Streams

Front 1

Hydrologic Cycle

Back 1

Percipitation, evaporation, infiltration.

Front 2

Rivers

Back 2

Formed by streams

Front 3

Streams

Back 3

Streams form by raindrop erosion transitioned to sheet erosions.

Front 4

Runoff

Back 4

Depends on soil infiltration capacity

Front 5

Determining factors of amounts of Runoff

Back 5

Intensity and duration of rainfall, prior wetted conditions of soil, soil texture, slope of land, nature of vegetation coverage.

Front 6

Drainage Basin

Back 6

Land area that contributes water to a river system

Front 7

Divide

Back 7

Separated Drainage Basins.

Front 8

Parts of Streams

Back 8

Zone erosion, Zone Transport, Zone deposition.

Front 9

How stream and rivers contribute to formation
of landscape.

Back 9

Erode channels in which they flow. Transport Sediments provided by weathering and slope processes. Produces a wide variety of erosional and depositional landforms.

Front 10

Controlling Factors of Stream Erosion

Back 10

(gradient, channel shape, size, roughness, discharge) Ability of a stream to erode and transport materials depends on its velocity. Friction, Meanders, centrifugal force. Gradient (slope of landscape), channel characteristics such as shape, size, and roughness of channel, and discharge.

Front 11

How Streams change in profile from head to mouth?

Back 11

Cross-sectional view of a stream from head to mouth. It is a smooth curve. Gradient decreases from the head to the mouth. Discharge = volume of water.

Front 12

Driving Factors of erosion in a stream

Back 12

Volume of water, higher velocity.

Front 13

Stream load

Back 13

Transported material by stream

Front 14

Types of stream loads

Back 14

Dissolved load (in solution), suspended load (in suspention) always has materials in water, Bed load (moved along bottom) particles drug, eroded or bounced on bed.

Front 15

Importance of watersettling velocities for the suspended load

Back 15

Type and amount of suspended load is contolled by water velocity and setting velocity of sediments. How heavy are materials and what is the velocity or energy it can carry.

Front 16

Competence

Back 16

Maximum particle size that can be transported.

Front 17

Capacity

Back 17

Maximum load that can be carried, directly related to discharge

Front 18

Causes of sediment deposition

Back 18

Caused by a decrease in velocity and competence

Front 19

Sorting

Back 19

The way sediments drop out in order of size

Front 20

Bedrock Channels

Back 20

Streams that are actively cutting into solid rock

Front 21

Alluvial Channels

Back 21

Bed and banks are composed mainly of unconsolidated sediments

Front 22

Meandering streams

Back 22

Streams that move in sweeping bends (meanders) and transport much of their load in suspension

Front 23

How meandering streams are formed

Back 23

Erosion occurs on side with high velocity deposition happens on side with lower velocity

Front 24

Braided streams

Back 24

Complex network of converging and diverging channels that transport much of their load as bed load.

Front 25

Where braided streams are found

Back 25

At the end mountain areas and and at the edge of glaciers.

Front 26

Base level

Back 26

Lower limit to how deep a stream can erode

Front 27

Temporary of local base level

Back 27

Lakes, resistant layers of rock, main streams.

Front 28

Stream Valley

Back 28

Consist of channel and surrounding terrain that contributes water to the stream.

Front 29

How stream valleys are formed

Back 29

Weathering, overland flow, and mass wasting.

Front 30

Charecteristics of narrow stream Valleys

Back 30

V-Shaped, down cutting toward base level, features often include (rapids and waterfalls).

Front 31

Characteristics of wide stream Valleys

Back 31

A stream that is near base level, downward erosion is less dominant. Stream energy is directed from side to side
creating the floodplain

Front 32

Ultimate Base level

Back 32

Sea level

Front 33

Sand Bar

Back 33

(temporary features) Made of sand and gravel are formed in the channels.

Front 34

Delta

Back 34

Exist in ocean or lakes

Front 35

Natural Levees

Back 35

On both banks in floodplain. Built by successive floods over time

Front 36

Floods

Back 36

Event of discharge of stream that exceeds capacity of its channel.

Front 37

Flashfloods

Back 37

Limited in extent and hard to predict. Rainfall intensity and duration, topography, surface conditions.

Front 38

Strategies put in place to try to control floods

Back 38

Artificial levee’s, flood control dams, and channelization.