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Tidal Reach
A reach is a segment of a stream, river, or arm of the sea, usually suggesting a straight, level, uninterrupted stretch. They are traditionally defined by the capabilities of sailing boats, as a stretch of a watercourse which, because it is straightish, can be sailed in one reach (that is, without tacking). Reaches are often named by those using the river, and a reach may be named for landmarks, natural features, and historical reasons (see, for instance, Gallions' Reach, named after the family that once owned its banks). A reach may be an expanse, or widening, of a stream or river channel. This commonly occurs after the river or stream is dammed. A reach is similar to an arm, though an arm may bend and thus have multiple reaches. The term "reach" can also refer to a level stretch, as between river rapids or locks in a canal. The word may also be used more generally to refer to any extended portion or stretch of land or water, or even metaphorically. In fluvial hydrology, a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arm (geography)
In geography, an arm is a narrow extension, inlet, or smaller reach, of water flowing out from a much larger body of water, such as an ocean, a sea, or a lake. Although different geographically, a sound or bay may also be called an arm. Both the tributary and distributary of a river are sometimes called an "arm". By extension, a ''canal arm'' is a subsidiary branch of a canal or inland waterway. See also *River *Channel *Indian Arm *Alice Arm *Gulf of Bothnia The Gulf of Bothnia (; fi, Pohjanlahti; sv, Bottniska viken) is divided into the Bothnian Bay and Bothnian Sea, and it is the northernmost arm of the Baltic Sea, between Finland's west coast ( East Bothnia) and the Sweden's east coast (West ... Coastal and oceanic landforms Bodies of water {{Topography-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hanford Reach National Monument
The Hanford Reach National Monument is a national monument in the U.S. state of Washington. It was created in 2000, mostly from the former security buffer surrounding the Hanford Nuclear Reservation. The area has been untouched by development or agriculture since 1943. Because of that it is considered an involuntary park. The monument is named after the Hanford Reach, the last non-tidal, free-flowing section of the Columbia River in the United States, and is one of eight National Monuments administered by the U. S. Fish and Wildlife Service; part of the monument within the Hanford Site is also managed by the Department of Energy. President Bill Clinton established the monument by presidential decree in 2000. In May 2017, the Interior Department announced that Hanford Reach was one of 27 National Monuments under review for possible rescinding of their designation. Ancestors of the Wanapum People, Yakama Nation, Confederated Tribes of the Colville, Confederated Tribes of the Uma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rivers
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as creek, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, but not always: the language is vague. Rivers are part of the water cycle. Water generally collects in a river from precipitation through a drainage basin from surface runoff and other sources such as groundwater recharge, springs, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial Landforms
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used. Fluvial processes Fluvial processes include the motion of sediment and erosion or deposition on the river bed. The movement of water across the stream bed exerts a shear stress directly onto the bed. If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose sediment which can be mobilized by such stresses, then the bed will be lowered purely by clearwater flow. In addition, if the river carries significant quantities of sediment, this material can act as tools to enhance wear of the bed ( abrasion). At the same time the fragments themselves are ground down, becoming smaller and more rounded (attrition). Sediment in rivers is transported as either bedload (the coarser frag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Geography
Physical geography (also known as physiography) is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, hydrosphere, biosphere, and geosphere. This focus is in contrast with the branch of human geography, which focuses on the built environment, and technical geography, which focuses on using, studying, and creating tools to obtain,analyze, interpret, and understand spatial information. The three branches have significant overlap, however. Sub-branches Physical geography can be divided into several branches or related fields, as follows: * Geomorphology is concerned with understanding the surface of the Earth and the processes by which it is shaped, both at the present as well as in the past. Geomorphology as a field has several sub-fields that deal with the specific landforms of various environments e.g. desert geomorphology and fluvi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stream Pool
