the continental divide
E)rill

Question 17

This tree-like drainage pattern efficiently moves water and sediment through its system due to minimization of the total length of each branch.

A)dendritic
B)trellis
C)radial
D)deranged
E)rectangular

Question 18

Faulted and jointed landscapes direct stream courses in patterns of right-angle turns forming this drainage pattern.

A)radial
B)rectangular
C)trellis
D)dendritic
E)deranged

Question 19

This drainage pattern results when streams flow off a central peak or dome.

A)annular
B)trellis
C)radial
D)rectangular
E)deranged

Question 20

This drainage pattern is associated with steep slopes.

A)parallel
B)dendritic
C)trellis
D)deranged
E)radial

Question 21

streams have some groundwater input,but only flow for certain periods during a year.

A)Perennial
B)Intermittent
C)Ephemeral
D)Temporary
E)Exotic

Question 22

Hydraulic action is highest

A)near the surface in the middle of streams.
B)in areas with low discharge.
C)where flow is turbulent.
D)within deep and wide channels.
E)along slow moving currents.

Question 23

If a stream originates in a humid region,but subsequently flows through an arid region,discharge is likely highest

A)upstream.
B)downstream.
C)midstream.
D)at an estuary or confluence with another stream.
E)along tributaries.

Question 24

Erosion in which boulders and gravel moving along the channel break apart and as rocks and sediment grind and carve streambeds is known as

A)sheetflow.
B)saltation.
C)weathering.
D)abrasion.
E)hydraulic action.

Question 25

A drainage system that maintains its original course and pattern as it erodes into underlying horizontal beds of different structure than that in which the system evolved is called a(n)

A)deranged pattern.
B)discordant stream.
C)annular pattern.
D)yazoo stream.
E)superposed stream.

Question 26

This graph,showing the effects of urbanization on streamflow over time,is an example of a

A)water budget.
B)hydrograph.
C)climograph.
D)hydrological cycle.
E)cladogram.

Question 27

Turbulent flow is likely to be least in

A)channels with tree trunks and other obstacles.
B)shallow streams with boulders.
C)streams with high friction.
D)deep,lowland rivers.
E)along the rocky banks of a stream.

Question 28

In most river basins in humid regions,discharge is highest

A)upstream.
B)downstream.
C)midstream.
D)at the headwaters.
E)along tributaries.

Question 29

streams flow year-round,fed by snowmelt,rainfall,groundwater,or a combination thereof.

A)Perennial
B)Intermittent
C)Ephemeral
D)Permanent
E)Temporary

Question 30

The river with the greatest discharge is the

A)Ganges.
B)Mississippi.
C)Orinoco.
D)Yangtze.
E)Amazon.

Question 31

Erosion performed by flowing water alone is known as

A)sheetflow.
B)saltation.
C)weathering.
D)abrasion.
E)hydraulic action.

Question 32

Which of the following is used to measure streamflow?

A)current meter
B)barometer and sling psychrometer
C)statistical methods of probability
D)reservoirs
E)evaporimeters

Question 33

Which of the following landforms is incorrectly matched with a drainage pattern?

A)volcano - radial
B)folded mountain belt - trellis
C)faulted and jointed - rectangular
D)glaciated - deranged
E)topographically disrupted areas - parallel

Question 34

A stream's volume of flow per unit of time is its

A)speed.
B)velocity.
C)discharge.
D)flow rate.
E)base load.

Question 35

streams are not connected to groundwater systems and only flow after precipitation events.

A)Perennial
B)Intermittent
C)Ephemeral
D)Temporary
E)Exotic

Question 36

Which of the following lists of processes are in the correct sequence as to their occurrence in nature?

A)deposition,erosion,transport,weathering
B)weathering,erosion,deposition,transport
C)weathering,deposition,erosion,transport
D)weathering,erosion,transport,deposition
E)transport,deposition,erosion,weathering

Question 37

In a given section of channel,the greatest flow velocities are usually

A)near the surface,near the center.
B)along the shallowest portions of the stream.
C)along either bank.
D)near the bottom of the stream channel.
E)in areas with large obstacles,such as tree trunks and boulders.

Question 38

With no clear geometry and no true stream valley,this drainage pattern occurs in areas such as glaciated shield regions.

A)deranged
B)radial
C)parallel
D)dendritic
E)trellis

Question 39

As the discharge of a stream increases,which of the following also happens?

