Rivers

Question 1

What are the 4 types erosion?

Answer 1

Attrition, solution, abrasion, hydraulic action

Question 2

What are the four types of transportation?

Answer 2

Solution, suspension, Saltation, traction

Question 3

What is attrition?

Answer 3

Rocks that bash together to become smooth/Smaller

Question 4

What is solution?

Answer 4

A chemical reaction that dissolves rocks

Question 5

What is abrasion?

Answer 5

Rocks hurled at the base of the cliff to break pieces apart

Question 6

What is hydraulic action?

Answer 6

Water enters cracks in the cliff, air compresses, causing the crack to expand

Question 7

What is solution?

Answer 7

Minerals dissolve in water and carried along

Question 8

What is suspension?

Answer 8

Sediment is carried along in the flow of the water

Question 9

What is saltation?

Answer 9

Pebbles that bounce along the sea/river bed

Question 10

What is traction?

Answer 10

Boulders that roll along a river/seabed by the force of the flowing water

Question 11

What is the peak Discharge in a hydrograph?

Answer 11

The discharge in a period of time

Question 12

What is the lag time in a hydrograph?

Answer 12

The delay between peak rainfall and Peak discharge

Question 13

What is the rising limb in a hydrograph?

Answer 13

The increase in river discharge

Question 14

What is the falling Limb in a hydrograph?

Answer 14

The decrease in river discharge to normal level

Question 15

What are the physical causes of flooding ?

Answer 15

Long periods of rainfall
Impermeable rocks
Steep-sided valleys

Question 16

What are the human causes of flooding ?

Answer 16

Tarmac and concrete are impermeable

Question 17

What is deposition ?

Answer 17

When the sea or river loses energy, drops the sand, rock particles and pebbles it has been carrying

Question 18

Characteristics of middle course ?

Answer 18

Gentler gradient
Less energy water moves slower
Erosion laterally makes river wider

Question 19

What is precipitation ?

Answer 19

Moisture falling from clouds as rain, snow or hail

Question 20

What is interception ?

Answer 20

Vegetation prevent water reaching the ground

Question 21

What is surface runoff ?

Answer 21

Water flowing over surface of the land into rivers

Question 22

What is infiltration ?

Answer 22

Water absorbed into the soil from the ground

Question 23

What is transpiration ?

Answer 23

Water lost through leaves of plants

Question 24

What is the upper course of the river like?

Answer 24

The weather flows over the steep gradient from the hills/mountains, this gives the river a lot of energy, so it will erode the river bed vertically to form narrow valleys

Question 25

What is the formation of oxbow lakes?

Answer 25

Step 1: erosion of the outer bank forms Rivercliff and deposition of innerbank forms slip of slope Step 2: further hydraulic action and abrasion of outer banks, neck get smaller Step 3: erosion breaks through the neck so river takes the fastest route redirecting flow Step 4: evaporation and deposition cuts of main channel leaving an oxbow lake

Question 26

What are 3 soft engineering schemes to prevent flooding?

Answer 26

Afforestation Demountable flood barriers Manage flooding

Question 27

What are 3 hard engineering schemes to prevent flooding?

Answer 27

Straightening channel Artificial levees Deepening or widening river

Question 28

What 5 steps forms a waterfall?

Answer 28

Step 1: river flows over alternate types of rock Step 2: River erodes soft rock faster create a step Step 3: further hydraulic action and abrasion from a plunge pool beneath Step 4: Hardrock above is undercut leaving cap rock which collapses providing more material for erosion Step 5: waterfall retreats leaving steep sided gorge

Question 29

What is the lower course of a river like?

Answer 29

The river widens further and becomes flatter, material transported is deposited

Question 30

How are floodplains and levees formed?

Answer 30

When a river floods, fine salt is deposited on the valley floor closer to the river banks, the heavier material to build up to form natural levees

Question 31

What are two advantages of floodplains and levees?

Answer 31

Nutrient rich soil makes it ideal for farming Flat land for building houses