A stream pool, in hydrology, is a stretch of a river or stream in which the water depth is above average and the water velocity is below average. Formation A stream pool may be bedded with sediment or armoured with gravel, and in some cases the pool formations may have been formed as basins in exposed bedrock formations. Plunge pools, or plunge basins, are stream pools formed by the action of waterfalls. Pools are often formed on the outside of a bend in a meandering river. Dynamics The depth and lack of water velocity often leads to stratification in stream pools, especially in warmer regions. In warm arid regions of the Western United States, surface waters were found to be 3-9 °C higher than those at the bottom Habitat This portion of a stream often provides a specialized aquatic ecosystem habitat for organisms that have difficulty feeding or navigating in swifter reaches of the stream or in seasonally warmer water. Such pools can be important for fish habitat, espe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid
Rapids are sections of a river where the river bed has a relatively steep gradient, causing an increase in water velocity and turbulence. Rapids are hydrological features between a ''run'' (a smoothly flowing part of a stream) and a ''cascade''. Rapids are characterized by the river becoming shallower with some rocks exposed above the flow surface. As flowing water splashes over and around the rocks, air bubbles become mixed in with it and portions of the surface acquire a white color, forming what is called "whitewater". Rapids occur where the bed material is highly resistant to the erosive power of the stream in comparison with the bed downstream of the rapids. Very young streams flowing across solid rock may be rapids for much of their length. Rapids cause water aeration of the stream or river, resulting in better water quality. Rapids are categorized in classes, generally running from I to VI. A Class 5 rapid may be categorized as Class 5.1-5.9. While Class I rapids are eas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meander
A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank ( cut bank) and deposits sediments on an inner, convex bank which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous course as the channel migrates back and forth across the axis of a floodplain. The zone within which a meandering stream periodically shifts its channel is known as a meander belt. It typically ranges from 15 to 18 times the width of the channel. Over time, meanders migrate downstream, sometimes in such a short time as to create civil engineering challenges for local municipalities attempting to maintain stable roads and bridges.Neuendorf, K.K.E., J.P. Mehl Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Charlton, R., 2007. ''Fundamentals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravesend
Gravesend is a town in northwest Kent, England, situated 21 miles (35 km) east-southeast of Charing Cross (central London) on the Bank (geography), south bank of the River Thames and opposite Tilbury in Essex. Located in the diocese of Rochester, it is the administrative centre of the Gravesham, Borough of Gravesham. Its geographical situation has given Gravesend strategic importance throughout the maritime history, maritime and History of communication, communications history of South East England. A Thames Gateway commuter town, it retains strong links with the River Thames, not least through the Port of London Authority Pilot Station and has witnessed rejuvenation since the advent of High Speed 1 rail services via Gravesend railway station. The station was recently refurbished and now has a new bridge. Toponymy Recorded as Gravesham in the Domesday Book of 1086 when it belonged to Odo, Earl of Kent and Roman Catholic Diocese of Bayeux, Bishop of Bayeux, the half-broth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thames Barge
A Thames sailing barge is a type of commercial sailing boat once common on the River Thames in London. The flat-bottomed barges with a shallow draught and leeboards, were perfectly adapted to the Thames Estuary, with its shallow waters and narrow tributary rivers. The larger barges were seaworthy vessels, and were the largest sailing vessel to be handled by just two men. The average size was about 120 tons and they carried of canvas sail in six working sails. The mainsail was loose-footed and set up with a sprit, and was brailed to the mast when not needed. It is sheeted to a horse, as is the foresail; they require no attention when tacking. The foresail is often held back by the mate to help the vessel come about more swiftly. The topsail was usually first sail on and last sail off, being fixed to the topmast by hoops. In the upper reaches of the rivers and constricted harbours it reached into the clear air, and when approaching a berth casting off the halliard would drop it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Board On Geographic Names
The United States Board on Geographic Names (BGN) is a federal body operating under the United States Secretary of the Interior. The purpose of the board is to establish and maintain uniform usage of geographic names throughout the federal government of the United States. History On January 8, 1890, Thomas Corwin Mendenhall, superintendent of the US Coast and Geodetic Survey Office, wrote to 10 noted geographers "to suggest the organization of a Board made up of representatives from the different Government services interested, to which may be referred any disputed question of geographical orthography." President Benjamin Harrison signed executive order 28 on September 4, 1890, establishing the ''Board on Geographical Names''. "To this Board shall be referred all unsettled questions concerning geographic names. The decisions of the Board are to be accepted y federal departmentsas the standard authority for such matters." The board was given authority to resolve all unsettled ques ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
