Streams And Floods

Front 1

Stream

Back 1

A body of running water that is confined in a channel and moves downhill under the influence of gravity.

Front 2

Stream Channel

Back 2

A long narrow depression eroded by the stream into rock or sediment.

Front 3

Sheetwash

Back 3

A thin layer of unchanneled water flowing downhill

Front 4

Drainage Basin

Back 4

The total area drained by a stream and its tributaries (a small stream flowing into a larger one)

Front 5

Hydrologic Cycle

Back 5

The interrelationship of the hydrosphere:

Geosphere

Biosphere

Atmostsphere

The movement and interchange of water between the ocean, atmosphere, and land.

Front 6

Divide

Back 6

A ridge or strip of high ground dividing one drainage basin from another.

Front 7

Drainage Pattern

Back 7

The arrangement, in a map view, of a river and its tributaries.

Dendritic

Radical

Rectangular

Trellis

Hint 7

4 ct

Front 8

Dendritic Drainage Pattern

Back 8

Develop on uniformly edible rock or regolith and are the most common type of pattern. The pattern resembles branches of a tree or nerve dendrites.

Front 9

Radical Drainage Patterns

Back 9

The streams diverge outward like spokes of a wheel.

Front 10

Rectangular Drainage Pattern

Back 10

Tributaries have frequent 90 degrees bends and tends to join other streams at right angles.

Front 11

Trellis Drainage Pattern

Back 11

Parallel main streams with short tributaries meeting them at right angles.

Front 12

Stream Velocity

Back 12

The distance water travels in a stream per unit time.

High Velocity = Greater Velocity

Low Velocity = Lower energy

Front 13

Stream Gradient

Back 13

Downhill slope of the bed measured by ft; controls streams velocity.

Front 14

Discharge

Back 14

The volume of water that flows past a given point in a unit of time.

Discharge (cfs) = Avg stream width (ft)

x Avg depth (ft)

x Avg velocity (ft/sec)

Front 15

Stream Erosion

Back 15

Hydraulic Action

Solution

Abrasion

Hint 15

3 ways

Front 16

Hydraulic Action

Back 16

The ability of flowing water to pick up and move rock and sediment.

Front 17

Solution

Back 17

Can be a slow process. Rocks being dissolved by water through weathering and erosion.

Front 18

Abrasion

Back 18

The grinding away of the stream channel by the friction and impact of the sediment load.

Front 19

Potholes

Back 19

Depression that are eroded into the hard rock of a stream bed by the abrasive action of the sediment load.

Front 20

Stream Transportation of Sediment

Back 20

Bed Load

Suspended Load

Dissolved Load

Hint 20

3 ways

Front 21

Bed Load

Back 21

The large or heavy sediment particles that travel on the stream bed. They are moved by either traction or saltation.

Front 22

Traction

Back 22

Movement by rolling, sliding, or dragging

Ref. Bed Load

Front 23

Saltation

Back 23

A series of short leaps or bounces off the bottom.

Ref. Bed Loads

Front 24

Suspended Load

Back 24

Sediment that is light enough to remain lifted indefinitely above the bottom by water turbulence.

Front 25

Dissolved Load

Back 25

Soluble products of chemical weathering processes.

Front 26

Bar

Back 26

A ridge of sediment, usually sand and gravel, deposited in the middle or along the banks of a stream.

Front 27

Placer Deposit

Back 27

Are found in stream where the running water has mechanically concentrated heavy sediment.

Front 28

Braided Stream

Back 28

Flowing in a network of interconnected rivulets around numerous bars.

Characteristically has a wide, shallow channel

Front 29

Meanders

Back 29

Rivers that carry fine-grained silt and clay in suspension tend to be narrow, and deep, and to develop pronounced, sinuous curves.

Front 30

Point Bar

Back 30

The low velocity on the inside of a curve promotes sediment deposition sandbars that have been deposited on the inside of curves because of the lower velocity there.

Front 31

Meander Cutoff

Back 31

A new, shorter channel across the narrow neck of a meander.

Front 32

Oxbow Lake

Back 32

The old meander may be abandoned as sediment separates it from the new, shorter channel.

The cutoff meander becomes a crescent-shaped oxbow lake.

Front 33

Flood Plain

Back 33

A broad strip of land built up by sedimentation on either side of a stream channel.

Front 34

Natural Levces

Back 34

Low ridges of flood-deposited sediment that form either side of a stream channel and thin away from the channel.

Front 35

Delta

Back 35

A body of sediment deposited at the mouth of a river when the river's velocity decreases.

Front 36

Distributaries

Back 36

Small, shifting channels that carry water away from the main river channel and distribute it over the surface of the delta.

Front 37

Alluvial Fan

Back 37

A large, fan or cone shaped pile of sediment that usually forms where a stream's velocity decreases as it emerges from a narrow mountain canyon onto a flat plain.

Front 38

Downcutting

Back 38

The process of deepening a valley by erosion of the stream bed.

Front 39

Base Level

Back 39

It is a theoretical limit for erosion of the Earth's surface.

Ref. Downcutting

Front 40

Graded Stream

Back 40

A stream that exhibits a delicate balance between its transporting capacity and the sediment load available to it.

Front 41

Lateral Erosion

Back 41

The erosion and undercutting of a stream's banks and valley walls as the stream swings from side to side across its valley floor.

Front 42

Headward Erosion

Back 42

The slow uphill growth of a valley above its original source through bullying, mass wasting, and sheet erosion.

Front 43

Stream Terraces

Back 43

Steplike landforms found above a stream and its flood plain.

Formed may be benches cut in rock or they may be steps formed in sediment by deposition and subsequent erosion.

Front 44

Incised Meanders

Back 44

Meanders that retain their sinuous pattern as they cut vertically downward below the level at which they originally formed.