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Meanders. 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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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 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.
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.
Meanders How a meander grows: http://www.bbc.co.uk/schools/riversandcoasts/rivers/change_river/pg_24_flash.shtml
Meanders Formation of an Oxbow Lake
Meanders • Meandering stream with oxbow lake
Meanders An Oxbow Lake http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21606
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.
Meanders • meanders on the Kanuti River
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