Valley 32416 226168811 2008-07-17T03:31:39Z Wilson44691 4349401 /* Famous valleys */ {{FixHTML|beg}}<!-- Rendering issues in firefox spotted 28 June 2008, fixing "bunching" by photos and displaced edit links, and text "atop pictures" (occurred in wide panoramic pic region, a few sections down from here). * Given relative brevity of this stub, the lower image has lots of space to whitespace issues, so keeping all together so to mitigate that. Hope someone will grow this article a bit. // user:Fabartus --> [[Image:Fljótsdalur.jpg|right|thumb|330px|[[Fljótsdalur]] in East [[Iceland]], a rather flat valley]] [[Image:ValleyProfile3.png|right|330px|thumb|Schematic cross section of a typical valley in the [[Eastern Alps]]. The shoulders of U or V valleys are often located roughly ''halfway up'' the slopes]] [[Image:Glacial Valley MtHoodWilderness.jpg|thumb|right|330px|A glaciated valley in the [[Mount Hood Wilderness]] showing a characteristic U-shape, the bottom's rocky 'rubble' accretion and the broad shoulders]] [[Image:Glacier park1.jpg|right|330px|thumb|U-shaped valley in [[Glacier National Park (U.S.)|Glacier National Park]] in [[Montana]], [[United States]].]] {{FixHTML|end}} :''This article is about the physical-geographic term. For places named "Valley" see [[Valley (disambiguation)]].'' In [[geology]], a '''valley''' (also called a '''vale''', '''dale''', '''glen''' or '''strath''' and near or in [[Appalachia]], a '''Draw''') is a [[Depression (geology)|depression]] with predominant extent in one direction. A very deep river valley may be called a [[canyon]] or '''gorge'''. The terms [[U-shaped valley|U-shaped]] and [[V-shaped]] are descriptive terms of [[geography]] to characterize the form of valleys. Most valleys belong to one of these two main types or a mixture of them, at least with respect of the [[cross section (geometry)|cross section]] of the slopes or hillsides. {{TOCnestright}} == River valleys {{anchor|River valleys}} == <!-- {R to section} redirect target, "[[River valley]]" --> :''For a comprehensive list of world wide river valleys see: [[:Category:River valleys|River valleys (category)]]'' {{see|River phenomenon}} A valley formed by [[River|flowing water]], or ''river valley'', is usually V-shaped. The exact shape will depend on the characteristics of the stream flowing through it. Rivers with steep gradients, as in [[mountain range]]s, produce steep walls and a narrow bottom. Shallower slopes may produce broader and gentler valleys, but in the lowest stretch of a river, where it approaches its [[base level]], it begins to deposit sediment and the valley bottom becomes a [[floodplain]]. A V-shaped valley is formed by [[downcutting]] when the flowing stream erodes its channel at a higher rate than the sides are eroded. The resulting landform is a narrow canyon with fast water and little bank ([[floodplain]]) on the river sides. Some broad ''V'' examples are: * USA: [[Black Canyon of the Gunnison National Park]], and others in [[Grand Canyon National Park|Grand Canyon NP]] * Alpine Europe: ** Austria: narrow passages of upper [[Inn valley]] (Inntal), affluents of [[Enns River|Enns]] a.s.o ** Switzerland: [[Napf]] region, Zurich Oberland, [[Engadin]] ** Germany: affluents to the middle reaches of [[Rhine]] and [[Moselle River|Mosel]] == Glacial valleys == <!-- These two images, especially the last one, just don't work too well here. These moved up to the head end table so will float well with zoom. Expanding the article would help too. It's awfully terse, when much more could be said geologically and geographically, I would imagine. ... {{FixHTML|beg}} [[Image:Glacial Valley MtHoodWilderness.jpg|thumb|right|210px|A glaciated valley in the [[Mount Hood Wilderness]] showing a characteristic U-shape and the broad shoulders]] [[Image:Glacier park1.jpg|right|250px|thumb|U-shaped valley in [[Glacier National Park (U.S.)