Fluvial deposition is the process by which a river deposits the material it carries. A river deposits its load when it loses energy, such as when entering a lake or sea or during periods of drought. The largest materials are deposited first as the river loses velocity. If a river suddenly gains a large additional load from an event like a landslide, it will use all its energy to transport material, but will deposit any excess it cannot carry.

1. AS GEOGRAPHY
HYDROLOGY
4 QUESTIONS
REVISION
FLUVIAL
DEPOSITION

2. DEFINITION
Fluvial deposition is the laying down of material carried by a river (its
load).

3. QUESTION 1
What causes a river to deposit?

4. ANSWER
Rivers deposit load when they lose energy.

5. QUESTION 2
When does this happen?

6. ANSWER
When the river loses velocity (e.g. when it enters a lake or the sea)
and/or when it loses volume (e.g. during a period of drought).

7. QUESTION 3
Describe the sequence of deposition that usually occurs.

8. ANSWER
Rivers deposit the largest material first.

9. QUESTION 4
What happens if a river suddenly gains additional load?

10. ANSWER
The river will use all its available energy to transport the material. If the
amount of additional load is significant, e.g. following a landslide, and
there is more material than the river can carry, then deposition of the
excess will occur.

11. IMPORTANT
The river will use all its available energy to transport the material.
If the amount of additional load is significant, e.g. following a landslide,
and there is more material than the river can carry, then deposition of
the excess will occur.