Rivers

Question 1

What is the river bed and bank

Answer 1

River bed is the bottom of the channel but the river bank is the sides

Question 2

What is erosion

Answer 2

The wearing away of rock

Question 3

What is transportation

Answer 3

When material is moved downstream. The sediment gets smaller and rounder

Question 4

What is deposition

Answer 4

When the river loses energy and drops the material it was carrying

Question 5

What is Hydraulic action

Answer 5

Where the river banks have cracks where water and air are compressed so the cracks widen and break off

Question 6

What is abrasion

Answer 6

When the rocks scrape the river bank and bed, eroding it, making the rocks smoother

Question 7

What is attrition

Answer 7

When the rocks collide and break away

Question 8

What is a solution

Answer 8

When the water is slightly acidic due to absorption of carbon dioxide and the rocks dissolve

Question 9

What is a source

Answer 9

Where a river begins

Question 10

What is a tributary

Answer 10

A small stream that joins a larger one

Question 11

What is it called when 2 rivers meet

Answer 11

Confluence

Question 12

What is the mouth

Answer 12

Where the river joins the sea

Question 13

What is the watershed

Answer 13

The border surrounding a river basin

Question 14

What is vertical erosion

Answer 14

It erodes downwards and can create V shapes

Question 15

What is lateral erosion

Answer 15

Where the outside bend gets eroded

Question 16

What is the valley shape

Answer 16

Describes the shape of a river where it could be steep or flat, wide or narrow

Question 17

What is traction

Answer 17

Where the river banks roll along the river bed

Question 18

What is saltation

Answer 18

The small rocks bounce across the river

Question 19

What is suspension

Answer 19

Where light material is carried without touching the river bank and bed

Question 20

What is gradient

Answer 20

The angle of a river

Question 21

What is discharge

Answer 21

The volume of water moving downstream

Question 22

What is velocity

Answer 22

The speed

Question 23

Describe the upper course

Answer 23

It will be shallow and narrow moving at a slow speed with big angular rocks with a steep shape

Question 24

Describe the middle course

Answer 24

It is deeper and moving at a moderate speed where it is carrying medium sized, sub angular rocks along a shallow gradient

Question 25

Describe the lower course

Answer 25

It is deep carrying small, smooth rocks in fast water on a flat gradient

Question 26

Describe the stages of a waterfall forming

Answer 26

1. River flows over hard rocks and soft rock
2. The soft rocks erodes quicker forming a step in the river bed
3. The water undercuts the hard rocks making a plunge pool
4. There is an overhang and it repeatedly cracks because it is not supported
5. The rocks swirl in the plunge pool causing erosion
6. The waterfall repeats this process and recedes

Question 27

What are meanders

Answer 27

Bends in a river

Question 28

How are meanders formed

Answer 28

1. It starts as a slight bend and the discharge is high on the outside bend
2. The erosion is on the outside bend but deposition is happening in the inside bend
3. It turns in a meander
4. It forms a light loop over years
5. The water level is really high and can go straight through the loop not around
6. This is called a meander cutoff
7. The river uses the new channel so the deposition builds up and the loop is left as an oxbow lake
8. The lake dries up and grows plants

Question 29

Give an example of flooding defences

Answer 29

York embankments which is a permanent raised bank of earth which can have items built on it