|Glacier National Park]] in [[Montana]], [[United States]].]] {{FixHTML|end}} ... in-line comment ending ---> A valley carved by [[glacier]]s, or ''glacial valley'', is normally U-shaped. The valley becomes visible upon the recession of the glacier that forms it. When the ice recedes or thaws, the valley remains, often littered with small boulders that were transported within the ice. Floor gradient does not affect the valley's shape, it is the glacier's size that does. Continuously flowing glaciers - especially in the [[ice age]] - and large sized glaciers carve wide, deep incised valleys. Examples of U-shaped valleys are found in every mountainous region that has experienced [[glaciation]], usually during the [[Pleistocene]] [[Ice Age|ice ages]]. Most present U-shaped valleys started as V-shaped before glaciation. The glaciers carved it out wider and deeper, simultaneously changing the shape. This proceeds through the glacial erosion processes of [[glaciation|glaciation]] and [[Abrasion (geology)|abrasion]], which results in large rocky material (glacial till) being carried in the glacier. A material called boulder clay is deposited on the floor of the valley. As the ice melts and retreats, the valley is left with very steep sides and a wide, flat floor. A [[river]] or [[stream]] may remain in the valley. This replaces the original stream or river and is known as a [[misfit stream]] because it is smaller than one would expect given the size of its valley. Other interesting glacially-carved valleys are the * [[Yosemite Valley]] ([[USA]]) * [[Side valley]]s of the Austrian river [[Salzach]] for their parallel directions and hanging mouths. * Some Scottish glens full with bushes and flowers. * That of the [[St. Mary River]] in [[Glacier National Park (United States)|Glacier National Park]] in [[Montana]], USA. {{-}}<!-- Forces table below to adjust to pic count and bottom locii ---> == Transition forms and valley shoulders == {| style="width:auto; max-width:98%;" |<!-- begins right side of table --->[[Image:Paria View at Bryce Canyon NP.jpeg|thumb|right|400px|Look from Paria View to a valley in [[Bryce Canyon]]/Utah with very striking shoulders]]<!-- moved up slightly 28 June 2008, am forcing text and pic inside table so text won't over write pic as I'm seeing in firefox --- User:Fabartus ---> |&nbsp; &nbsp;<!-- Forced padding text to image ---> | <!-- technically, the third column ---> Depending on the [[topography]], the [[rock type]]s and the [[climate]], a lot of transition forms between V-, U- and plain valleys exist. Their bottoms can be broad or narrow, but characteristic is also the type of valley shoulder. The broader a mountain valley, the lower its shoulders are located in most cases. An important exception are [[canyon]]s where the shoulder almost is near the top of the valley's slope. In the Alps - e.g. the [[Tyrol]]ean [[Inn River|Inn]] valley - the shoulders are quite low (100-200 meters above the bottom). Many [[village]]s are located here (esp. at the sunny side) because the [[climate]] is very mild: even in winter when the valley's floor is completely filled with fog, these villages are in [[Sunlight|sunshine]]. |} <!-- Table ends --> In some stress-tectonic regions of the [[Rocky mountains|Rockies]] or the Alps (e.g. [[Salzburg]]) the [[side valley]]s are parallel to each other, and additionally they are [[hanging valleys|hanging]]. The brooks flow into the [[river]] in form of deep [[gorge]]s or [[waterfall]]s. Usually this fact is the result of a violent erosion of the former valley shoulders. A special genesis we find also at [[arête]]s and glacial [[Cirque (landform)|cirques]], at every Scottish glen, or a northern [[fjord]]. == Hanging valleys == [[Image:Closeup of Bridalveil Fall seen from Tunnel View in Yosemite NP.JPG|right|thumb|Bridal Veil Falls in [[Yosemite National Park]] flowing from a hanging valley.]] A '''hanging valley''' is a [[tributary]] valley with the floor at a higher relief than the main channel into which it flows. They are most commonly associated with U-shaped valleys when a tributary [[glacier]] flows into a glacier of larger volume. The main glacier erodes a deep U-shaped valley with nearly vertical sides while the tributary glacier, with a smaller volume of ice, makes a shallower U-shaped valley. Since the surfaces of the glaciers were originally at the same [[elevation]], the shallower valley appears to be ‘hanging’ above the main valley. Often, [[waterfall]]s form at or near the outlet of the upper valley. <ref>{{cite web| title =Glossary of Glacier Terminology| work =| publisher =U.S. Geological Survey| date =[[May 28]], [[2004]]| url =http://pubs.usgs.gov/of/2004/1216/h/h.html| accessdate = 2007-05-24 }}</ref> == Valley floors == Usually the bottom of a main valley is broad - independent of the U or V shape. It typically