As water travels around the curve, it flows faster on the outside of the curve and slower on the inside of the curve. This has two effects. The water on the outside of the curve eats away at the river bank in a process called erosion. The water on the inside of the curve, on the other hand, moves more slowly and leaves behind dirt, sand, silt, and other types of sediments in a process called deposition.
Over time, these processes create a curve with a distinct U or crescent shape. As the processes of erosion and deposition continue, the piece of land at the narrow ends of the curve closest to the straight path of the river gets smaller and smaller. Eventually, the river cuts a new, straight path through that small piece of land, creating a shortcut that straightens the path of the river and leaves an oxbow lake behind.
When you look at a photograph of an oxbow lake from above, you can often see how it used to be simply a bend in the river. Cut off from the main river channel , oxbow lakes don't have any water flowing into or out of them. Without sufficient rain, they may dry up completely. Many oxbow lakes that do receive some rain turn into swamps that become thriving wildlife habitats. Are you ready to go for a swim?
Dive into the following activities with a friend or family member:. Hi, mary! Thanks for stopping by. If you still have questions, be sure to submit them to our Wonder Bank! Great question, bassem! There is a good chance that animals would move away--and toward a water source--if a lake dried up. In the case of an oxbow lake, they wouldn't need to move far because the river would be close by! We are undergoing some spring clearing site maintenance and need to temporarily disable the commenting feature.
Thanks for your patience. Drag a word to its definition. You have answered 0 of 3 questions correctly and your score is:. Want to add a little wonder to your website? Help spread the wonder of families learning together. Over time, continual erosion and deposition narrows the neck of the meander. Often during a flood the river will cut through the neck of the meander. The Mississippi River is shorter now than it was in the 19th century, for instance, because engineers have cut off hundreds of meanders.
This created hundreds of oxbow lakes. These lakes eventually dried up to create acres of land for farming, housing, and industry. An oxbow lake gets its name from the U-shaped collar placed around an ox s neck to which a plow is attached. It can also be called a horseshoe lake, a loop lake, or a cutoff lake. Billabong In Australia, oxbow lakes are called billabongs. A billabong is the setting for the unofficial national anthem of Australia, Waltzing Matilda.
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Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. The neck of the meander gradually gets narrower and narrower.
This leaves a separated area of water, called an oxbow lake. Take the rocking rivers quiz! As a river reaches flatter land, it begins to twist and turn. It flows more slowly around the inside of the bend. Over time, sediment seals the end of the old loop.
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