Meanders and oxbow lakes

• What is a meander?


  A bend or curve in a river
• Where is the shallowest water in a meander bend?

  Inside bend
• Where is the deepest water on a meander bend??

  Outside bend
• Where does the most erosion occur in a meander?

  Outside bend
• What types of erosion occur on the outside bend?

  Hydraulic action and abrasion
• Why does most erosion occur on the outside bend?

  Because the faster current is on the outside bend leading to more erosion
• Why does a slip off slope/river beach form on the inside bend?

  Because of deposition due to the slow current not being able to erode
• Why does a river bank/overhang form on the outside bend?

  Because of the undercut from lateral erosion
• What causes the meander shape to change?

  Erosion on the outside bend and deposition on the inside bend
• What does erosion and deposition lead to in meanders?

  The neck of the land within the meander narrows
• What does narrowing of the meander neck cause?

  Causes the two outside bends of different meanders to touch
• What can cause the two outside bends to meet?

  During times of flood, the river cuts through the narrow neck
• What happens when two outside bends meet?

  A new river channel is created, and the rive flows down the shorter route, blocking off the old meander with deposition
• How is an oxbow lake formed?

  1. Neck narrows
  2. The two outside bends meet
  3. A new shorter channel is created which the river flows through
  4. The old meander is blocked off by deposition from the new river channel