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Flashcards in Chapter 16 Deck (60)
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1

hydrologic cycle

movement of water through Earth's four spheres

2

inflitration

precipitation soaks into the ground

3

runoff

precipitation runs over the surface

4

transpiration

water absorbed by plants and later transferred to the atmosphere

5

evapotranspiration

as evaporation and transpiration both move water from the surface to the atmosphere

6

Runoff starts as

sheet flow which develops into tiny channels called rills which forms gullies which form streams

7

streams

any water that flows in a channel, regardless of size

8

river

carries a substantial amount of water and has many tributaries

9

Drainage Basin

stream drains an area of land

10

Divide

the imaginary line separating one basin from another; sometimes visible as high ridge mountain region

11

3 zones of river systems

Sediment production, sediment transportation, sediment deposition

12

Sediment production

zone of a river where more sediment is derived
Located in the headwater region of a river system
Generated by: broken bedrock, bank erosion

13

Sediment transport

transported in trunk streams; amount of sediment being eroded equals amount being deposited

14

Sediment deposition

when a river reaches a large body of water, the energy decreases and river deposits sediments; usually only fine sediments are deposited in oceans

15

laminar flow

water flowing in a nearly straight path

16

turbulent flow

water moving quickly in an erratic fashion

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Factors affecting flow velocity

the slope, channel shape, roughness, discharge,

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The slope, or gradient of a stream

steeper gradient has more gravitational energy to drive channel flow

19

Channel shape

most effective channel has a small wetted perimeter (area where the rive is in contact with the channel) compared to its cross-sectional area

20

Channel size and roughness

increase in channel size will increase the cross-sectional area to wetted perimeter ration thus increasing efficiency; rough channels create turbulence and decreased velocity

21

Discharge

volume of water flowing past a certain point in a given unit of time
when discharge increases; the width, depth, flow, and velocity increase

22

longitudinal profile

cross-sectional view of a stream
most have a concave shape

23

head or headwater

source of the stream

24

mouth

the downstream point where the stream empties into a larger body of water
discharge, channel size, and velocity increases towards the mouth

25

Quarrying

involves removing large blocks from the channel bed

26

abrasion

scraping, bumping, and rubbing
erodes and polishes sediment s

27

Potholes

when fast moving, swirling sediment in eddies abrades a hole

28

Corrosion

rocks gradually dissolving in flowing water can occur in limestone bedrock channels

29

Transport of sediment by streams

Dissolved load (in solution)
Suspended load (in suspension)
Bed load (rolling along the bottom)

30

Dissolved load

most of the dissolved load is brought to a stream via groundwater
NOT affect by stream velocity