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Side valleys and tributary valleys are valleys whose brooks or rivers flow into greater ones.
Upstream, the valleys can be classified in an increasing order which is equivalent to the usual orographic order: the tributaries are ordered from those nearest to the source of the river to those nearest to the mouth of the river. A confluence is where two or more tributaries or rivers flow together.
In the orographic classification (order of rivers) the tributary river has order n+1, if n describes the primary (or main) river. A river which flows directly into the ocean (e.g. the English rivers Thames or Humber) has the orographic order n=1, the River Ouse n=2, the Wharfe n=3 and so on.
The term "side valley" is used for higher order valleys near mountains (example above: the Pennines), as opposed to lower valleys that do not have a strong relief. This is because the "main stem river" (into which the secondary river flows) passes much more water than its tributaries and therefore
The higher the order of a valley, the steeper the hillsides. Looking upstream, the steepest slopes are normally near the source of a brook (with the exception of very hard rocks in downstream direction).
The estuary of broad rivers lies in flat regions (river flats) rather than in regions with higher elevation. Therefore, the stream gradient of the tributary near its mouth is small (e.g. 1 m per km), but much more at waters of higher order (in the Alps up to 100 m per km). This is one reason for the large number of hanging valleys in some mountain ranges (e.g. Salzburg or Graubünden).
Glaciologic or geologic reasons:
These stages of valley genesis can be seen in higher mountain ranges - e.g. in the "young" Rocky Mountains, in the "old" ranges and fjords of Scandinavia, or in the Eastern Alps (Salzach or Inn valley).
Sandbanks often occur at reaches with slow current, especially near river banks. Studying the various gravel rock types is an excellent and cheap survey for a summarized geology of the rivers watershed (catchment area).
Generally the main river and tributary are easily identified, as one stream is both longer and carries more water than the other. Occasionally one stream is longer, but the other carries more water. This case offers no fixed rules, but the longer valley is usually chosen as the main valley. In Switzerland the long Alpine Rhine is chosen as the main stream, although the Aar carries more water. The Mississippi River carries more water while the Missouri River is much longer, but is still rated the tributary.
Whereas the valleys near river flats don't have special forms, the shape of alpine valleys depends much more from the former glaciology and of the rock type.
Side- or secondary valleys can be V-shaped or U-shaped. Valley floors vary - from just a few meters up to some 100 m (e.g. Bad Gastein or St. Moritz, where small towns have been developed instead of 1000 or 1500 m altitude).
Some valleys are stepped in longitudinal direction (German "Talstufe") which means that these zones show a quicker current than average. The brook digs its own canal and the eroded sediments are deposed at the end of each clammy, forming a series of local plains. They are an excellent sites for alpine agriculture or pastures.
In earth science, erosion is the action of surface processes that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as physical or mechanical erosion; this contrasts with chemical erosion, where soil or rock material is removed from an area by dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres.
A glacier is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. Glaciers slowly deform and flow under stresses induced by their weight, creating crevasses, seracs, and other distinguishing features. They also abrade rock and debris from their substrate to create landforms such as cirques, moraines, or fjords. Glaciers form only on land and are distinct from the much thinner sea ice and lake ice that forms on the surface of bodies of water.
The Rhine is one of the major European rivers. The river begins in the Swiss canton of Graubünden in the southeastern Swiss Alps, forms part of the Swiss-Liechtenstein, Swiss-Austrian, Swiss-German and then the Franco-German border, then flows in a mostly northerly direction through the German Rhineland and the Netherlands and eventually empties into the North Sea.
A valley is an elongated low area often running between hills or mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers or streams over a very long period of time. Some valleys are formed through erosion by glacial ice. These glaciers may remain present in valleys in high mountain or polar areas. At lower latitudes and altitudes, these glacially formed valleys may have been created or enlarged during ice ages but now are ice-free and occupied by streams or rivers. In desert areas, valleys may be entirely dry or carry a watercourse only rarely. In areas of limestone bedrock, dry valleys may also result from drainage taking place underground rather than at the surface. Rift valleys arise principally from earth movements, rather than erosion. Many different types of valley are described by geographers, using terms that may be global in use or else applied only locally.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
The Kobuk River is a river located in the Arctic region of northwestern Alaska in the United States. It is approximately 280 miles (451 km) long. Draining a basin with an area of 12,300 square miles (32,000 km2), the Kobuk River is among the largest rivers in northwest Alaska with widths of up to 1500 feet and flow at a speed of 3–5 miles per hour in its lower and middle reaches. The average elevation for the Kobuk River Basin is 1,300 feet (400 m) above sea level, ranging from near sea level to 11,400 feet. Topography includes low, rolling mountains, plains and lowlands, moderately high rugged mountainous land, and some gently sloped plateaus and highlands. The river contains an exceptional population of sheefish, a large predatory whitefish within the salmon family, found throughout the Arctic that spawns in the river's upper reaches during the autumn. A portion of the vast Western Arctic Caribou Herd utilize the Kobuk river valley as winter range.
