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Flashcards in River processes and pressures Deck (92)
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1

What is the gradient like in the upper course?

Steep

2

What is the discharge like in the upper course?

Small

3

What is the depth like in the upper course?

Shallow

4

What is the channel shape like in the upper course?

Narrow, steep sides

5

What is the velocity like in the upper course?

Quite fast

6

What is the valley shape like in the upper course?

Steep sides

7

What features are found in the upper course?

Waterfalls, interlocking spurs

8

What is the gradient like in the lower course?

shallow gradient

9

What is the discharge like in the lower course?

Very large

10

What is the depth like in the lower course?

Deep

11

What is the channel shape like in the lower course?

Flat floor, gentle slopping sides

12

What is the velocity like in the lower course?

Very fast

13

What is the valley shape like in the lower course?

Flat, gentle slopping sides

14

What features are found in the lower course?

Meanders, floodplains, levees and ox-bow lakes

15

What is the gradient like in the middle course?

Less steep

16

What is the discharge like in the middle course?

Large

17

What is the depth like in the middle course?

Deeper than the upper course

18

What is the channel shape like in the middle course?

Flat, steep sides

19

What is the velocity like in the middle course?

Fast

20

What is the valley shape like in the middle course?

Flat, steep sides

21

What features are found in the middle course?

Meanders and floodplains

22

What are the four main processes of erosion?

Hydraulic action
Abrasion
Attrition
Solution

23

What is hydraulic action?

The force of water on the bed and banks of the river removes material

24

What is attrition?

The load that is carried by the river bumps together and wears down into smaller, smoother pieces

25

What is abrasion?

Material carried by the river rubs against the bed and banks and wears them away

26

What is solution?

Some rock minerals dissolve in the river (limestone and chalk) and are carried along in the flow

27

What are the four main types of transportation?

Traction
Saltation
Suspension
Solution

28

What is traction?

Large boulders roll along the river bed

29

What is saltation?

Smaller pebbles are bounced along the river bed, picked up the dropped as the flow of the river changes

30

What is suspension?

Finer sand and silt particles are carried along in the flow, giving the river a brown appearance