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Unit A1 - Physical World

This unit comprises of three sections; rivers, coasts and glaciation.

Rivers

Rivers begin in upland areas (the source) and flow downhill to the sea (the mouth). The river runs through a drainage basin. A river has three recognisable stages; upper, middle and lower. The river and its valley undergoes changes as it flows through these stages. These changes are:

The three stages of the river have different landforms occurring. Features of the upper course include v-shaped valleys, interlocking spurs and waterfalls.

  1. V shaped Valley
  2. Interlocking Spurs
  3. Waterfalls (e.g. Niagara Falls)

In the middle course of the river, the features are meanders.

  1. Meander

In the lower course of the river, the features include ox bow lakes, floodplain's, levees and deltas.

  1. Ox Bow Lake
  2. Floodplain
  3. Levee
  4. Delta

Typical questions on rivers will NOT focus on case study material. They will require detailed knowledge of the formation of each landform and will sometimes ask for diagrams to aid your answers. They may also ask about changes between stages of the river and reasons for these.

You will be taking part in fieldwork to the River Glaven to look for the changes in the river across the stages.

Glaciation

A glacier is formed when snow collecting on the ground is compacted creating ice because the air is removed. After repeated snowfalls, the ice will become thicker and under the influence of gravity may move downhill.

Glaciers are so large that they have the capacity to erode and do so in one of two ways:

  1. Plucking
  2. Abrasion

Examiners will ask about the formation of landforms in glacial valleys. You will not only need to describe and explain the formations but also be able to draw diagrams (see p.17 - 19 of TG for diagrams). The following are simplified stages of formation for the most common landforms:

  1. Corries
  2. Aretes
  3. Pyramidal Peak
  4. U shaped valleys and truncated spurs
  5. Hanging Valleys
  6. Ribbon Lakes (e.g. Wastwater, Lake District)
  7. Moraine (deposition landform)

Coasts

To understand the landforms that occur along coasts, it is important to understand erosion and weathering. There are four types of erosion that you must be able to explain in terms of how they contribute to the landforms:

  1. Hydraulic Action
  2. Corrasion
  3. Corrosion
  4. Attrition

Erosion is the main way that the sea attacks the cliff, but the cliff also undergoes attack from weathering and mass movement:

  1. Physical Weathering
  2. Chemical Weathering
  3. Biological Weathering
  4. Mass Movement

Two types of waves exist which have different characteristics:

  1. Constructive Waves
  2. Destructive Waves

Not only does the sea erode but it also transports material using a method called longshore drift (LSD). Waves hit the beach at an angle (of the prevailing wind) and sand and pebbles are carried up the beach (swash). Waves returns to the sea in a straight line (backwash). In this way material is transported along the coast until an obstacle is met.

Erosion creates a number of landforms along a coast that you will need to be able to explain and draw diagrams of if asked:

  1. Headlands and Bays (e.g. Swanage)
  2. Cliffs and Wave Cut Platforms
  3. Caves, arches, stacks and stumps (e.g. Durdle Door, Dorset)

Deposition on the coastline by constructive waves also creates landforms:

  1. Beaches
  2. Spits
  3. Bar

The examiners will NOT ask for case study material but it may be a good idea to know some named examples of the landforms found on the coast. Your GCSE coursework is also based on coasts so you will need to general information on wave types, erosion and weathering.

Homework Help:

  1. Factsheet on a river in England - choose any river in this country and write at least 5 facts on it. Facts can include location source, mouth, length, landforms present along its course, picture, etc.
    River Thames
  2. Cross Section of a river.
  3. River Glaven - complete write up from fieldwork. You must ensure you answer the hypothesis set before the trip and fully support it with your findings.
    River Glaven Conservation Group
  4. Identifying rivers in different stages - decide which O/S map is characteristic of each stage of a river. Make sure you give at least 2 reasons why for each.
  5. Find examples of a wave cut platform, wave cut notch and a spit.
  6. Athabasca Write up - following mystery in lesson write an extended answer to the question 'Why did Mr Johnston visit the Athabasca glacier in British Colombia, Canada every year for over 40 years?'
  7. Coasts booklet - answer questions 1,2,3,5,6,13,14 and 15. Use Tomorrows Geography and exercise book to help.