What is a river valley?
600189
Water (rain, snow, dew, ...) which ends up higher than sea level will flow toward the sea if there is any possible path. Since even a mountainous 'bowl' is likely to have a porous bottom, or to fill enough to find an outlet, there will almost always be a flow to lower levels. \n\nFlowing water is not a neglibible force. It will, over geologic time move, dissolve, pulverize, and remove material. Freeze/thaw cycles contribute more than a bit; the Old Stone Face in new Hampshire in N America has recently fallen (literally) to this. Some of that material will be dropped downstream, filling in an existing channel. Spring floods (in places in which snow and ice accumulate on high ground) will provide an annual increase in this erosion, and if they break over channel banks, will accelerate the deposition process (eg, the Nile floods until the installation of dams to stop them). \n\nOver geologic time, a stream (or river) will fill channels repeatedly and will find new flow paths after doing so. What with dumping material from higher levels, and doing it in channels here and there across the gap between highlands, there will be a gradual acretion of soil in that gap. \n\nEventually, the flowing water, combined on occasion with wind and plant and animal soil processing (earthworms, for instance), there will be a more or less level filiing of the gap between highlands, with water flowing across it on the way to the sea. \n\nThat space, with a history more or less as sketched is a valley. Tehy can be narrow (a kilometer or less) or wide (several hundred kilometes). In fact, they can be so wide that it's not possible for a human to see both highlands between which the water flows at the same time. Valleys can also be very long if the highlands are arranged to permit. Consider the Nile, the Danube, the Volga, the Mississippi, or the Ganges. \n\nIn short, highlands erode, flatten out, and fill in the gaps between them. This can be seen in Britain (whose hills and mountains wer once higher) and in the North American Appalacians (whcih were once very very impressively tall). The N American Rockies, S American Andes, and Asian Himalyas are examples of the early stages in this process. Some millions of years hence, all three of these mountain ranges will be much lower and rounder.
375240
There's a page that covers this here (http://www.urbanedpartnership.org/target/units/river/tour/hist.html)
704993
In a van down by the river ....getting h-i-g-h LOL
442402
The mouth.\nLakes,streams from mountains.The ice from mountains melt,causing tiny streams of water running down the mountain.As it goes along,more water is collected(rain etc.),and it becomes a small river.There are three stages of a river.First,the valley is narrow,second,it gets wider,and third, it is almost flat and very wide.it ends at the sea. \nHope this helps :)
821548
Delta\nA delta is a landform where the mouth of a river flows into an ocean, sea, desert, estuary or lake, building outwards (as a deltaic deposit) from sediment carried by the river and deposited as the water current is dissipated. Deltaic deposits of larger, heavily-laden rivers are characterized by the river channel dividing into multiple streams (distributaries), these divide and come together again to form a maze of active and inactive channels\n\n Estuaries\nEstuaries are aggrading depositional sedimentary bodies at the mouths of rivers. Many present river mouths became estuaries after the post-glacial sea-level rise inundated the former deltas. When that happened, fluvial channels became subject to tidal influence. Especially in meso- and macro-tidal regimes, the fluvial processes became subordinate to marine redistribution and tide-dominated estuaries could form.
104013
river\n\nn : a large natural stream of water (larger than a creek); \n\nIf it didn't have water, I don't think it would be called a river.
115081
a tributary or a distub thingy
70354
because it has river banks
221875
A small secluded wooded valley
587663
i live in edmonton and i love the river valley especially.\nso many trails for walking and riding i recommend anyone who comes here to try it.bike riders like myself love going from one end of the city to the other.
445121
you'd probably have better luck if you specified which river valley.
545855
go to google and type in bhara river basin and it will give you a choice of sites on that subject.hope this helps!
1162715
i love Hiking! The Kady Trail in Missouri/Illinois area. Great view of the river!!
982093
Also called "misfit river"--river is much smaller than expected for the width of its valleys--very common in areas that were once glaciated.  \nIn the United States and Canada, several rivers are much smaller now  than when they  received vast outflow of water from glacial melts during the Ice Ages when there were vast continental glaciers covering Canada and the Great Lakes area. So, during Pleistocene time, the river systems cut wide valleys that seem not to "fit" the current volume of water flowing through the rivers. \nMinnesota River: "Some 9,000 to 12,000 years ago, the Glacial River Warren flowed with great volumes of meltwater from the southern end of the Glacial Lake Agassiz. Those icy currents carved the wide, trough-like, loam-covered valley of the Minnesota River that we see today."\nhttp://www.environmentaleducationohio.org/Biosphere/Case%20Studies/minnesota.html\nMilk River: "Most of the canyon cutting took place when virtually all of the runoff from southwestern Alberta was being diverted into the Milk River as a result of blockage by ice of drainage to the northeast. With recession of the Laurentide glacier out of the region and opening of a route around the Cypress Hills, evolution of the modern South Saskatchewan drainage began, waters that previously were feeding the Milk River became incorporated into the Hudson Bay catchment basin" (Beaty, 1975)." http://www.uleth.ca/vft/milkriver/milk_river.html\nIllinois River:"the old valley is exceptionally wide for the size of the new river. After the last glacier retreat ed, the Illinois permanently shrank to a much smaller river, fed only by rainfall and seepage from underground aquifers. The pulse of the river changed. In years with average rainfall, backwater lakes rose and expanded, temporary ponds developed, and grass lands became marshes in late winter and early spring. The water then drained out slowly; by midsummer the river flowed only in the main channel and much of the floodplain was dry again. "\nhttp://dnr.state.il.us/orep/c2000/assessments/lower_sangamon/page4.htm.\nUpper Mississippi River.\n\nYou can imagine drought, stream capture, and similar phenomenon causing a decline in flow.
156133
<A canyon, or gorge, is a valley walled by cliffs. Most canyons originate by a process of long-time erosion from a plateau level, with a stream gradually carving out its valley. The cliffs form because harder rock strata that are resistant to erosion and weathering remain exposed on the valley walls. Canyons are much more common in arid areas than in wetter areas because weathering has a lesser effect in arid zones. Canyons' walls are often formed of resistant sandstones or granite. Submarine canyons are those which form underwater, generally at the mouths of rivers.
386599
A river is the main body of water, the tributaries are smaller streams etc that branch off it or into it...\n\nLike a tree... the trunk is the river, the branches are tributaries..
1141476
A delta usually forms near a river's mouth, the place where the river meets a large body of water, because some of the sediments that the river picks up upriver are brought to the mouth, where there is little to no resistance. This is the reason why deltas can only form near the mouth of a river. Then, the sediments settle at the mouth of the river and pile up. After hundreds or thousands of years, this process eventually forms a delta. Deltas are named so because they look like the Greek letter delta, which is shaped like a triangle.