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Landscapes of the UK - Coggle Diagram

- - - - Vertical erosion happens due to hydraulic action and abrasion. This leaves very steep valley sides that are then attacked by weathering processes such as freeze thaw and biological weathering. This weakens the valley sides which may collapse or cause some material to move down slope due to mass movement processes such as sliding.
  - - - In a straight channel the water flows from side to side, this can erode the river banks.
      - undercutting on the river bank causes the overhang to collapse, which forms a steep river cliff due to erosion.
      - on the inside bend of the meander, deposition occurs where the water is slower
      - when the river slows down and loses energy, it deposits its load to form a slip off slope
  - - - Erosion (hydraulic action and abrasion) take place on the outside of a river bend
      - The neck of the meander becomes narrower as the erosion continues. This is sometimes called a 'swans neck' meander.
      - At times of high discharge, flooding, the river breaks through the neck of the meander and becomes straight.
      - the old meander is now separated from the main river channel and deposition of sediment will eventually fill it in.
  - - - As water overtops the river banks, the water slows down from being very fast and loses energy
      - This causes sediment to be dropped on the river bank
      - Larger sediment is dropped first, which catches/traps the smaller sediment.
      - When the river flood again, the levees get larger and larger as more sediment is dropped
  - - - It is formed over many thousands of years after a river floods and deposits fine material in layers either side of it. After successive floods the height of the floodplain increases as further sediment is desposited.
- - - - Hydraulic action - water is forced into cracks, which creates weaknesses in rocks, splitting them apart
      - Abrasion - sediment is thrown against a surface by water and causes the sediment to rub and wear away material (smooth)
      - Attrition - pebbles hit each other making the rocks break and get smaller and rounder.
      - Solution - rocks are dissolved in water by a chemical reaction.
  - - - Mechanical weathering - the physical actions of rain frost and wind that create weaknesses in rocks.
      - Biological weathering - actions of living organisms such as plants and burrowing animals breaking down rocks.
      - Chemical weathering - minerals in the rocks reacting with chemicals, such as acid rain.
  - - - Traction: Large boulders are rolled along the river bed or sea bed
      - Saltation - smaller particles are bounced along the river bed.
      - Suspension - very fine particles float
      - Solution - rocks dissolve and are carried by the river.
  - - - Sliding: Rock or lose material slide downhill, often due to heavy rain
      - Slumping: Collapse of weak rock, such as sand and clay. Again this is due to heavy rainfall.
- - - - Fancy term that means rock type.
      - Igneous Rocks - Very hard (Granite and Basalt). Very old rocks, they are impermeable so often will have rivers on their landscapes. As they are hard they erode and weather very slowly so lead to make up upland areas.
      - Sedimentary Rocks - much softer than igneous. (Chalk and limestone) They are permeable so will let water through them which means that there landscape is less likely to have rivers, they are soft so erode and weather more quickly that igneous rocks so lead to lowland areas.