26: Formation of an oxbow lake

1) Look carefully at the photo above. Draw arrows to label the following:

- S-shaped meander

- meander neck

- inside bend of a meander

- outside bend of a meander

- site where erosion might be occurring

- site where deposition might be occurring.

2) Look at the diagrams and the writing on the next page. They explain how an oxbow lake is formed, but they are muddled up.

Decide which piece of writing goes with which diagram. Cut out the diagrams and the writing. Paste them in the correct order, on paper.

The water flows round the meander. Erosion occurs on the outside bend and deposition occurs on the inside bend.	Over time, deposits of mud and earth build up by the backwater. The backwater is eventually cut off, leaving a kidney-shaped oxbow lake behind.
The water breaks across the neck of the meander. For a short time, water flows round the backwater and across the neck of the meander.	The water is flowing the fastest on the outside bend. Over time, the meander becomes an S shape. A thin strip of land called a neck is created at the beginning and the end of the meander.

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3) On the diagrams, label the following features:

- oxbow lake
- backwater
- neck of a meander

4) What do you think will happen to the oxbow lake over time? Why?

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