A)Stream channels narrow,become shallower,and lose velocity.
B)The rate of flow decreases.
C)Channel width increases but channel depth decreases.
D)Width,depth,and/or velocity increase.
E)Erosion and sediment transport are greatly reduced.

Question 40

streams begin in moist regions and flow downstream into arid landscapes with high evapotranspiration.

A)Perennial
B)Intermittent
C)Ephemeral
D)Temporary
E)Exotic

Question 41

The sediment load consisting of fine-grained clastic particles held aloft in the stream is the

A)bed load.
B)suspended load.
C)dissolved load.
D)flow load.
E)saltation.

Question 42

The main process contributing material in solution in sediment load is

A)physical weathering.
B)chemical weathering.
C)biological weathering.
D)erosion.
E)deposition.

Question 43

The sediment load consisting of coarse material too large to remain in suspension,moving along the channel bottom via traction and saltation is the

A)bed load.
B)suspended load.
C)dissolved load.
D)flow load.
E)free load.

Question 44

A(n)stream is one in which the channel slope has adjusted so that stream velocity is just enough to transport the sediment load.

A)graded
B)ungraded
C)equilibrium
D)disequilibrium
E)channel

Question 45

The total possible load a stream can transport is its ,whereas a stream's ability to move particles of specific size is its .

A)capacity;competence
B)competence;capacity
C)discharge;competence
D)bed load;sediment load
E)saltation;traction

Question 46

Bed load is moved by

A)saltation only.
B)traction only.
C)suspension only.
D)saltation,traction,and suspension.
E)both saltation and traction,but not suspension.

Question 47

The suspended load of a stream consists of particles that are

A)rolled along the stream bed.
B)held aloft in the stream flow.
C)dragged along the stream bed.
D)dissolved in solution.
E)bounced along the stream bed.

Question 48

The ultimate base level is

A)a drainage divide.
B)a dam.
C)sea level.
D)dependent on the geological substrate.
E)any hard,resistant rock in a channel.

Question 49

Stream transport involves all of the following except

A)saltation.
B)bed load.
C)traction.
D)sheetflow.
E)suspended load.

Question 50

A(n)is a stream which maintains an equilibrium between the processes of erosion and deposition and,therefore degradation and aggradation.

A)graded stream
B)oxbow
C)anabranching river
D)meandering stream
E)rill

Question 51

If the load exceeds a stream's capacity,sediment accumulates in the bed in a process called

A)downcutting.
B)degradation.
C)aggradation.
D)saltation.
E)traction

Question 52

The process whereby streams lengthen their channels upstream is called

A)headwater erosion.
B)channel incision.
C)stream piracy.
D)saltation.
E)traction.

Question 53

Which of the following may act as a local base level?

A)a lake that a river flows into
B)a drainage divide
C)the upper surface of a waterfall
D)an interfluve
E)the headwaters

Question 54

Which of the following is correct of the longitudinal profile of most rivers?

A)It always changes at a constant rate from the headwater region to the sea.
B)It is convex in shape.
C)It is concave in shape.
D)It is gentle upstream and steep downstream.
E)It is highest at the mouth and lowest at the headwaters.

Question 55

The sediment load that travels in solution is

A)bed load.
B)suspended load.
C)dissolved load.
D)flow load.
E)saltation.

Question 56

An interruption in a stream's graded profile of equilibrium is called a

A)gradation.
B)longitudinal interruption.
C)base level.
D)cutbank.
E)nickpoint.

Question 57

Stream piracy refers to

A)the legal process by which a state secures rights to the waters of a river basin.
B)the merging of two streams flowing in the same valley.
C)capturing the headwater regions of another stream by an eroding rill in another system.
D)the illegal withdrawal of water from a river.
E)upstream erosion leading the to the lengthening of the channel.

Question 58

Base level refers to

A)the amount of discharge in a particular reach of a stream.
B)a level below which a stream cannot erode its valley.
C)an evolutionary cycle of landscape development from fluvial action.
D)the average height of a stream channel.
E)the stream gradient.

Question 59

A graphic depiction of a streams gradient from its headwaters to mouth is called a(n)

A)altimeter.
B)Keeling curve.
C)hydrograph.
D)climograph.
E)longitudinal profile.

Question 60

The drop in stream elevation per unit distance is known as

A)discharge.
B)base level.
C)gradient.
D)aspect.
E)slope.

Question 61

Excess sediment may result in which of the following channel patterns?