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U-shaped valleys, also called trough valleys or glacial troughs, are formed by the process of glaciation. They are characteristic of mountain glaciation in particular. They have a characteristic U shape in cross-section, with steep, straight sides and a flat or rounded bottom. Glaciated valleys are formed when a glacier travels across and down a slope, carving the valley by the action of scouring. When the ice recedes or thaws, the valley remains, often littered with small boulders that were transported within the ice, called glacial till or glacial erratic.
The Geology of Pennsylvania consists of six distinct physiographic provinces, three of which are subdivided into different sections. Each province has its own economic advantages and geologic hazards and plays an important role in shaping everyday life in the state. They are: the Atlantic Coastal Plain Province, the Piedmont Province, the New England Province, the Ridge and Valley Province, the Appalachian Plateau Province, and the Central Lowlands Province.
The Napeequa River is a 19-mile (31 km) long river in the U.S. state of Washington on the east side of the Cascade Range. It rises in northwest Chelan County and flows southwest into the White River near Twin Lakes. The White River flows into Lake Wenatchee. The Napeequa River and its valley are notable for their beauty and isolation, as well as their interesting geological history. It flows through an isolated southeast-trending valley characterized by a broad meadows surrounded by rugged mountains. The Chiwawa Mountains, or Chiwawa Ridge mark the east side of the valley, separating the Napeequa and Chiwawa Rivers. To the west the White Mountains separate the Napeequa from the White River. Both are sub-ranges of the Cascade Range.
The Nubra River is a river in the Nubra Valley of Ladakh in India. It is a tributary of the Shyok River and originates from the Siachen Glacier, the second-longest non-polar glacier in the world. In earlier Tibetan maps, it was referred as Yarma Tsangpo.
Fluvioglacial landforms are those that result from the associated erosion and deposition of sediments caused by glacial meltwater. These landforms may also be referred to as glaciofluvial in nature. Glaciers contain suspended sediment loads, much of which is initially picked up from the underlying landmass. Landforms are shaped by glacial erosion through processes such as glacial quarrying, abrasion, and meltwater. Glacial meltwater contributes to the erosion of bedrock through both mechanical and chemical processes.
A stream is a body of water with surface water flowing within the bed and banks of a channel. The flow of a stream is controlled by three inputs – surface water, subsurface water and groundwater. The surface and subsurface water are highly variable between periods of rainfall. Groundwater, on the other hand, has a relatively constant input and is controlled more by long-term patterns of precipitation. The stream encompasses surface, subsurface and groundwater fluxes that respond to geological, geomorphological, hydrological and biotic controls.
This glossary of geography terms is a list of definitions of terms and concepts used in geography and related fields, which describe and identify spatial dimension, geographic locations, topographical features, natural resources, and the collection, analysis, and visualization of geographic data. For related terms, see glossary of geology and glossary of environmental science.
Overdeepening is a characteristic of basins and valleys eroded by glaciers. An overdeepened valley profile is often eroded to depths which are hundreds of metres below the deepest continuous line along a valley or watercourse. This phenomenon is observed under modern day glaciers, in salt-water fjords and fresh-water lakes remaining after glaciers melt, as well as in tunnel valleys which are partially or totally filled with sediment. When the channel produced by a glacier is filled with debris, the subsurface geomorphic structure is found to be erosionally cut into bedrock and subsequently filled by sediments. These overdeepened cuts into bedrock structures can reach a depth of several hundred metres below the valley floor.
Lakina River is a tributary of the Chitina River in the U.S. state of Alaska. It is located in the Wrangell–St. Elias National Park and Preserve.
Breakneck Brook, sometimes Breakneck Valley Brook, is a 1.7-mile-long (2.8 km) tributary of the Hudson River located entirely in the Putnam County town of Philipstown, New York, United States. It rises at Surprise Lake and flows southwest towards the Hudson from there, mostly through Hudson Highlands State Park. The name comes from Breakneck Ridge to its north.
Glaciofluvial deposits or Glacio-fluvial sediments consist of boulders, gravel, sand, silt and clay from ice sheets or glaciers. They are transported, sorted and deposited by streams of water. The deposits are formed beside, below or downstream from the ice. They include kames, kame terraces and eskers formed in ice contact and outwash fans and outwash plains below the ice margin. Typically the outwash sediment is carried by fast and turbulent fluvio-glacial meltwater streams, but occasionally it is carried by catastrophic outburst floods. Larger elements such as boulders and gravel are deposited nearer to the ice margin, while finer elements are carried farther, sometimes into lakes or the ocean. The sediments are sorted by fluvial processes. They differ from glacial till, which is moved and deposited by the ice of the glacier, and is unsorted.