Chapter 16

Question 1

A general term for sediment deposited by streams

Answer 1

Alluvium

Question 2

A stream down cuts its bed at a pace equal to the rate of uplift

Answer 2

Antecedent stream

Question 3

Small scale channel deposits where streams continually pick up sediment in one part of their channel and deposit it down stream

Answer 3

Bar

Question 4

The lowest elevation to which a stream can erode its channel; level at which the mouth of a stream enters the ocean, a lake, or a trunk stream

Answer 4

Base level

Question 5

Coarse material, including coarse sands, gravels, and even boulders typically move along the bed of a channel

Answer 5

Bed load

Question 6

Form at the end of glaciers, where there is a large seasonal variation in discharge

Answer 6

Braided stream

Question 7

The maximum load of solid particles a stream can transform per unit time

Answer 7

Capacity

Question 8

The measure of a streams ability to transport particles based on size rather than quantity

Answer 8

Competence

Question 9

the outside of a meander is a zone of active erosion; debris acquired by the stream at the ________ moves downstream where the coaster material is generally deposited as point bars

Answer 9

Cut bank

Question 10

Form where sediment-charged streams enter the relatively still waters of a lake, an inland sea, or the ocean

Answer 10

Delta

Question 11

Characterized by irregular branching of tributary streams that resemble the branching pattern of a deciduous tree

Answer 11

Dendritic pattern

Question 12

The quantity of water in a stream that passes a given point in a period of time

Answer 12

Discharge

Question 13

The portion of a streams load that is carried in solution

Answer 13

Dissolved load

Question 14

A section of stream that leaves the main flow

Answer 14

Distributary

Question 15

An imaginary line that separates the drainage of two streams, often found along a ridge

Answer 15

Divide

Question 16

The land area that contributes water to a stream

Answer 16

Drainage basin

Question 17

The overflow of a stream channel that occurs when discharge exceeds the channels capacity. The most common and destructive geologic hazard

Answer 17

Flood

Question 18

The flat, low lying portion of a stream valley subject to periodic inundation

Answer 18

Floodplain

Question 19

A stream that has the correct channel

Characteristics to maintain exactly the velocity required to transport the material supplied to it

Answer 19

Graded stream

Question 20

The slope of a stream, generally expressed as the vertical drop over a fixed distance

Answer 20

Gradient

Question 21

The extension upslope of the head of a valley due to erosion

Answer 21

Headward erosion

Question 22

The unending circulation of Earths water supply. The cycle is powered by energy from the sun and is characterized by continuous exchanged of water among the oceans, atmosphere, and the continents

Answer 22

Hydrologic cycle

Question 23

A meandering channel that flows in a steep, narrow valley. It forms when an area is uplifted or when the base level drops

Answer 23

Incised meander

Question 24

They movement of surface water into rock or soil through cracks and pore spaces

Answer 24

Infiltration

Question 25

The movement of water particles in straight line paths that are parallel to the channel. The water particles move downstream without mixing

Answer 25

Laminar flow

Question 26

The level of a lake, resistant rock layer, or any other base level that stands above sea level

Answer 26

Local base level

Question 27

A loophole bend in the course of a stream

Answer 27

Meander

Question 28

The point downstream where a river empties into another stream or water body

Answer 28

Mouth

Question 29

An elevated landform composed of alluvium that parallels some streams and acts to confine their waters, except during flood stage

Answer 29

Natural levee

Question 30

A curved lake that is created when a stream cuts off a meander

Answer 30

Oxbow lake

Question 31

A crescent shaped accumulation of sand and gravel deposited on the inside of a meander

Answer 31

Point bar

Question 32

A system of streams running in all directions, away from central elevated structure, such as a volcano

Answer 32

Radial pattern

Question 33

A drainage pattern characterized by numerous right angle bends that develop on jointed or fractured bedrock

Answer 33

Rectangular pattern

Question 34

Tiny channels that develop as unconfined flow begins producing threads of current

Answer 34

Rills

Question 35

Water that flows over land rather than infiltrating into the ground

Answer 35

Runoff

Question 36

Transportation of sediment through a series of leaps or bounces

Answer 36

Saltation

Question 37

Runoff moving in unconfined thin sheets

Answer 37

Sheet flow

Question 38

Diversion of the drainage of one stream that results from the headscarf erosion of another stream

Answer 38

Stream piracy

Question 39

A stream that cuts through a ridge lying across its path. The stream established its course on uniform layers at a higher level without regard to underlying structures and subsequently downcut

Answer 39

Superposed stream

Question 40

A flat, bench like structure produced by a stream, which was left elevated as the stream cut downward

Answer 40

Terrace

Question 41

A system of streams in which nearly parallel tributaries occupy valleys cut in folded strata

Answer 41

Trellis pattern

Question 42

Erratic movement of water often characterized by swirling, whirlpool like eddies. Most streamflow is of this type.

Answer 42

Turbulent flow

Question 43

Sea level; the lowest level to which stream erosion could lower the land

Answer 43

Ultimate base level

Question 44

A pass through a ridge or mountain in which a stream flows

Answer 44

Water gap

Question 45

Consists of coarse sediments that are deposited when mountain streams reach flat lowlands; where rapid streams emerge from a mountainous area onto a flatter surface, a distinctive cone-shaped accumulation of sediment forms

Answer 45

Alluvial fan