A)V-shaped valleys
B)braided stream
C)meandering stream
D)straight,steep-walled channels
E)deeply entrenched U-shaped valleys

Question 62

Maximum velocity in a meandering stream is

A)near the bottom.
B)at the inner portion of the meander curve.
C)at the center and near the surface.
D)at the outer portion of the meander curve.
E)at the point bar.

Question 63

Which of the following is incorrect regarding floodplains?

A)They are formed by recurrent flooding in the area adjacent to the stream.
B)Natural levees on either side of a stream are formed during times when the stream is at flood stage and overflows the bank.
C)They are generally low-lying areas.
D)Residual deposits from abandoned channels often result in meander scars in floodplains.
E)They are characterized by rapids and low waterfalls.

Question 64

Which of the following is incorrectly matched?

A)cutbank - at outer portion of a stream meander
B)point bar - area of substantial erosion
C)aggradation - sediment accumulation in the stream channel
D)braided stream - maze of interconnected channels
E)undercut bank - area of erosion

Question 65

Maximum velocity in a straight channel is found

A)near the bottom.
B)near the inside of a meander.
C)at the center and near the surface,corresponding with the deepest parts of the stream channel.
D)at the center and near the surface,corresponding with the shallowest parts of the stream channel.
E)near either of the river banks.

Question 66

The portion of each meandering curve subject to the fastest water velocity undergoes the greatest erosive action.This action forms a steep

A)meander scar.
B)oxbow.
C)cutback.
D)point bar.
E)uppercut bank.

Question 67

The portion of each meandering curve subject to the slowest water velocity undergoes aggradation.This results in a(n)

A)meander scar.
B)oxbow.
C)cutback.
D)neck.
E)point bar.

Question 68

Channels with gradual slopes often develop a sinuous form called a(n)pattern.

A)braided stream
B)anabranching
C)meandering stream
D)straight
E)exotic

Question 69

As they migrate,meandering streams erode their out outside banks,often forming a narrow neck of land that eventually erodes through and forms a and the stream becomes .

A)meander scar;narrower
B)cutoff;straighter
C)cutback;more sinuous
D)point bar;wider
E)neck;longer

Question 70

Natural levees are created during

A)floods.
B)normal flow conditions.
C)low flow conditions.
D)degradation.
E)erosional events.

Question 71

Entrenchment of a channel occurs because

A)a decrease in stream gradient occurs.
B)a change in the bed load size-distribution occurs.
C)the river flows from consolidated rock into a region composed of loose sediments.
D)rejuvenation occurs due to uplift.
E)isostatic downwarping of the crust occurs.

Question 72

is the general term for unconsolidated clay,silt,sand,gravel,and mineral fragments deposited by running water.

A)Alluvium
B)Deposition
C)Aggradation
D)Degradation
E)Fluvium

Question 73

A maze of interconnected channels formed on a river with a high sediment load is known as a(n)stream.

A)braided
B)anabranching
C)meandering
D)straight
E)exotic

Question 74

A(n)is a meander that becomes isolated from the rest of the river.

A)oxbow lake
B)undercut bank
C)point bar
D)cutoff
E)cutbank

Question 75

A yazoo tributary stream cannot join with the main river in an area because

A)the yazoo flows in a different valley.
B)a small structural ridge separates the rivers.
C)a natural levee on the main river prevents joining.
D)a man-made flow control structure keeps the rivers separate.
E)a large topographic barrier,such as a mesa,separates them.

Question 76

As a stream's velocity decreases,which of the following sizes of sediments will be deposited last?

A)gravel
B)sand
C)silt
D)loam
E)clay

Question 77

A stream that downcuts at the same rate as tectonic uplift,thereby maintaining its course is called a(n)

A)meandering stream.
B)anabranching river.
C)antecedent stream.
D)rejuvenated river.
E)graded stream.

Question 78

The entrenchment of a river into its own floodplain can produce

A)backswamps.
B)alluvial terraces.
C)natural levees.
D)river deltas.
E)yazoo streams.

Question 79

The process whereby streams deepen their channel is known as

A)headwater erosion.
B)channel incision.
C)stream piracy.
D)saltation.
E)traction.

Question 80

Coarser particles generally settle out _,while finer particles settle out .

A)closer to the mouth;closer to the headwaters
B)along cutbanks;at point bars
C)at point bars;along cutbanks
D)closer to the mouth;not at all
E)closer to the headwaters;closer to the mouth