1. RIVERS AS AGENTS OF EROSION, TRANSPORTATION AND DEPOSITION
You should be able to:
Describe the changes in river characteristics as it flows downstream along its valley.
Describe the fluvial processes of erosion, transportation and deposition.

2. Add a line to show the profile of the typical river profile.

3. Complete your copy of the table Use the information on pages 56 
GRADIENT
Decreases downstream as vertical erosion decreases downstream
Progressively gentler gradients
DISCHARGE
Increases downstream as: more tributaries join, more water enters through baseflow and throughflow
VELOCITY
Depends on channel slope – steeper the slope the faster the river, rougher the sides the greater the friction and slower the river
VALLEY SHAPE
V-shape to more gentle gradient as vertical erosion decrease – steep sides. Interlocking spurs
EROSION (VERTICAL / LATERAL)
Vertical in the upper course as river cuts into the bedrock – moving towards base level
LOAD
Increases in quantity as river moves downstream due to erosion
Decreases in size and angularity downstream (attrition)
TRANSPORT
More energy is given to transportation in the middle course as the load of the river increases
TEXTBOOK PROFILE AFFECTED BY:
Waterfalls, local base levels
TASK:
Complete your copy of the table
Use the information on pages 56 
65 to help you.

4. EROSION TRANSPORTATION DEPOSITION
Corrasion / abrasion
Traction
Entering the sea
Hydraulic action
Saltation
Overflow the banks
Corrosion
Suspension
Inside bend of meander
Attrition
Solution
Reduction in discharge (drought)
Sudden decrease in gradient (base of waterfall)

5. RIVERS – PHYSICAL FEATURES
As in the lithosphere unit you are often asked to explain how physical
features are formed. Important tips:
Always use annotated diagrams in your answer, even when not specifically asked for them.
Practice drawing diagrams when you are revising.
Use simple line drawings – they are much quicker and easier to draw than artistic line diagrams.
Give plenty of detail on the processes – do not be fooled into thinking ‘this is easy – I have done this in Standard Grade’. There may be twice as many marks for a similar question at Higher
(c.12 marks for one feature).
When given a choice of features, choose the one you
can write most about.

6. RIVERS – PHYSICAL FEATURES
UPPER COURSE
MIDDLE COURSE
LOWER COURSE
Waterfalls
Meanders
Pot Holes
Ox-Bow Lakes
Interlocking Spurs
Levee
Braiding
River Terrace
Flood Plain
NOTE:
The BOLD and underlined features are most likely to be asked. You are often given a choice.

7. FEATURES OF THE UPPER COURSE:

8. Hard rock overlying soft rock Soft rock erodes more easily
WATERFALL
Hard rock overlying soft rock
Soft rock erodes more easily
(DIFFERENTIAL EROSION)
Eventually soft rock is worn away
This causes undercutting of hard rock
Nothing to support the harder rock which collapses
The process is repeated and the waterfall moves upstream. Headward erosion
Hydraulic action and abrasion lead to a deep plunge pool (fully explain these processes)
Erosion processes should be mentioned throughout answer
Differential erosion is important
Answers could be in the form of a series of annotated diagrams
Diagrams should show process:
Before
During
After
TASK:
Make a neat copy of figure
C (page 10 Connections)
Use the key to annotate
your diagram

9. The Upper Course
Tees
Etive
Tees
Etive
North Esk

10. WATERFALL
RETREATS . .
UPSTREAM . .
OVERHANG
PLUNGE
POOL
UNDERCUTTING
OF SOFT ROCK

11. Sinuosity – tendency for river to follow a winding path
MEANDERS
Development of pools (deeper flows / slower) and riffles (shallower flows / faster) lead to initial deviance from straight river course
Sinuosity – tendency for river to follow a winding path
Coriolis effect
Erosion on the outside of the bend due to faster and more powerful flow by hydraulic action
Deposition on the inside of bends due to slower, less powerful flow
Helicoidal (corkscrew) flow removes material
Migration of meanders downstream
Undercut banks / river cliffs and slip-off slopes / river beaches formed in this process
Cross section diagram and process diagrams
COPY FIGURE 3.35 ON PAGE 64
Coloured Pencils – The key is important!
SQA

12. Middle Course - Meanders

13. Large Meanders

14. Formation of an oxbow lake

15. NARROW MEANDER NECK
FUTURE
OX-BOW LAKE

16. River wears away outside bend of meander (lateral erosion)
OX-BOW LAKE
Small crescent shaped lake is formed from the over-development of meanders
River wears away outside bend of meander (lateral erosion)
Neck of meander narrows
River breaks through – usually during flood conditions
Meander is breached as river takes shorter/direct route
Deposition of sediment on river banks results in ox-bow lake being cut-off
LEVEE
Raised beaches
Formed by materials deposited during flooding
Level rises over time
Heaviest material deposited first resulting in a sloping affect as levee moves away from river
TASK:
Make a neat copy of figure 3.36
Including key