11. Formation Of River Landscapes

• river basin - the area of land drained by a river system, including the river and its tributaries
• watershed - the boundary between two drainage basins (high ground), the area of land that drains into a river
• tributary - any stream or river which flows into another larger river
• confluence - where two rivers meet to form one larger river
• river course - the channel of a river, including the valley and floodplain
• floodplain - the flat plain on either side of the river channel, often covered with alluvium deposited during flooding
• levee - raised banks of sediment built up alongside the river channel as protection against flooding
• meander - bends in a river where erosion is most rapid due to high velocity of flow
• source - where the river begins, normally high ground
• oxbow lake - A lake formed by a meander of a river that has been cut off from its main channel
• river mouth - where the river meets the sea
• estuary - the part of a river that meets the sea and is tidal
• waterfall - vertical drop caused by erosion
• upper course/ youthful stage

  • vertical erosion is most powerful
  • fast flowing
  • thin river
  • waterfalls occur
• middle course/ mature stage

  • less steep
  • meanders occur
  • slows down
  • widens
• lower course/ old age stage

  • almost flat
  • deposition is common
  • levees occur
  • oxbow lakes occur
  • very slow
• v-shaped valley

  • narrow floor steep sides
  • abrasion and hydraulic action occur
  • eg Liffey in wicklow
• interlocking spurs

  • areas of high ground that jut out either side of the river
  • water meets hard rock so it flows around it
  • eg river barrow
• plunge pool - a pool of water that is under a waterfall
• Undercutting - when soft rock continues to erode under hard rock and leaves and overhang
• gorge - a narrow valley, with steep sides created by a retreating waterfall