Rivers

Question 1

Describe the features of the rivers long profile in each section

Answer 1

Upper: steep, narrow and shallow. There is lots of vertical erosion and waterfalls and gorges form there

Middle: more wider,flatter and deeper because there is more lateral erosion you will find oxbow lakes and meanders

Lower: the widest, flattest and deepest part of the river as there is more deposition. You will find leevees and estuaries

Question 2

What are all the processes of erosion?

Answer 2

Abrasion: when the rocks crash into the river bed

Attrition: when rocks collide with eachother in the river

Solution: when rocks dissolve in the river

Hydraulic action: when water and air is forced into the cracks of the rock eroding it

Question 3

What are all the processes of transportation?

Answer 3

Traction: rolling of pebbles along the river bed

Saltation: the bouncing of pebbles on the river bed

Suspension: smaller finer material is picked up by the rivers current

Solution: particles are carried within the water

Question 4

How are waterfalls formed?

Answer 4

1. There are 2 bands of rock, hard rock and soft rock
2. Hydraulic action and abrasion erode the softer rock forming an undercut
3. The undercutting of the rock continues to erode until it forms an overhang
4. The overhang falls due to gravity into a plunge pool
5. The splash of the rock into the plunge pool erodes the back of the hard rock
6. Because of this the waterfall retreats up forming a gorge

Question 5

How are meanders and oxbow lakes formed?

Answer 5

1. Water is flung towards the outside fast flowing bend of the river eroding it and increasing the depth and energy if the river

2.lateral erosion undercuts the bank causing a steepdided river cliff to form

3. The inner bend is slow flowing and deposition occurs creating a meander

Question 6

How are leevees formed?

Answer 6

1. Water and sediment is held in the channel
2. When it rains the rivers discharge increases and Water and sediment pass over the top of the channel and the larger sediment is dropped of at the sides
3. More material is deposited over time and a natural barrier is formed

Question 7

Explain the case study of the river tees

Answer 7

• the river tees starts at the source on top of the pennines in the north east of England
• as it goes through each course features include high force waterfalls, meanders oxbow lakes and leevees are seen

Question 8

What are some hard engineering strategies?

Answer 8

Channelling straightening: cuts through meanders to create a straight channell, this allows for a faster flow and prevents flooding however they damage natural habitats

Embankments are raised river banks which hold more water but can get eroded over time

Dams and reservoirs regulate water and store it to prevent flooding however they ate very expensive

Question 9

What are some soft engineering strategies?

Answer 9

Flood preparation is when rivers are monitored to warn people if floods will occur however they are just based on predictions

Biodiversity is the planting of more trees so there is more infiltration to prevent flooding however it takes a long time to work