Another name for dry riverbeds?
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"wadi"\ngully or streambed in northern Africa and the Middle East that remains dry except during rainy season
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Missouri River\n\nArkansas River (in Kansas it's pronounced "ar-KAN-sus," not "AR-kun-saw")\n\nNeosho River\n\nRepublican River\n\nand others:\nhttp://en.wikipedia.org/wiki/Category:Rivers_of_Kansas
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Yes, there are also some tidal rivers.  The Danube is one I can think of.
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f.r.i.e.n.d.s\nDawson Creek
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flatbeds,\ndouble drop,\ntankers,\nreefers,\npups,\nvans,
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they are forms of water or precipitation
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Traditionally river systems have been classified according to their stage of development as young, mature, or old. The young river is marked by a steepsided valley, steep gradients, and irregularities in the bed; the mature river by a valley with a wide floor and flaring sides, by advanced headward erosion by tributaries, and by a more smoothly graded bed; and the old river by a course graded to base level and running through a peneplain, or broad flat area. The age classification of rivers is diminishing in popularity now that quantitative studies of river behavior are more common.
4343
One really long disconnected river.
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tan, odd, old, pot, shy, big, wet, dry, ice, low
922456
It is called a meander or an oxbow.  Wikipedia has a good explanation.
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Oh! Deltas! Estauries are sunken river mouths. Good examples: China's Pearl River Delta, Argentina's La Plata, Maryland's Chesapeake Bay.\n\nBird's foot or digitate, that's where the river branches out at the mouth. Nile River Delta, the classic. Niger River Delta, and Mississippi Delta. \n\nArcuate. Hmmmm...I'm guessing it's roundish, but...I'm going to have to look it up! Yes, it's arc shaped, and the Ganges Delta is an example. Darn it! The Nile is, too! Oooh! Nice photo illustrating the Nile Delta article! Oh the Niger delta is, too! Guess that leaves the Mississippi Delta as a bird's foot!
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The main parts of a river include a channel, in which the water flows, and a floodplain—a flat region of a valley on either side of the channel. Through the channel and floodplain, water and sediment—material transported by the river, such as sand and silt—are transferred from ridges and mountains to the sea or to a lake. A river starts on hillsides as small channels, or rills. The rills combine to make larger channels or tributaries that eventually come together, forming distinct streams. The largest channels formed by this convergence of tributaries are rivers, and they can carry large quantities of fresh water and sediment across continents.
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whats  the  bed  like...i 'm guessing   river....if its  not  firm....NO...don"T  GO....how  fast  is  it  moving?.......in a  flash flood  situation...it  may  be  shallow  but  the  force could  knock  yr  feet  out from  under  you.........if yr  explorin....have a  guide  and  equipement....evalu ate...many  times  i've  camped  out   waited  to  let  the  water  go down....again....whats  under it.....why  go?....plan  B..can you  swim?
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Earth has many old dried up river valleys.
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Agricultural run-off\nBeavers (very dirty animal) or other infectious or unsanitary creatures.\nChemical spill/run-off\nnoxious substances in an en route stream
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I don't think there's a technical term for it.\n\nI like 'bobs'. I live in the southeast US where it doesn't snow much, but rest assured, when it does there will be bobs everywhere.\n\nHey, when they get dirty, will they be dirtybobs?
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If you mean river rapids: water traveling from a higher to a lower elevation over obstacles.  The obstacles cause turbulence in the water called rapids.  Variables are: water volume; rate of elevation drop; size/number of obstacles.