Erosional landforms

Question 1

What are the distinctive landforms found in upland areas of rivers?

Answer 1

Waterfalls, gorges, V-shaped valleys, interlocking spurs

These landforms are characteristic of the upper course of rivers due to erosional processes.

Question 2

What type of erosion is dominant in the upper course of a river?

Answer 2

Vertical erosion

This process deepens the river channel and shapes the landscape.

Question 3

What leads to the formation of a V-shaped valley?

Answer 3

Vertical erosion, weathering, and mass movement resulting in a steep sided valley

These processes cause material from the valley sides to collapse into the river.

Question 4

How do interlocking spurs form in the upper course of a river?

Answer 4

The channel starts to meander, causing erosion on the outside of bends

This results in the creation of interlocking spurs.

Question 5

What causes the formation of waterfalls?

Answer 5

A drop in the river bed due to changes in rock hardness

Hard rock overlies soft rock, leading to differential erosion.

Question 6

What erosional processes are involved in the formation of a waterfall?

Answer 6

Hydraulic action and abrasion

These processes erode the softer rock more quickly than the harder rock.

Question 7

What happens to the hard and soft rock during the formation of a waterfall?

Answer 7

The soft rock erodes quicker, undercutting the hard rock

This creates a plunge pool and an overhang of hard rock.

Question 8

What occurs to the overhang of hard rock over time at a waterfall?

Answer 8

It eventually collapses into the plunge pool

This increases abrasion and deepens the plunge pool.

Question 9

What is the result of the waterfall retreating upstream?

Answer 9

It leaves a steep-sided gorge

This is a continuous process of erosion and retreat.

Question 10

How must rock form for a waterfall to begin?

Answer 10

Hard rock lies on top of soft rock