Oceans and land are different layers of the Earth. There are several points and places in these layers that are formed naturally due to some changes in them. You must have heard about whirlpools in oceans that are formed naturally. Similarly, there is this meander loop. Have you heard about it? Well, today you will see what is an abandoned cutoff meander loop. Along with what is the cut-off part of a river called and what happens when a meander gets cut off? Let’s begin and find the answers.
1. What is meant by Meander?Photo by Dan Meyers on Unsplash
One of the series of regular curves in a river channel or any other watercourse is known as a meander. In simple words, the curvy path of the river has several curves, and they are termed meanders. They have the appearance of a horse-shoe, and they mostly travel downstream. For example, the Rio Cauto has meanders spread over a large area. (See What are Parts of a River System?)
2. How are Meanders formed?
They are formed when the water flows through a curved channel, with the river bed underlying it. This water motion forms helicoidal flow, which is a flow from a corkscrew. This leads to the water flow to and from the outer bank towards the inner bank along the river bed. This motion causes the rapid deposition and withdrawal of the sediments on the riverside. (See How has the Removal of Wetlands Impacted Rivers and Streams?)
3. What is Meander Cut Off?
Sometimes the hoops of the meanders are close to each other, such that the other curve seems to be just beside one curve. This is the place where the cut-off takes place. The natural cutting or cut in a river, when the previous hook or meander in the river is covered by the water that connects those closest parts of the meander, is termed a meander cut-off. As the cutting happens, it forms a full loop, which is a lake in itself. You are close to knowing what is an abandoned cutoff meander loop. (See What is the Largest Saltwater Lake in the World?)
4. What is the Cut Off Part of a River called?
The cut-off part is the part from where the loop is shortened, making a straight course of the stream or river. This part or portion is termed a chute or cut-off. It mostly occurs due to the lateral erosion of the bank of the upstream arm in a meander loop. There are two types of cutoff channels, namely neck cutoff, and chute cutoff.
- Chute Cutoff: When the channel is cut off directly across the land by bypassing the entire meander loop in the river, it is termed a chute cutoff. In this, the river is totally abandoned.
- Neck Cutoff: This cutoff is formed after a river bend intersects itself. This happens towards the outer bends of the river, as the speed of the water flow is the fastest there. The land between the adjacent outer bends will be eroded away by the river. This will bring them closer, forming the neck cutoff intersection.
5. What is an Abandoned Cutoff Meander Loop?
After creating the flood plain, as the meanders from side to side erode, it will create a broad flat area on both sides of the river. This will lead to the cutoff of the meander from the rest of the river. So, what is an abandoned cutoff meander loop called? This newly formed lake or better say abandoned cutoff meander loop is termed an oxbow lake. It is a U-shaped pool or lake that is formed in different rivers of the world. The term oxbow is used to refer to the U-shaped bend, even when the loop is not cut off from the main river. (See Is Sundarban the Largest Delta in the World?)
6. What happens when a Meander gets Cut Off?Photo by Dan Meyers on Unsplash
As you are aware of what is an abandoned cutoff meander loop, note that sometimes the meander loops are not cut off naturally but it’s done manually, and this leads to the formation of artificial oxbow lakes. This is done to improve navigation or to alleviate the flood. For example, one artificial oxbow lake was formed on the upper Rhine, Germany, in the 19th century. Another example is the Oxford Canal in England. (See What are the Rivers that flow South to North?)
7. How are Oxbow Lakes beneficial to the River?
The water in the oxbow lakes is not continuously in motion because, as it is formed, the flow shifts straight. This calm region of the river helps in improving the health of the river as it traps the sediments and agricultural runoff. This way, these sediments are removed from the main river flow, but this destroys the habitat of oxbow lake itself. (See Which River is Smallest in the Length?)
8. What are Some Examples of Oxbow Lake?
After learning about what is an abandoned cutoff meander, take a look at some notable ones:
- Bole and Burton Round: This is an example of an oxbow lake which is in the West Burton, Nottingham shire in England.
- The Oxbow: It is a bend in the Connecticut River about four kilometers (2 and 1/2 miles) and disconnected at the end.
- Cuckmere Haven: It is a meandering river in Sussex, England.
- Carter Lake: This Oxbow Lake was formed in 1877 after severe flooding in Iowa that led to about a 2 kilometers (1 and 1/4 miles) shift in the river towards the southeast.
- Halfmoon Lake: It was formed after a shift in the course of the Chippewa River in Eau Claire, Wisconsin. Now the river flows towards the south.
- Taieri River Oxbow: It is a series of Oxbow lakes at the upper reaches of the Taieri River, Paerau in New Zealand.
9. How many Oxbow Lakes does the Mississippi River have?Photo by le Sixième Rêve on Unsplash
It is pretty interesting to know about these lakes after knowing about what is an abandoned cutoff meander loop. While there are several oxbow lakes wherever the situation is in favor of their formation. A number of oxbow lakes are found along the river and its tributaries, and some of them are specially mentioned whenever referring to oxbow lakes.
- North America has the largest Oxbow Lake, which is formed from the meanders in Lake Chicot, near the Lake Village in Arkansas.
- Another one is Horseshoe Lake which is formed from the Mississippi River in Arkansas.
- In Tennessee, there is another Oxbow Lake named Reelfoot Lake, which was formed back in 1811 to 1822 after the Mississippi River changed its channel. This probably happened as an after-effect of the New Madrid earthquakes
So today you learned about what is an abandoned cutoff meander loop. Now you know about what is the cut off part of a river called, as well as about its types. You can now answer this tricky question about what happens when a meander gets cut off. If you find this piece informative, share it with your friends and let them know about this part of nature. (See Types of Rivers and Facts)