Rapids: Rapids are formed in areas of the river where the gradient is steep and the hard, resistant rock is worn down at a slower rate than the softer, less resistant rock surrounding it. A drop is created in the river, increasing the speed and turbulence of the flowing water (Fig. 8.15).
EXAM TIP
A relevant labelled diagram (optional) and a named example of the feature will be awarded 1 SRP each.
Fig. 8.15 Rapids. EXAM LINK (HL)
Surface Processes (30 marks)
Examine the impact of the processes of erosion on the formation of one fluvial landform that you have studied.
2015, Q1B Marking Scheme:
Named processes = 2 + 2 marks Named landform = 2 marks Examination = 12 SRPs × 2 marks
EXAM TIP
Answering this question using a waterfall is recommended, as they’re formed by a number of processes of erosion and have many associated features, each of which can be used to develop an SRP.
All processes mentioned should be explained and linked to the formation of the feature. CHECK YOUR LEARNING
1. List the three stages of river development. 2. What transportation processes are most active in the youthful stage of the river?
3. Explain the terms vertical erosion and bedload. 4. List and explain three processes in the formation of a V-shaped valley. 5. What evidence in the photo tells you the river is at the youthful stage in Fig. 8.11(b)?
6. List and explain the process that forms potholes. 7. Explain the process of ‘differential erosion’. 8. Explain the process of ‘headward erosion’. 9. How does an overhang form?
10. Name two Irish and two international waterfalls. 110
