HideShow resource information
View mindmap
    • waterfalls and gorges are found in the upper course
      • 1)Waterfalls form where a river flows over an are of hard rock followed by an are of softer rock
      • 2)The softer rock is eroded more than the harder rock, creating a 'step' in the river
      • 3)As water goes over the step it erodes more and more of the softer rock
      • 4)A steep drop is eventually created, which is called a waterfall.
      • 5)The hard rock is eventually undercut by erosion.It becomes unsupported and collapses.
      • 6)The collapsed rocks are swirled around at the foot of the waterfall where they erode the softer rock by abrasion.This creates a plunge pool.
      • 7)Over time, more undercutting causes more collapses. The waterfall wil reteat (move back up the channel), leaving behind a steep-sided gorge
    • interlocking spurs form when rivers wind around hills
      • 1)In the upper course, most of the erosion is vertically downwards. This creates steep-sided, V-shaped valleys.
      • 2)The rivers aren't powerful enough to erode laterally (sideways)-they have to wind around the high hillsides that stick out into their paths on either side.
      • 3)The hillsides that interlock with eachother as the river winds around them are called interlocking spurs


No comments have yet been made

Similar Geography resources:

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