River valley Flashcards

1
Q

what is the rivers course

A

the path of a river as it flows downhill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 3 courses of a river

A

-upper
-middle
-lower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what do rivers form as they flow downhill

A

channels and valleys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does the long profile of a river tell you

A

how the gradient changes over different courses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what does the cross profile of a river show you

A

what a cross section of the river would look like

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

describe the upper course of a river

A

-steep
-v shaped valley
-steep sides
- narrow,shallow channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

describe the middle course of a river

A

-medium gradient
-gently, sloping valley sides
-wider deeper channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

describe the lower course of a river

A

-gentle gradient
-very wide
-very flat valley
-very wide deep channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

name the 2 types of erosion

A

lateral
vertical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what changes the cross profile of a river

A

vertical and lateral erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what’s vertical erosion

A

-deepens river valleys and makes the channels **v-shaped **
-dominant in upper course of river
-high turbulence causes rough rocks to be **scraped along river bed **causing intense downward erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what’s lateral erosion

A

-widens river valley and channel during formation of meanders
-dominant in middle and lower courses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are 4processes of a river

A

-hydraulic action
-abrasion
-attrition
-solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what’s hydraulic action

A

the force the water breaks rock particles away from the river channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what’s hydraulic action

A

the force the water breaks rock particles away from the river channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what’s abrasion

A

eroded rocks picked up by the river scrape and rub against the channel causing it to wear away

17
Q

what’s attrition

A

eroded rocks picked up by the river smash into each other and break into smaller fragments. their edges become rounded as they rub together

18
Q

what’s solution

A

river water dissolved some type of rock

19
Q

what are the 4 processes of transportation

A

traction
saltation
suspension
solution

20
Q

transportation is the

A

movement of eroded material

21
Q

what does the transport of material depend on

A

the velocity of the water and size of particles

22
Q

what is traction

A

large particles like boulders are pushed along the river bed by the force of water

23
Q

what’s suspension

A

small particles like silt and call are carried along the water

24
Q

what’s saltation

A

pebble sized materials are bounced along the river bed by the force of water

25
Q

what’s solution

A

soluble materials dissolve in the water and are carried along

26
Q

what’s deposition

A

when a river drops the eroded material it’s transporting

27
Q

where are waterfalls and gorges found

A

upper course of the river

28
Q

explain how a waterfall is formed

A

-river flows over area of hard rock and then soft rock
-the soft rock is eroded more then hard rock creating a step in the river
-as water goes over step it erodes more and more of softer rock
-steep drop

29
Q

where do waterfalls form

A

they form where a river flows over an area of hard rock followed by soft rock

30
Q

what are soft engineering methods to reduce the effect of flooding

A

-flood warning
-preparation
-flood plain
-zoning