Goegraphy Revision Notes

HideShow resource information
  • Created by: Lauren
  • Created on: 03-03-13 15:11

Types of Weathering

Weathering is the break down of rocks in the same place (situ)

Erosion- the break down of rocks and the subsequent removal of the material

Freezethaw- is a physical weathering where when water fills up in the cracks during the night the water freezes and expands.

Biological- To do with animals and plants that cause the rocks to weather

Chemical- is the down pour of acid rain that erodes the rocks. It is a chemical rewaction

Exfoliation- is a physical weathering and when the rock surface weakens and then it expands, the night colls rapidly down and the rocks stay like that.

1 of 17

Methods of Transportation

(http://www.bbc.co.uk/schools/gcsebitesize/geography/images/riv_004.gif)

  • Solution - minerals are dissolved in the water and carried along in solution.
  • Suspension - fine light material is carried along in the water.
  • Saltation - small pebbles and stones are bounced along the river bed.
  • Traction - large boulders and rocks are rolled along the river bed
2 of 17

Erosion

Atrition- Where material is moved along the bed of a river , cthen collides with other material and breaks up into smaller and smaller pieces.

Corrasion- Fine material that rubs against the river bank. The bank is worn away, by a sort of sand papering action called abrasion.

Corrosion- Some rocks forming the banks and bed of a river are dissolved by acides in the water.

Hydraulic Action- The sheer force of the water hitting the banks of the river.

3 of 17

River Tees- Source to Mouth

Source is in the Midlands in Cumbria. They get a relief rainfall in Cumbria because its very high.

Then a v-shape valley going down the moutain. The rocks bedded in the stream are angler.

Resivours in the Upper Course. A build up of water. It is captured using the steep v-shape valleys.

20 cubic metres a secound- high force waterfall which is in the Upper Course.

At the begging of the middle Course, the land is flatter and crops can be grown on the land. The river brings lots of minerals and fertile soil.

The rocks are smoother and the lake is wider

Meanders can occur at any place in the river. Frequently in the middle course

Yarm was built right in the middle of a meanders. River channel is very deep and wide.

4 of 17

A Drainage Basin

A Drainage Basin- an area of land drained by a river and its tribuatry.

Watershed- The boundary of a drainage basin

Mouth- The end of a river where it enters the sea or lake

Channel-Where a river flows. It has a bed and 2 banks

Confluence- The point where 2 rivers meet

5 of 17

Features of a River

Upper Course

Steepsided valley

narrow river channel

large bedload from valleysides

Middle Course

Meanders and Oxbow lakes

Lower Course

Floodplains

Leeves

6 of 17

How we use rivers

1. For our water supply

2. For making electricity - building dams on fast flowing rivers and power stations pump water out of the river and boil to make steam

3. For Farming

4. For industry - many factories use water to wash things or to cool tanks where chemicals are reacting

5. For transport - boats

6. For leaisure and pleasure - fishing, swimming

7. As a dump- for drains and where the water gets cleaned up and put back into the river

...and how we abuse them- by putting posinous stuff down the drains and waste liquid from homes and farms contain nitrates and phosphates.

7 of 17

7 main causes of flooding

Climate- Heavy Rainfall

Human- Dam failure, Deforestation, Urbanisation

Physical- rapid snow melt, saturated ground. tidal surge

8 of 17

River Tees

The River Tees can be found in northern England. The source of the river is located at Cross Fell in the North Pennines, the river flows east for 85 miles until it reaches its mouth and flows into the North Sea between Hartlepool and Redcar near Middlesbrough.

As the river travels from source to mouth, it passes through different villages and towns with many thriving local businesses

The river continues to be enjoyed from people from all walks of life, with the improvement in water quality and surrounding environment being credited to hard work of many groups and local residents. As the river flows through Teesside the local population have reconnected with their local river as the overall improvements over the last decade have left them with a pleasant place to spend time with the full family.

9 of 17

Effects of Cumbria Floods

Some of the effects from the Cumbria Flooding

- 1,200 people were left without electricity.

-  Many roads and bridges were closed

- Fire crews worked hard to pump water out of people's homes

- Cockermouth, at the confluence of the river Cocker and Derwent, suffered the worst flooding. Water was up to 2.5m in places

10 of 17

Responses to Flooding

Hard Management Schemes:

Using technology to try and stop flooding

Soft Manegment Schemes:

Works in the cunstrants of the natural environment

11 of 17

Strategys:

Flood Walls:

Advantages:

are effective when in use

Disadvantage:

Built around settlements and important location, also they are very expensive and don't look natural.

Flood Warnings:

Advantages:

It is the local radio and tv stations and have a much better prediciton and also they are not expensive.

12 of 17

Hard Management River Strategy Case Study

Name: The three Gorges dam

Location: China at Yichang on the River Yangtse

Size: 181m high and 2.3km wide

Cost: $25.5 billion

Area Flooded: 632km squared

Economic Benefit- flood control and a navagation and power generation.

Social Benefit- Decreases flooding and protects over 25,000 ha of farmland

Environmental Benefit- Increases depth by 110m and the disadvantage is that it gets heavily polluted from shipping and waste discharged from cities.

13 of 17

Some Defintions

Dredging- deeping the river channel by removing sand and silt

Estuary- the drowned river mouth in a lowland area

Flood Plain- the flat area of land on either side of a river in its lower course

Gabions- rocks set in wire cages to reduce erosion

Impermeable- does not allow water to pass through

Infiltration- the rate at which water may pass through soils or rocks

Reservoir- An artificial lake built to store water

River basin- the area of land drained by a river

Sustainable Development- new developments that do not destroy the environment but may improve it.

14 of 17

Kielder Water

Built in the 1900 to provdie water for the wollen trade

The scheme was approved by parliement in 1974

Work started in 1975

Took 2 years to fill in the valley

It cost £167M

Refurbised in 2005-2006

LArgest Reservoir in the Uk by capacity- 200 billion litres

27.5 mile Shoreine

10km long

Area 10 squared

15 of 17

Preventing Floods

1.Control the water levels- by building a dam and pumping stations

2. Build flood defences- build up the river banks to make embankments to keep water in, or build flood barriers around built-up areas to keep water out

3. MAke the river channel bigger- by dredging the river out

4. Improve street drainage- make sure that the street can cope with ehavy rainfall and that they are cleaned

5. Control land use around the river- stops people building on flood plains and to plant more trees in the drainage basin.

16 of 17

EFFECTS ON CUMBRIA FLOODING

Some of the effects from the Cumbria Flooding

- 1,200 people were left without electricity.

-  Many roads and bridges were closed

- Fire crews worked hard to pump water out of people's homes

- Cockermouth, at the confluence of the river Cocker and Derwent, suffered the worst flooding. Water was up to 2.5m in places

17 of 17

Comments

Connah Greenhalgh - Team GR

you could be more specific about the title -include rivers , prevention of floods , management etc 

Similar Geography resources:

See all Geography resources »See all resources »