ranges from about one to ten kilometers in width and is commonly filled with mountain [[sediment]]s. The shape of the floor can be rather [[Horizontal plane|horizontal]], similar to a flat [[Cylinder (geometry)|cylinder]], or [[stream terrace|terrace]]d. [[Side valley]]s are rather V than U-shaped; near the mouth [[clammy|clammies]] are possible if it is a [[hanging valley]]. The location of the [[village]]s depends on the across-valley profile, on [[climate]] and local traditions, and on the danger of [[avalanche]]s or [[landslide]]s. Predominant are places on terraces or [[alluvial fan]]s if they exist. Historic siting of villages within the [[mainstem (hydrology)|mainstem]] valleys, however, have chiefly considered the potential of [[flood]]ing. == Hollows ==<!-- This section is linked from [[A1 road (London)]] --> A '''hollow''' is a small valley or dry [[stream bed]]. This term is commonly used in [[New England]], [[Arkansas]], [[Missouri]] and [[Pennsylvania]] to describe such geographic features. The term is also used in Southern [[Appalachia]], but pronounced "holler." Hollows may be formed by [[river]] valleys such as [[Mansfield Hollow]] or they may be relatively dry clefts with a notch-like characteristic in that they have a height of land and consequent [[water]] divide in their bases. A hollow such as this is [[Boston Hollow]]. Tourists in Europe can further visit a lot of [[karst]], [[stalactite]] and [[ice hollow]]s (e.g. in [[Slovenia]] and [[Austria]]). == Famous valleys == [[Image:2007 0805klklk0017.JPG|thumb|right|250px|A valley in the [[Blue Mountains (Australia)|Blue Mountains]]]] [[Image:Lötschental.jpg|thumb|right|250px|The [[Lötschental]] Valley in the [[Swiss Alps]]]] [[Image:UshapedValleyUT.JPG|thumb|right|250px|U-shaped valley carved by a glacier; Little Cottonwood Creek Valley, [[Wasatch Mountains]], [[Utah]].]] * [[California Central Valley]] (United States) * [[Copper Canyon]] * [[Danube Valley]] (Eastern Europe, [[Wachau]], [[Iron Gate (Danube)|Iron Gate]]) * [[Death Valley]] (California) * [[Glen Coe]] (Scotland) * [[Grand Canyon]] (Arizona) * [[Great Glen]] (Scotland) * [[Great Rift Valley]] (from Jordan to the [[Red Sea]] and [[Lake Victoria]]) * [[Indus Valley]] (Pakistan) * [[Little Cottonwood Creek Valley, Utah]] * [[Loire Valley]] with its famous [[castle]]s (France) * [[Napa County, California|Napa Valley]] (California) * [[Nile Valley]] (Egypt) * [[Okanagan Valley]] (Canada) * [[Owens Valley]] (California) * [[Panjshir Valley]] * Upper [[Rhine Valley]] (an old [[graben]] system) (France) * [[Rhone Valley]] from the [[Matterhorn]] to Grenoble and [[Lyon]] (France) * [[Rio Grande Valley]] (United States) * [[Shenandoah Valley]] (United States) * [[Sonoma Valley]], [[California]], [[United States|USA]] * [[Valley of the Kings]] (Egypt) * [[Valley of the Sun]] (Phoenix, Az, USA) * [[San Fernando Valley]] (California) * [[Santa Clara Valley]], perhaps better known as "[[Silicon Valley]]" (California) * [[South Wales Valleys]] (Wales) * [[Valley of Mexico]] (Mexico), also known as "El Valle de México" see [[Mexico city]] == Rift valleys == {{main|Rift valley}} Rift valleys, such as the [[Great Rift Valley]], are formed by the expansion of the [[Earth]]'s crust due to [[Plate tectonics|tectonic]] activity beneath the Earth's surface. == Extraterrestrial valleys == The other [[terrestrial planet]]s and the [[natural satellites|moons]] of our Solar System can also have valley-like features. [[List of valleys on the Moon|Lunar valleys]] can be formed from a linked chain of [[impact crater]]s. Smaller valleys, known as [[rille]]s, may have originated from [[lava]] flows or from the contractions of cooling lava sheets. Besides the lunar [[Impact crater|craters]], the details of lunar mountain ranges have been well known for more than 300 years (e.g. [[Johann Hieronymus Schröter|J.H. Schröter]]'s ''Selenotopographische Fragmente'' of [[1791]]). A lot of linear phenomena like [[Vallis Rheita|Rheita]] or Schröter valley and the famous [[Vallis Alpes]] (see also below) were observed with details less than 1 km (which corresponds to a coin seen from 5-10 km distance)&mdash;but the geological genesis was debated until the [[Apollo 11]] mission in 1969. [[Astronomer]]s have long been able to observe some [[Highland (geography)|highland]]s and [[mountain]]s on Mars, and therefore guessed