Formation of landforms - Erosion

Question 1

Where are waterfalls and gorges found

Answer 1

upper course of a river

Question 2

How do waterfalls form

Answer 2

where a river flows over an area of hard rock followed by softer rock, softer rock is eroded (by hydraulic action and abrasion) more than the hard rock = step, water goes over the step and erodes more of the softer rock, a steep drop is eventually created

Question 3

How do gorges form

Answer 3

after a waterfall is formed, the hard rock eventually undercut by erosion and collapses due to no support, 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, over time more undercutting causes more collapses making the waterfall retreat

Question 4

How do interlocking spurs form

Answer 4

rin the upper course of a river most of the erosion is vertical so when there are hard rocks the river aren’t powerful enough to erode sideways so they wind around the high hillsides, hillsides that interlock with each other as the river winds around are called interlocking spurs