Ox-bow lakes are horseshoe-shaped lakes found on the flood plains of old rivers. They are formed by river erosion and deposition. An example can be seen on the River Moy.
During floods, river takes shortest course through the neck
Cut-off/Abandoned meander or ox-bow lake
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Erosion makes the neck narrow
New, straighter river course
Areas of deposition Formation
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Erosion by hydraulic action and abrasion takes place on the outside bank of the meander. The neck of land between the meander begins to narrow.
During times of flood, the water has increased energy. It takes the shortest course by breaking through the neck and begins to flow in a new, more direct course.
Deposits of alluvium now build up and seal off both ends of the meander. The old section of the meander is now cut off from the main river and becomes known as an ox-bow lake. Over time, the lake may dry up.
Areas of erosion
Communicating:
Look at the photo and pinpoint the ox-bow lake. Using a pencil, trace from the river to the ox-bow lake and try to discover what the old course of the meander may have looked like. After you have done this, turn to the person next to you and compare your work.