that there may be valleys, as well. In the 1970s this interpretation was proven correct by results from [[space probe]]s. Valleys have also been found on [[Mercury (planet)|Mercury]] and on the volcanic surfaces of [[Venus]] and [[Io (moon)|Io]]. The largest valley in our [[solar system]] is the [[Valles Marineris]] formation on [[Mars]]. The ''Valles'' (which were first detected in [[1877]] by [[Martian canals|Schiaparelli]]) are a huge [[canyon]] system spanning 4,500 x 600 km in area and having a depth up to 8 km. These enormous dimensions are 4-8 times greater than those of the American [[Grand Canyon]]. The ''Valles'' is currently understood to have been created by [[plate tectonics|tectonic]] forces like the main [[graben]]s on Earth, rather than by running water. Later, though, it may have been ''expanded'' considerably by erosion, possibly including the action of surface water. [[Ice|Icy]] [[natural satellite|moons]] of the gas planets [[Jupiter]], [[Saturn]] and [[Neptune]] were also photographed by the two [[Voyager program|Voyagers]] as well as by other space probes. Some linear ruptures in the ice or apparent low areas between hills have been interpreted by [[astrogeology|astrogeologists]] as tectonic structures or valleys similar to [[graben]]s or active geologic [[Rift (geology)|rifts]] on Earth. ==See also== [[Image:DirkvdM orosi.jpg|thumb|A view of [[Orosí]], [[Costa Rica]].]] * [[Canyon]], [[Vale]], [[Gorge]], [[Channel (geography)|Channel]], [[Gully]] * [[Clammy]], [[Cliff]], [[Glacial landforms]], [[Side valley]] * [[Geography]], [[Geomorphology]], [[Geodynamics]], [[Glaciology]] * [[Landform|List of landforms]], [[List of mountain ranges]] * [[Geological features of the solar system]], [[List of valleys on the Moon|List of Lunar valleys]] * [[List of mountains on Mars|Martian mountains]], [[List of lineae on Europa|Lineaments on Europa]], [[List of geological features on Titan|Geologic features on Titan]], ([[escarpment]]s and [[rupes|ruptures]]). ==References== <references/>{{-}} {{expand|date=June 2008|Article. The Language is very terse, write for precocious 9-12 y.o.'s and up, not professionals.|full note:Language is very terse, write for precocious 9-12 y.o.'s and up, not professionals. Needs more meat, or take out half the images. |For example, nothing much about physical processes generating a valley. presumable a gulch grows to a gully to a Ravine to a hollow to a small valley. Such and each should be covered in brief imho. | user:Fabartus, copyedit/formatting 28 June 2008 }} == External links == {{Wiktionary|Valley}} * [http://www.nps.gov/brca/geodetect/Landfroms/valleys.htm Univ.of Wisconsin] * [http://dict.leo.org/se?lp=ende&p=5qvU.&search=moraine Glacial moraine types (LEO dictionary)] * [http://www.uwsp.edu/geo/faculty/lemke/alpine_glacial_glossary Glossary of Alpine Glacial Landforms] * [http://www.bgu.ac.il/BIDR/research/phys/remote/Papers/1998-Ichoku_Coherance_IJRS_98.pdf SAR interferometry (analysis of valley forms in Fig.2 and 6)] * [http://www.braggiotourismus.ch/ Shoulder of the Swiss Calanca valley near Braggio] * [http://www.zum.de/Faecher/Ek/BAY/gym/Ek11/tal.htm Typical valley sections (valleys and terrace valleys)] * [http://www.kented.org.uk/ngfl/subjects/geography/rivers/RiverArticles/vshapedvalley.htm V-shaped valley] ===Extraterrestrial valleys=== * [http://www.esa.int/SPECIALS/SMART-1/SEMM7R7X9DE_2.html ESA image]: [[Vallis Alpes]], bisecting the Lunar Alps * [http://www.geoinf.fu-berlin.de/projekte/mars/hrsc152-OphirChasma.php Valles Marineris and Ophir Chasma], [[bilingual]] website ([[English language|English]] and [[German language|German]]) [[Category:Valleys| ]] {{cat also|{{PAGENAME}}|Erosion landforms|Slope landforms | Mountain and glacial landforms | Fluvial landforms}} [[ar:واد]] [[an:Bal]] [[gn:Yvyty pa'ũ]] [[be:Даліна]] [[be-x-old:Даліна]] [[br:Traoñienn]] [[bg:Долина]] [[ca:Vall]] [[ceb:Vallée]] [[cs:Údolí (geomorfologie)]] [[cy:Dyffryn]] [[da:Dal]] [[pdc:Daal]] [[de:Tal]] [[et:Org]] [[es:Valle]] [[eo:Valo]] [[fa:دره]] [[fr:Vallée]] [[gan:谷]] [[ko:계곡]] [[hi:'यू' आकार की घाटी]] [[id:Lembah]] [[it:Valle]] [[he:עמק]] [[lt:Slėnis]] [[nl:Dal]] [[ja:谷]] [[no:Dal]] [[oc:Val]] [[pl:Dolina]] [[pt:Vale]] [[qu:Qhichwa]] [[ru:Долина]] [[simple:Valley]] [[sl:Dolina]] [[fi:Laakso]] [[sv:Dal]] [[te:లోయ]] [[vi:Thung lũng]] [[tr:Vadi]] [[uk:Долина]] [[zh:谷地]]