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Braid Bar
Braid bars, or mid-channel bars, are river landforms typically present in braided river channels. These formations have many names, including medial, longitudinal, crescentic, and transverse bars, as well as the more colloquial sandflat. Braid bars are distinguished from point bars due to their presence in the middle of a flow channel, rather than along a bank of the river channel. Formation Braid bars often originate from remnants of point bars or the growth of mid-channel unit bars in braided rivers. These features typically form in rivers with a high sediment load, within channels characterized by a large bed load and easily- eroded bank material. There are several mechanisms of formation. One explanation is that flow in the river may be redirected over a point bar, wherein the bar may be separated from the bank and thus become isolated within the channel. This forms a small ‘island’ of sediment, which can evolve into a braid bar. Alternatively, an obstacle s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River
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, spr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bankfull Discharge
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrology
Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is called a hydrologist. Hydrologists are scientists studying earth or environmental science, civil or environmental engineering, and physical geography. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management. Hydrology subdivides into surface water hydrology, groundwater hydrology (hydrogeology), and marine hydrology. Domains of hydrology include hydrometeorology, surface hydrology, hydrogeology, drainage-basin management, and water quality, where water plays the central role. Oceanography and meteorology are not included because water is only one of many important aspects within those field ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limnology
Limnology ( ; from Greek λίμνη, ''limne'', "lake" and λόγος, ''logos'', "knowledge") is the study of inland aquatic ecosystems. The study of limnology includes aspects of the biological, chemical, physical, and geological characteristics of fresh and saline, natural and man-made bodies of water. This includes the study of lakes, reservoirs, ponds, rivers, springs, streams, wetlands, and groundwater.Wetzel, R.G. 2001. Limnology: Lake and River Ecosystems, 3rd ed. Academic Press () Water systems are often categorized as either running (lotic) or standing (lentic). Limnology includes the study of the drainage basin, movement of water through the basin and biogeochemical changes that occur en route. A more recent sub-discipline of limnology, termed landscape limnology, studies, manages, and seeks to conserve these ecosystems using a landscape perspective, by explicitly examining connections between an aquatic ecosystem and its drainage basin. Recently, the need to u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomorphology
Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform and terrain history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphologists work within disciplines such as physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field. Overview Earth's surface is modified by a combination of surface processes that shape landscapes, and geologic processes that cause tectonic uplift and subsidence, and shape the coastal geography. Surface processe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentology
Sedimentology encompasses the study of modern sediments such as sand, silt, and clay, and the processes that result in their formation (erosion and weathering), transport, deposition and diagenesis. Sedimentologists apply their understanding of modern processes to interpret geologic history through observations of sedimentary rocks and sedimentary structures. Sedimentary rocks cover up to 75% of the Earth's surface, record much of the Earth's history, and harbor the fossil record. Sedimentology is closely linked to stratigraphy, the study of the physical and temporal relationships between rock layers or strata. The premise that the processes affecting the earth today are the same as in the past is the basis for determining how sedimentary features in the rock record were formed. By comparing similar features today to features in the rock record—for example, by comparing modern sand dunes to dunes preserved in ancient aeolian sandstones—geologists reconstruct past envir ... [...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 coarse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bar (river Morphology)
A bar in a river is an elevated region of sediment (such as sand or gravel) that has been deposited by the flow. Types of bars include mid-channel bars (also called braid bars and common in braided rivers), point bars (common in meandering rivers), and mouth bars (common in river deltas). The locations of bars are determined by the geometry of the river and the flow through it. Bars reflect sediment supply conditions, and can show where sediment supply rate is greater than the transport capacity. A mid-channel bar, is also often referred to as a braid bar because they are often found in braided river channels. Braided river channels are broad and shallow and found in areas where sediment is easily eroded like at a glacial outwash, or at a mountain front with high sediment loads. These types of river systems are associated with high slope, sediment supply, stream power, shear stress, and bed load transport rates. Braided rivers have complex and unpredictable channel patter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Saskatchewan River
The South Saskatchewan River is a major river in Canada that flows through the provinces of Alberta and Saskatchewan. For the first half of the 20th century, the South Saskatchewan would completely freeze over during winter, creating spectacular ice breaks and dangerous conditions in Saskatoon, Medicine Hat and elsewhere. At least one bridge in Saskatoon was destroyed by ice carried by the river. The construction of the Gardiner Dam in the 1960s, however, lessened the power of the river by diverting a substantial portion of the South Saskatchewan's natural flow into the Qu'Appelle River. By the 1980s many permanent sandbars had formed due to the lowering of the level of the river. From the headwaters of the Bow River, the South Saskatchewan flows for . At its mouth at Saskatchewan River Forks, it has an average discharge of and has a watershed of , 1,800 of which are in Montana in the United States and in Alberta and Saskatchewan. Course The river originates at the confluence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yamuna
The Yamuna ( Hindustani: ), also spelt Jumna, is the second-largest tributary river of the Ganges by discharge and the longest tributary in India. Originating from the Yamunotri Glacier at a height of about on the southwestern slopes of Bandarpunch peaks of the Lower Himalaya in Uttarakhand, it travels a total length of and has a drainage system of , 40.2% of the entire Ganges Basin. It merges with the Ganges at Triveni Sangam, Allahabad, which is a site of the Kumbh Mela, a Hindu festival held every 12 years. Like the Ganges, the Yamuna is highly venerated in Hinduism and worshipped as the goddess Yamuna. In Hinduism she is the daughter of the sun god, Surya, and the sister of Yama, the god of death, and so is also known as Yami. According to popular legends, bathing in its sacred waters frees one from the torments of death. It crosses several states: Haryana and Uttar Pradesh, passing by Uttarakhand and later Delhi, and meeting its tributaries on the way, inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraná River
The Paraná River ( es, Río Paraná, links=no , pt, Rio Paraná, gn, Ysyry Parana) is a river in south-central South America, running through Brazil, Paraguay, and Argentina for some ."Parana River". Encyclopædia Britannica. Encyclopædia Britannica Online. Encyclopædia Britannica Inc., 2012. Web. 26 May. 2012 . "Rio de la Plata". Encyclopædia Britannica. Encyclopædia Britannica Online. Encyclopædia Britannica Inc., 2012. Web. 26 May. 2012 Among South American rivers, it is second in length only to the Amazon River. It merges with the Paraguay River and then farther downstream with the Uruguay River to form the Río de la Plata and empties into the Atlantic Ocean. The first European to go up the Paraná River was the Venetian explorer Sebastian Cabot, in 1526, while working for Spain. A drought hit the river in 2021, causing a 77-year low. Etymology In eastern South America there is "an immense number of river names containing the element ''para-'' or ''parana-''", ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagavanirktok River
The Sagavanirktok River or Sag River ( Iñupiaq: ''Saġvaaniqtuuq'') is a stream in the North Slope Borough of the U.S. state of Alaska. It is about long and originates on the north slope of the Brooks Range, flowing north to the Beaufort Sea near Prudhoe Bay. The Trans-Alaska Pipeline System and Dalton Highway roughly parallel it from Atigun Pass to Deadhorse. A glaciation happened approximately at the same time as the Illinoian Stage of central North America at the Sagavanirktok River. See also *List of rivers of Alaska This is a List of rivers in Alaska, which are at least fifth-order according to the Strahler method of stream classification, and an incomplete list of otherwise-notable rivers and streams. Alaska has more than 12,000 rivers, and thousands more st ... References Rivers of North Slope Borough, Alaska Rivers of Alaska Brooks Range {{Alaska-river-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
