Why does deposition occur on the inner bend
As the river makes its way to the middle course , it gains more water and therefore more energy, so material can be carried in suspension and is used to erode the river banks. Lateral erosion starts to widen the river.
When a river flows over flatter land it develops large bends called meanders. Due to erosion on the outside of a bend and deposition on the inside, the shape of a meander will change over a period of time. Thus by eroding its outer bank and depositing material along its inner bank, a stream moves sideways without changing its channel size.
Due to the slope of the channel, erosion is more effective on the downstream side of a meander. Therefore, in addition to growing laterally, the bends also gradually migrate down the valley. Explore This Park. Fluvial Features—Meandering Stream. Due to erosion on the outside of a bend and deposition on the inside, the shape of a meander will change over a period of time.
Erosion narrows the neck of the land within the meander and as the process continues, the meanders move closer together. When there is a very high discharge usually during a flood , the river cuts across the neck, taking a new, straighter and shorter route.
Deposition will occur to cut off the original meander, leaving a horseshoe-shaped oxbow lake.
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