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Oxbow lake

An oxbow lake is a U-shaped lake that forms when a wide meander of a river is cut off, creating a free-standing body of water. This landform is so named for its distinctive curved shape. In Australia, an oxbow lake is called a billabong, from the indigenous Wiradjuri language. In south Texas, oxbows left by the Rio Grande are called resacas; the word "oxbow" can refer to a U-shaped bend in a river or stream, whether or not it is cut off from the main stream. There has been a possible oxbow lake postulated in Saraswati Flumen near Ontario Lacus on Saturn's moon, Titan. An oxbow lake forms. After a long period of time, the meander becomes curved, the neck of the meander becomes narrower and the river cuts through the neck during a flood, cutting off the meander and forming an oxbow lake; when a river reaches a low-lying plain in its final course to the sea or a lake, it meanders widely. In the vicinity of a river bend, deposition occurs on the convex bank. In contrast, both lateral erosion and undercutting occur on the cut concave bank.

Continuous deposition on the convex bank and erosion of the concave bank of a meandering river cause the formation of a pronounced meander with two concave banks getting closer. The narrow neck of land between the two neighboring concave banks is cut through, either by lateral erosion of the two concave banks or by the strong currents of a flood; when this happens a new, straighter river channel develops—and an abandoned meander loop, called a cutoff, forms. When deposition seals off the cutoff from the river channel, an oxbow lake forms; this process can occur over a time from a few years to several decades, may sometimes become static. Gathering of erosion products near the concave bank and transporting them to the convex bank is the work of the secondary flow across the floor of the river in the vicinity of a river bend; the process of deposition of silt and gravel on the convex bank is illustrated in point bars. River flood plains that contain rivers with a sinuous platform are populated by longer oxbow lakes than those with low sinuosity.

This is because rivers with high sinuosity have larger meanders, greater opportunity for longer lakes to form. Rivers with lower sinuosity are characterized by fewer cutoffs and shorter oxbow lakes due to the shorter distance of their meanders; the effect of the secondary flow can be demonstrated using a circular bowl. Fill the bowl with water and sprinkle dense particles such as sand or rice into the bowl. Set the water into circular motion with one hand or a spoon; the dense particles sweep into a neat pile in the center of the bowl. This is the mechanism that leads to the formation of point bars and contributes to the formation of oxbow lakes; the primary flow of water in the bowl is circular and the streamlines are concentric with the side of the bowl. However, the secondary flow of the boundary layer across the floor of the bowl is inward toward the center; the primary flow might be expected to fling the dense particles to the perimeter of the bowl, but instead the secondary flow sweeps the particles toward the center.

The curved path of a river around a bend makes the water's surface higher on the outside of the bend than on the inside. As a result, at any elevation within the river, water pressure is greater near the outside of the bend than on the inside. A pressure gradient toward the convex bank provides the centripetal force necessary for each parcel of water to follow its curved path; the boundary layer that flows along the river floor does not move fast enough to balance the pressure gradient laterally across the river. It responds to this pressure gradient, its velocity is downstream and across the river toward the convex bank; as it flows along the floor of the river, it sweeps loose material toward the convex bank. This flow of the boundary layer is different from the speed and direction of the primary flow of the river, is part of the river's secondary flow; when a fluid follows a curved path, such as around a circular bowl, around a bend in a river or in a tropical cyclone, the flow is described as vortex flow: the fastest speed occurs where the radius is smallest, the slowest speed occurs where the radius is greatest.

The higher fluid pressure and slower speed where the radius is greater, the lower pressure and faster speed where the radius is smaller, are all consistent with Bernoulli's principle. Notable examples Bole and Burton Round in West Burton, England are a good example of previous lakes in a close proximity to one another. Carter Lake, Iowa was created after severe flooding in 1877 led to the river shifting 1.25 mi to the southeast. Cuckmere Haven in Sussex, England contains a meandering river with many oxbow lakes referred to in physical geography textbooks. Half Moon Lake in downtown Eau Claire, Wisconsin was formed due to a shift in the course of the Chippewa River, which now flows to the south. Kanwar Lake Bird Sanctuary, India contains rare and endangered migratory birds and is one of Asia's largest oxbow lakes; the Oxbow, a 2.5-mile bend in the Connecticut River, is disconnected at one end. There are many oxbow lakes alongside its tributaries; the largest oxbow lake in North America, Lake Chicot, was part of the Mississippi River, as was Horseshoe Lake, the namesake for the town of Horseshoe Lake, Arkansas.

Reelfoot Lake in west Tennessee is another notable oxbow lake.

Solina Dam

The Solina Dam is the largest dam in Poland. It is located in Solina of Lesko County in the Bieszczady Mountains area of south-eastern Poland; the San river which runs through the area has a large flood plain and a series of floods prompted the consideration of a dam to regulate the water flow. The first plans for a dam in the region called for a small dam in Myczkowce; the project was slow to begin and with the start of World War II it was put on hold. After the war ended the plans now included a larger dam in Solina. Various work began in 1953 and the smaller Myczkowce Dam downstream, which would become a supporting dam, was completed in the years 1956-1960. In 1960 work began based on a design by Feliks Niczke of Energoprojekt Warszawa; the construction cost 1.5 billion of 1969 zlotys. 57 km of roads were constructed as part of the project. The dam is 664 m long, 8.8 m wide at the crest, 81.8 m high. Its construction created the largest artificial lake in Poland - Lake Solina, it has four turbines which were capable of generating 136 MW of electricity.

As a pumped-storage power station, two of the turbines can reverse flow and send water from the Myczkowce Dam's reservoir back into the Lake Solina for use during peak periods, optimizing power generation. Starting in 1995 efforts have been made to modernize the power plant; the installation of new technologies between 2000 and 2003 and the replacement of the old turbines resulted in the dam generating 200 MW of electricity as opposed to 173 MW previously. The Solina dam is an important tourist attraction of the area. Tours are available and the dam serves as a bridge to the Lake Solina marina. Renewable energy in Poland Media related to Solina Dam at Wikimedia Commons

The World Is in My Hands

"The World Is in My Hands" is a song written by Yann Peifer, Manuel Reuter and Andres Ballinas and recorded by German dance act Cascada. The track was confirmed as the third and final single taken from their latest compilation album “The Best of Cascada”, released on digital retailers on March 29, 2013 via Zooland Records; the music video was premiered on the Universal Music page on July 19 with the single being released worldwide on August 2. The song is included on a number of compilation albums, including: Ministry Of Sound - Ibiza Annual 2013, Future Trance 65, Techno4ever.fm - Sensation Dance! Vol 2, Ballermann Hits Party 2014 The music video was premiered on Universal Music webpage on 19 July 2013. Zooland Records published the video via YouTube on 24 July 2013; the video starts with a young boy playing a piano in a large empty room, as Natalie wanders through, singing to the camera and leaning against the brick wall. There is interjecting dancers in a tunnel. Towards the end of the video, the dancers join Natalie in the room, dance behind her as she finishes the song.

From Discogs. Official Cascada site