11.3 River erosion landforms

Question 1

What type of landforms are common at the river’s upper course?

Answer 1

➢ Interlocking spurs
➢ Waterfalls
➢ Gorges

Question 2

How are interlocking spurs formed?

Answer 2

➢ The river near the source of the river is not powerful enough to cut through the hard rock, so flows around them to form spurs

Question 3

How are waterfalls formed?

Answer 3

➢ When the river flows over a relatively resistant band of hard rock
➢ The river plunges of a waterfall it forms a deep and turbulent plunge pool
➢ The processes of erosion such as hydraulic action and abrasion combine to undercut the waterfall
➢ Eventually, the overhanging rock collapses and the waterfall retreats upstream

Question 4

What is a gorge?

Answer 4

➢ A narrow steep-sided valley that is usually found immediately downstream of a waterfall
➢ Formed by the gradual retreat of a waterfall