rapids

• rapids are an example of erosion
• what are rapids

  fast-flowing, turbulent sections of a river where the river bed has a relatively steep gradient
• where are rapids found?

  in the upper course eg the river severn just south of ironbridge gorge, shropshire
• characteristics of rapids:

  • turbulent flow of water
  • white water
  • uneven river bed
  • steep gradient
• the ability of a river to erode its bed depends on the rivers energy, it also depends on the degree of hardness of the bedrock, in some cases, there may be vertical bedding, whereby alternate bands of hard and soft rock cross the channel. as water will erode the softer rock quicker, it will result in 'stepped' areas that create turbulent flow and therefore white water
• stage 1

  vertical bedding is alternate bands of hard and soft rock across the channel
• stage 3

  soft rock eroded more easily so river bed is lower
• stage 4

  turbulence and white water are created as river passes over the hard rock