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RIVERS

RIVERS. Meanders. A meander is a turning or winding of a stream Incised meanders of Dolores River, Colorado . Meanders. They have single channels that makes big loops Meanders of the Rio Cauto at Guamo Embarcadero , Cuba . Meanders.

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RIVERS

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  1. RIVERS

  2. Meanders A meander is a turning or winding of a stream Incised meanders of Dolores River, Colorado

  3. Meanders • They have single channels that makes big loops • Meanders of the Rio Cauto at Guamo Embarcadero, Cuba.

  4. Meanders Water flows fastest on the outer bend of the river where the channel is deeper and there is less friction. This is due to water being flung towards the outer bend as it flows around the meander, this causes greater erosion which deepens the channel, in turn the reduction in friction and increase in energy results in greater erosion. This lateral erosion results in undercutting of the river bank and the formation of a steep sided river cliff.

  5. Meanders • In contrast, on the inner bend water is slow flowing, due to it being a low energy zone, deposition occurs resulting in a shallower channel. This increased friction further reduces the velocity (thus further reducing energy), encouraging further deposition. Over time a small beach of material builds up on the inner bend; this is called a slip-off slope.

  6. Meanders How a meander grows: http://www.bbc.co.uk/schools/riversandcoasts/rivers/change_river/pg_24_flash.shtml

  7. Meanders

  8. Meanders Formation of an Oxbow Lake

  9. Meanders • Meandering stream with oxbow lake

  10. Meanders An Oxbow Lake http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21606

  11. Meanders

  12. Oxbow Lake Formation Read about how Oxbow Lakes are formed on C10 in your Science book.

  13. Meanders Look carefully at the photo above. Find: • - S-shaped meander • - meander neck • - inside bend of a meander • - outside bend of a meander • - site where erosion might be occurring • - site where deposition might be occurring.

  14. Meanders

  15. Meanders • meanders on the Kanuti River

  16. Meanders

  17. Floodplains When water regularly overflows from a river, it can create a flood plain. A flood plain is a flat land with fertile soil, often found on the banks of rivers.

  18. Floodplains

  19. River Deposition As rivers travel over land it collects nutrients and minerals all the way. When the river ends at a large body of water it drops or deposits all of these minerals, nutrients and sediment. All of this sediment builds up to create a delta.

  20. Delta China’s Yellow River (seen below) is the most sediment-filled river on Earth. The soil is easily eroded, and millions of tons of it are carried away by the river every year. Some of it reaches the river’s mouth, where it builds and rebuilds the delta.

  21. Meanders • http://images.google.com/imgres?imgurl=http://www.geo.umn.edu/courses/1001/Summer_Session/Oxbow.jpg&imgrefurl=http://www.geo.umn.edu/courses/1001/Summer_Session/CourseReview.htm&usg=__Plt1BEH9E_3Y_ISAy1jeYnDOBzg=&h=377&w=944&sz=126&hl=en&start=18&sig2=fVe0VBt_zFK1W_ytpWUIGQ&tbnid=i-yfBB8ezD_GyM:&tbnh=59&tbnw=148&ei=w8U-SbKiJ56eecPXrckM&prev=/images%3Fq%3Dox%2Bbow%2Blake%26hl%3Den%26safe%3Dactive%26rlz%3D1T4GGLL_en • http://en.wikipedia.org/wiki/Meander • http://images.google.com/imgres?imgurl=http://cgz.e2bn.net/e2bn/leas/c99/schools/cgz/accounts/staff/rchambers/GeoBytes%2520GCSE%2520Blog%2520Resources/Images/Rivers/Meander_bend.jpg&imgrefurl=http://geobytesgcse.blogspot.com/2006_11_01_archive.html&usg=__Kc438wM3k5cBcd-I3XarIYlludM=&h=378&w=491&sz=59&hl=en&start=10&sig2=WQApqob3yY4Hmx2Pa4EiTw&um=1&tbnid=fo8QdobnQjSrKM:&tbnh=100&tbnw=130&ei=WAs_SYiQGIKJmQf5-MTpDA&prev=/images%3Fq%3Dmeanders%26um%3D1%26hl%3Den%26rlz%3D1T4DKUS_enUS252US253%26sa%3DX • http://images.google.com/imgres?imgurl=http://www.naturephoto-cz.com/photos/sevcik/meanders--meandry.jpg&imgrefurl=http://www.naturephoto-cz.com/meanders:air-photo-2109.html&usg=__sOfMtEUHjNBsW6KZ6HU43wh9acM=&h=398&w=600&sz=81&hl=en&start=1&sig2=3splDO2fc2EvtAfKHzsmBA&um=1&tbnid=MXbqyWYeUonuKM:&tbnh=90&tbnw=135&ei=WAs_SYiQGIKJmQf5-MTpDA&prev=/images%3Fq%3Dmeanders%26um%3D1%26hl%3Den%26rlz%3D1T4DKUS_enUS252US253%26sa%3DX • http://images.google.com/imgres?imgurl=http://www.stacey.peak-media.co.uk/Year7/7-7Rivers/7-7Meanders/341.jpg&imgrefurl=http://www.stacey.peak-media.co.uk/Year7/7-7Rivers/7-7Meanders/7-7Meanders.htm&usg=__fMHu5RlEiZ_YyAF6fN6GTA5v1ds=&h=471&w=340&sz=50&hl=en&start=4&sig2=5uOQb7kYlZsuRvuGsVW5iw&um=1&tbnid=OSUyXRhtLWE_dM:&tbnh=129&tbnw=93&ei=WAs_SYiQGIKJmQf5-MTpDA&prev=/images%3Fq%3Dmeanders%26um%3D1%26hl%3Den%26rlz%3D1T4DKUS_enUS252US253%26sa%3DX • http://images.google.com/imgres?imgurl=http://www.geo.wvu.edu/~jtoro/geol101/streams/meanders.jpg&imgrefurl=http://www.geo.wvu.edu/~jtoro/geol101/Outline-3.html&usg=__b9d3pF46zVierUeC6Kvohgp9UcE=&h=719&w=959&sz=81&hl=en&start=8&sig2=1P_--4S95JpiBolXlR7w4Q&um=1&tbnid=0FK9_ML-QrPs4M:&tbnh=111&tbnw=148&ei=WAs_SYiQGIKJmQf5-MTpDA&prev=/images%3Fq%3Dmeanders%26um%3D1%26hl%3Den%26rlz%3D1T4DKUS_enUS252US253%26sa%3DX • http://www.gly.uga.edu/railsback/FieldImages/ElkCreekMeanders.jpeg

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