This site uses cookies and by continuing to browse it you are agreeing to our use of cookies. Read our cookies policy. As a river reaches flatter land, it swings from side to side, forming winding bends called meanders. The water flows fastest around the outside of the bend, and slower on the inside.
The speed of the flow cuts away the outside bank of a loop in a process called erosion. At the same time, it drops sediment, which contains particles of rock and sand, on the inner bank in a process called deposition. This causes the meanders to become grow bigger and bigger over time. Eventually the river may take a short cut, cutting across the narrow neck of the loop, leaving a separated U-shaped lake known as an oxbow.
This animation shows how an oxbow lake is formed, step by step. The water flows fastest around the outside of the bend. The fast-flowing water cuts away the outer bank. This is called erosion. People often create oxbow lakes. 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. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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There are two main types of erosion: chemical and physical. In physical erosion, the rock breaks down but its chemical composition remains the same, such as during a landslide or bioerosion, when plants take root and crack rocks.
Explore the process of erosion with this collection of resources. Freshwater is a precious resource on the Earth's surface. It is also home to many diverse fish, plant, and crustacean species. The habitats that freshwater ecosystems provide consist of lakes, rivers, ponds, wetlands, streams, and springs.
Use these classroom resources to help students explore and learn about these places. A lake is a body of water that is surrounded by land. There are millions of lakes in the world. Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Twitter Facebook Pinterest Google Classroom.
Encyclopedic Entry Vocabulary. The swampy remains of an oxbow lake are evident in the jungle surrounding the Ramu River in Papua New Guinea. Photograph by James P.
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