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Black Sea Undersea River
The Black Sea undersea river is a current of particularly saline water flowing through the Bosphorus Strait and along the seabed of the Black Sea. The discovery of the river, announced on 1 August 2010, was made by scientists at the University of Leeds, and is the first of its kind in the world. The undersea river stems from salty water spilling through the Bosphorus Strait from the Mediterranean Sea into the Black Sea, where the water has a lower salt content. The river system formed roughly 7,500 years ago when the Bosphorus developed its two-way depth-separated flow. Scientists have previously discovered channels running along ocean floors, based on sonar scanning. One of the largest of these runs from the mouth of the Amazon River into the Atlantic Ocean. Though it was suspected that these channels might function as rivers, it was only with the discovery of the Black Sea river that this suspicion was confirmed. Because of the power and unpredictability of these streams, they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autonomous Underwater Vehicle
An autonomous underwater vehicle (AUV) is a robot that travels underwater without requiring continuous input from an operator. AUVs constitute part of a larger group of undersea systems known as unmanned underwater vehicles, a classification that includes non-autonomous remotely operated underwater vehicles (ROVs) – controlled and powered from the surface by an operator/pilot via an umbilical or using remote control. In military applications an AUV is more often referred to as an unmanned undersea vehicle (UUV). Underwater gliders are a subclass of AUVs. Homing torpedoes can also be considered as a subclass of AUVs. History The first AUV was developed at the Applied Physics Laboratory at the University of Washington as early as 1957 by Stan Murphy, Bob Francois and later on, Terry Ewart. The "Self-Propelled Underwater Research Vehicle", or SPURV, was used to study diffusion, acoustic transmission, and submarine wakes. Other early AUVs were developed at the Massachus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Oceanography
Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters. Physical oceanography is one of several sub-domains into which oceanography is divided. Others include biological, chemical and geological oceanography. Physical oceanography may be subdivided into ''descriptive'' and ''dynamical'' physical oceanography. Descriptive physical oceanography seeks to research the ocean through observations and complex numerical models, which describe the fluid motions as precisely as possible. Dynamical physical oceanography focuses primarily upon the processes that govern the motion of fluids with emphasis upon theoretical research and numerical models. These are part of the large field of Geophysical Fluid Dynamics (GFD) that is shared together with meteorology. GFD is a sub field of Fluid dynamics describing flows occurring on spatial and temporal scales that are greatly influenced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subterranean River
A subterranean river (also known as an underground river) is a river or watercourse that runs wholly or partly beneath the ground, one where the riverbed does not represent the surface of the Earth. It is distinct from an aquifer, which may flow like a river but is contained within a permeable layer of rock or other unconsolidated materials. A river flowing below ground level in an open gorge is not classed as subterranean. Some natural rivers may be entirely subterranean, collecting in and flowing through cave systems. In karst topography, rivers that originate above ground can disappear into sinkholes, continuing underground until they reappear on the surface downstream, possibly having merged with other subterranean rivers. The longest subterranean river in the world is the Sistema Sac Actun cave system in Mexico. Subterranean rivers can also be the result of covering over a river or diverting its flow into culverts, usually as part of urban development.Richard J. Heggen: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kuma–Manych Depression
The Kuma–Manych depression () is a depression (geology), geological depression in southwestern Russia that separates the East European Plain, Russian Plain to the north from North Caucasus, Ciscaucasia to the south. It is named after the Kuma (Russia), Kuma and Manych rivers. Geography Kuma–Manych depression is sometimes regarded as a definition for the natural boundaries between the continents of Earth#Asia and Europe, boundary between Asia and Europe. The Rostov Nature Reserve is located within the depression. See also * Eurasia Canal * Manych Ship Canal * Terek–Kuma Lowland References Depressions of Russia Landforms of Europe Landforms of Kalmykia Landforms of Stavropol Krai {{South-Russia-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oneindia
Oneindia.com is an Indian news website established in January 2006 by BG Mahesh. The website provides news updates, information on sports, events, travel, entertainment, business, lifestyle, videos, and classifieds in seven different Indian languages and English. In June 2021, its Alexa ranking in India is 134. It is owned by Greynium Information Technologies Pvt Ltd. It is available in Kannada, Hindi, Telugu, Tamil, Bengali, Gujarati, and Malayalam Malayalam (; , ) is a Dravidian languages, Dravidian language spoken in the Indian state of Kerala and the union territories of Lakshadweep and Puducherry (union territory), Puducherry (Mahé district) by the Malayali people. It is one of .... History OneIndia rebranded in 2024 with the launch of its new logo. References External links * {{DEFAULTSORT:Oneindia.com Indian news websites Multilingual websites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to per mille, ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a state function, thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Current
In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force between objects and the Earth. This force is dominated by the combined gravitational interactions of particles but also includes effect of the Earth's rotation. Gravity gives weight to physical objects and is essential to understanding the mechanisms responsible for surface water waves and lunar tides. Gravity also has many important biological functions, helping to guide the growth of plants through the process of gravitropism and influencing the circulation of fluids in multicellular organisms. The gravitational attraction between primordial hydrogen and clumps of dark matter in the early universe caused the hydrogen gas to coalesce, eventually condensing and fusing to form stars. At larger scales this results in galaxies and cluste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapids
Rapids are sections of a river where the river bed has a relatively steep stream gradient, gradient, causing an increase in water velocity and turbulence. Flow, gradient, constriction, and obstacles are four factors that are needed for a rapid to be created. Physical factors Rapids are hydrology, hydrological features between a ''run'' (a smoothly flowing part of a stream) and a ''waterfall#Types, cascade''. Rapids are characterized by the river becoming shallower with some Rock (geology), 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 stream bed, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterfall
A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in several ways, but the most common method of formation is that a river courses over a top layer of resistant bedrock before falling onto softer rock, which erodes faster, leading to an increasingly high fall. Waterfalls have been studied for their impact on species living in and around them. Humans have had a distinct relationship with waterfalls since prehistory, travelling to see them, exploring and naming them. They can present formidable barriers to navigation along rivers. Waterfalls are religious sites in many cultures. Since the 18th century, they have received increased attention as tourist destinations, sources of hydropower, andparticularly since the mid-20th centuryas subjects of research. Definition and terminology A waterfal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floodplain
A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrology), discharge.Goudie, A. S., 2004, ''Encyclopedia of Geomorphology'', vol. 1. Routledge, New York. The soils usually consist of clays, silts, sands, and gravels deposited during floods. Because of regular flooding, floodplains frequently have high soil fertility since nutrients are deposited with the flood waters. This can encourage farming; some important agricultural regions, such as the Nile and Mississippi Basin, Mississippi Drainage basin, river basins, heavily exploit floodplains. Agricultural and urban regions have developed near or on floodplains to take advantage of the rich soil and freshwater. However, the Flood risk, risk of inundation has led to increasing efforts to Flood control, control flooding. Formation Most floodplai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
