River Landforms

Meanders, ox-bow lakes, waterfalls/gorges, flood plains and levees.

HideShow resource information
View mindmap
  • River Landforms
    • Meanders
      • Formed by erosion and deposition.
      • In the middle and lower course, rivers develop large bends called meanders.
      • The current is faster on the outside bend because the channel is deeper.
        • Therefore more erosion takes place on the outside bend which forms river cliffs.
          • The current is slower on the inside bend because the channel is shallower.
            • Therefore eroded material is deposited on the inside bend which forms slip-off slopes.
      • Mississippi River and River Thames have meanders.
    • Ox-Bow Lakes
      • As meanders get larger over time, they can turn into an ox-bow lake.
      • Erosion causes the outside bends to get closer until there's only a small bit of land left in between the bends called the neck.
        • The river then breaks through this land, manly during a flood.
          • The river now flows straight through- not going round the bend because it is the shortest way.
            • Deposition eventually cuts off the meander, which forms an ox-bow lake.
    • Waterfalls and Gorges.
      • Formed by erosion.
      • Waterfalls form where a river flows over an area of hard rock followed by an area of soft rock.
        • The soft rock is eroded more than the hard rock, creating a step in the river.
          • As water flows over the step, it erodes more of the softer rock. A steep drop is eventually created which is called a waterfall.
            • The hard rock is undercut by erosion. Then it becomes unsupported and collapses.
              • The rocks that have collapsed are swirled round at the bottom of the waterfall, where they erode the soft rock by abrasion. This creates a deep plunge pool.
                • Overtime, more undercutting causes more collapses. This makes the waterfall retreat up the channel, which leaves a steep sided gorge.
      • Upper course.
      • High Force waterfall is a waterfall on the River Tees.
    • Flood Plain.
      • Formed by deposition.
      • Lower course.
      • The flood plain is the wide valley floor on both sides of the river that sometimes gets flooded.
        • When a river floods onto the flood plain, the water slows down and deposits the eroded material that it's carrying, This makes the flood plain higher.
          • Meanders move across the flood plain, making it wider.
            • The deposition that happens on the slip-off slopes of meanders also builds up the flood plain.
    • Levees
      • Formed by deposition.
      • Lower course.
      • Levees are natural embankments along the edge of the channel.
        • During a flood, eroded material is deposited over the whole flood plain.
          • The heaviest material is deposited closest to river channel, because it gets dropped first when the river slows down.
            • Over time the deposited material builds up creating levees along the edges of the channel.
      • The Yellow River in China has levees.


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Water and rivers resources »