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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If a media asset is downloadable, a download button appears in the corner of the media viewer. If no button appears, you cannot download or save the media. Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. Of that, only about 1. Most of our drinking water comes from rivers and streams. This water is the lifeline of ecosystems around the world. Erosion is the process where rocks are broken down by natural forces such as wind or water.
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. Media Credits 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.
Last Updated June 10, Media If a media asset is downloadable, a download button appears in the corner of the media viewer. Text Text on this page is printable and can be used according to our Terms of Service. 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. The river carries sediment, which contains particles of rock and sand, as it flows toward the sea. The slow moving water drops sediment on the inner bank. This is called deposition. Over time, this action makes the curve get bigger and turns it into a meander. Continuing erosion and deposition tighten the curve of the meander into a C-shaped loop.
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