Rivers

• Upper Course

  • Small river

  • Flows down steep slopes

  • Erodes river bed vertically

  (downwards)

  Features

  • V-shaped valley

  • Interlocking spurs

  Waterfalls
• Middle Course

  • Large river

  • Flows quickly down

  gentle slopes

  • Erodes river banks

  laterally (sidewards)

  Features

  • Meanders

  • Wide valleys
• Lower Course

  Very large river

  • Flows on flat slopes

  • Deposits lots of material

  carried from upstream

  Features

  • Ox-bow lakes

  • Flood plains

  • Deltas

  • Levees
• v shaped valley - When a river is in its youthful stage, it erodes vertically (downwards). This forms

  a valley with steep sides and a narrow floor. The valley is called V-shaped as it

  looks like the letter V. V-shaped valleys are a feature of erosion in a river.

  An example can be seen in the youthful stage of the River Liffey.
• Interlocking spurs are areas of high ground

  that jut out on either side of the river and

  appear to lock together.

  Examples can be seen

  in the upper course of

  Working with others:

  the River

  Slaney.
• A waterfall occurs where a river flows over a vertical

  slope. Waterfalls are a feature of erosion.

  An example of a waterfall can be seen at Powerscourt,

  Co. Wicklow.

  Formation
• Wide Valley

  In the mature stage of a river, erosion

  occurs laterally (sideways) rather than

  vertically (downwards). This creates a

  wide river valley that is not very steep.

  Interlocking spurs have been removed by

  lateral erosion, which widens the valley

  floor. Weathering and mass movement have

  also made the valley sides less steep.
• Flood plains

  A flood plain is an area of flat land on either

  been built at this location?

  side of the river channel found in the mature

  2. Why might you not wish to build a factory too close

  to this river? Give two reasons for your answer.

  and old stages of a river. Flood plains are covered

  in fertile soil, known as alluvium. This rich and

  fertile soil is full of minerals and so is excellent for farming.
• Meanders

  Meanders are formed by a

  combination of erosion and

  deposition in the mature and

  old age stages of a river.

  An example of a meander can

  be seen in the middle and lower

  course of the Rivers Shannon

  and Boyne.
• Leeves

  A levee is a build-up of alluvium on the

  banks of a river and is a feature of the old

  stage river. Levees are caused by floods and

  are a feature of deposition.

  They can be seen in the lower course of the

  River Liffey and the River Moy, Co. Mayo.
• Ox-Bow Lakes

  Ox-bow lakes are horseshoe-shaped lakes found on the flood plains of

  old rivers. They are formed by river erosion and deposition. An example

  can be seen on the River Moy.
• Formation of meanders - Water flows more quickly on the

  outside of the river bend. The river

  erodes the bend by a combination of

  hydraulic action and abrasion.

  2 Water flows more slowly on the

  inside bend of the river. Material is

  deposited on the inside bend as the

  river loses energy nere
• Features of River deposition

  deltas

  leeves
• River you studied - River Liffey co.Dublin lreland