REVISION AS CAMBRIDGE GEOGRAPHY: RIVERS - MEANDER.

1. AS GEOGRAPHY
HYDROLOGY
4 QUESTIONS
REVISION
MEANDER

2. DEFINITION
Meander is a sinuous wave-like form in a river channel.

3. QUESTION 1
In which part of a meander is river velocity a) fastest, b) slowest?

4. ANSWER
a) On the outside of the meander bend
b) On the inside

5. QUESTION 2
How is sinuosity measured?

6. ANSWER
Length of channel divided by straight-line distance; if sinuosity is greater
than 1.5, then the channel is classed as meandering.

7. QUESTION 3
What is the typical relationship between meander wavelength and
channel width?

8. ANSWER
Wavelenght = 7-10 x channel width.

9. QUESTION 4
When do meanders usually develop?

10. ANSWER
When bed/bank material is silt/clay and when channel gradient is
moderately steep, so that the banks can be eroded.

11. IMPORTANT
Meanders are a complex phenomenon and at AS level it is enough to be
aware of some of the theories that explain their formation.
Theories include pool/riffle spacing, helicoidal flow and
discharge/sediment relationships.
Once formed, meanders may develop, migrate and eventually form
oxbow lakes when the neck is breached to form a cut-off that is sealed
off by deposition.