Ch. 11

The downstream portion of a river

generally is of higher velocity. although it is masked by reduced turbulence

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

it is concave in shape

Of the world's largest rivers, which has the greatest discharge

Amazon River

Rivers east of the continental divide in the Rockies drain into the

Gulf/Atlantic Drainage

An increase in turbulence

increases the river's erosive power

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

Width, depth, and velocity all increase.

Which of the following rock types is most affected by fluvial solution?

limestone

If you wanted to build a structure along a riverespecially one that flows through unconsolidated sediments you should build the structure ________ to maximize its lifetime.

Above the point bar

Which of the following is likely to occur if the gradient of a stream increases? (Assume that the discharge and sediment load remain unchanged.)

The stream will begin to erode its channel and/or its banks

Which of the following is incorrectly matched?

abrasion a hydraulic squeeze-and-release action

If the capacity of a stream is exceeded, ________ will occur

aggradation

The construction of a dam across a river is likely to cause ________ upstream and ________ downstream

aggradation; erosion

The degradation of a landscape by weathering, erosion, and transportation has an ultimate "goal" of reducing the landscape down to

base level, namely sea level

Rectangular drainage patterns form as a result of

flow through a faulted landscape

Stream-related processes are termed

fluvial

The lengths of the individual channels in a dendritic drainage pattern are ________ and this increases energy ________.

minimized; efficiency

Steep slopes and some relief generally produce which drainage pattern?

parallel

Stream capture refers to

the process by which one channel erodes through a drainage divide and captures the headwater regions of another stream

Which drainage pattern is controlled by rock structures of variable resistance and folded strata?

trellis

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

weathering, erosion, transport, deposition

Which of the following may act as a base level?

a lake that a river flows into and sea level only

Stream drainage patterns are determined by which of the following?

all of these

The general term for clay, silt, and sand deposited by running water is

alluvium

A cutoff on a meandering stream results in the formation of

an oxbow lake

The largest material that can be carried by a stream is carried as

bed load

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

clay

As base level is approached by a stream, the ability of a stream to erode its bed

decreases

A central peak, or a dome of a volcanic mountain, generally produces ________ drainage patterns

radial

Which of the following stream channel forms is likely to develop when aggradation greatly exceeds erosion?

braided channels

If a stream has just the gradient and discharge to transport its sediment load, it is said to be

graded

Stream transport involves all of the following except

sheet flow

In response to the occurrence of a local base level

sediments accumulate upstream in response to the loss of flow velocity

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

capacity; competence

Increased velocity and a rough channel can produce a

turbulent flow

A meandering stream is one that is

delicately balanced between equilibrium and chaos

John Wesley Powell put forward the idea of base level, which refers to

Both a and b are correct