REVISION AS CAMBRIDGE GEOGRAPHY: RIVERS - CROSS PROFILE OF A RIVER VALLEY.

1. AS GEOGRAPHY
HYDROLOGY
4 QUESTIONS
REVISION
CROSS PROFILE
OF A RIVER VALLEY

2. QUESTION 1
What shape would you expect the profile to be a) in the upper course,
b) in the middle course, c) in the lower course?

3. ANSWER
a) V-shaped
b) Open V-shaped
c) Wide and flat

4. QUESTION 2
Name three physical factors that influence the cross profile.

5. ANSWER
Geology, river energy/processes, mass movement, past processes
(glaciation), vegetation cover.

6. QUESTION 3
How does river erosion vary downstream?

7. ANSWER
In the upper course vertical erosion dominates, while in the middle
course lateral erosion is dominant. Little erosion occurs in the lower
course, except on the outside of meander bends.

8. QUESTION 4
What role does deposition play?

9. ANSWER
Deposition occurs mainly in the lower course and is responsible for
building the floodplain in a series of layers.

10. IMPORTANT
An important control on the cross profile is the relationship between
the rate of movement of material down the valley sides and the rate at
which this is eroded and removed. When describing a cross profile,
refer to the steepness of the valley sides and the width of the floor;
quote figures to convey a sense of scale.