|
Deposition (sediment)
Deposition is the geological process in which sediments, soil and rock (geology), rocks are added to a landform or landmass. Wind, ice, water, and gravity Transportation (sediment), transport previously Weathering, weathered surface material, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment. This occurs when the forces responsible for sediment transportation are no longer sufficient to overcome the forces of gravity and friction, creating a resistance to motion; this is known as the null-point hypothesis. Deposition can also refer to the buildup of sediment from Organic matter, organically derived matter or chemical processes. For example, chalk is made up partly of the microscopic calcium carbonate skeletons of marine plankton, the deposition of which induced chemical processes (diagenesis) to deposit further calcium carbonate. Similarly, the formation of coal begins with the deposition of organic material, mainly from plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deposition Erosion
Deposition may refer to: * Deposition (law), taking testimony outside of court * List of deposed politicians, Deposition (politics), the removal of a person of authority from political power * Deposition (university), a widespread initiation ritual for new students practiced from the Middle Ages until the 18th century Art * Deposition from the Cross, the depiction of the removal of Jesus from the cross * Deposition (Bellini), ''Deposition'' (Bellini), a 1515–16 painting by Giovanni Bellini and his workshop * Deposition of Christ (Bronzino), ''Deposition of Christ'' (Bronzino), a 1545 oil painting * The Deposition (Michelangelo), ''The Deposition'' (Michelangelo), a 1547–55 marble sculpture * The Deposition from the Cross (Pontormo), ''The Deposition from the Cross'' (Pontormo), a 1528 oil painting * Deposition from the Cross, Volterra (Rosso Fiorentino), ''Deposition from the Cross'', Volterra (Rosso Fiorentino) * The Deposition (Raphael), ''The Deposition'' (Raphael), a 1507 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is a type of fossil fuel, formed when dead plant matter decays into peat which is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian (geology), Pennsylvanian) and Permian times. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its Electricity generation, electricity. Some iron and steel-maki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stokes Law
In fluid dynamics, Stokes' law gives the frictional force – also called drag force – exerted on spherical objects moving at very small Reynolds numbers in a viscous fluid. It was derived by George Gabriel Stokes in 1851 by solving the Stokes flow limit for small Reynolds numbers of the Navier–Stokes equations.Batchelor (1967), p. 233. Statement of the law The force of viscosity on a small sphere moving through a viscous fluid is given by: :_ = - 6 \pi \mu R where (in SI units): * _ is the frictional force – known as Stokes' drag – acting on the interface between the fluid and the particle (newtons, kg m s−2); * (some authors use the symbol ) is the dynamic viscosity ( Pascal-seconds, kg m−1 s−1); * is the radius of the spherical object (meters); * is the flow velocity relative to the object (meters per second). Note the minus sign in the equation, the drag force points in the opposite direction to the relative velocity: drag opposes the motion. Stokes' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reynolds Number
In fluid dynamics, the Reynolds number () is a dimensionless quantity that helps predict fluid flow patterns in different situations by measuring the ratio between Inertia, inertial and viscous forces. At low Reynolds numbers, flows tend to be dominated by laminar flow, laminar (sheet-like) flow, while at high Reynolds numbers, flows tend to be turbulence, turbulent. The turbulence results from differences in the fluid's speed and direction, which may sometimes intersect or even move counter to the overall direction of the flow (Eddy (fluid dynamics), eddy currents). These eddy currents begin to churn the flow, using up energy in the process, which for liquids increases the chances of cavitation. The Reynolds number has wide applications, ranging from liquid flow in a pipe to the passage of air over an aircraft wing. It is used to predict the transition from laminar–turbulent transition, laminar to turbulent flow and is used in the scaling of similar but different-sized fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Gravity
The gravity of Earth, denoted by , is the net acceleration that is imparted to objects due to the combined effect of gravitation (from mass distribution within Earth) and the centrifugal force (from the Earth's rotation). It is a vector quantity, whose direction coincides with a plumb bob and strength or magnitude is given by the norm g=\, \mathit\, . In SI units, this acceleration is expressed in metres per second squared (in symbols, m/ s2 or m·s−2) or equivalently in newtons per kilogram (N/kg or N·kg−1). Near Earth's surface, the acceleration due to gravity, accurate to 2 significant figures, is . This means that, ignoring the effects of air resistance, the speed of an object falling freely will increase by about every second. The precise strength of Earth's gravity varies with location. The agreed-upon value for is by definition. This quantity is denoted variously as , (though this sometimes means the normal gravity at the equator, ), , or simply ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphere
A sphere (from Ancient Greek, Greek , ) is a surface (mathematics), surface analogous to the circle, a curve. In solid geometry, a sphere is the Locus (mathematics), set of points that are all at the same distance from a given point in three-dimensional space.. That given point is the center (geometry), ''center'' of the sphere, and the distance is the sphere's ''radius''. The earliest known mentions of spheres appear in the work of the Greek mathematics, ancient Greek mathematicians. The sphere is a fundamental surface in many fields of mathematics. Spheres and nearly-spherical shapes also appear in nature and industry. Bubble (physics), Bubbles such as soap bubbles take a spherical shape in equilibrium. The Earth is spherical Earth, often approximated as a sphere in geography, and the celestial sphere is an important concept in astronomy. Manufactured items including pressure vessels and most curved mirrors and lenses are based on spheres. Spheres rolling, roll smoothly in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bed Load
The term bed load or bedload describes particles in a flowing fluid (usually water) that are transported along the stream bed. Bed load is complementary to suspended load and wash load. Bed load moves by rolling, sliding, and/or Saltation (geology), saltating (hopping). Generally, bed load downstream will be smaller and more rounded than bed load upstream (a process known as downstream fining). This is due in part to Wear, attrition and Abrasion (geology), abrasion which results from the stones colliding with each other and against the river channel, thus removing the rough texture (Rounding (sediment), rounding) and reducing the size of the particles. However, selective transport of sediments also plays a role in relation to downstream fining: smaller-than average particles are more easily Entrainment (physical geography), entrained than larger-than average particles, since the shear stress required to entrain a grain is linearly proportional to the diameter of the grain. Howev ... [...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] |
Bohai Bay
Bohai Bay () is one of the three major bays of the Bohai Sea, the northwestern and innermost gulf of the Yellow Sea. It is bounded by the coastlines of eastern Hebei province ( Tangshan and Cangzhou), Tianjin municipality and northern Shandong province ( Binzhou and Dongying) south of the Daqing River estuary (which is an old mouth of Luan River in Laoting County) and north of the Yellow River estuary. It is the most southerly water in the northern hemisphere where sea ice can form. The Bohai Bay is the drainage destination of the Hai River and 15 other rivers. Due to these rivers' muddy runoff, the bay used to be a highly silty water body, but extensive damming of the various river systems has greatly diminished siltage. Nevertheless, the Bohai Bay in effect concentrates the runoff of the whole eastern North China Plain, and the Bay is an intensely polluted body of water. Reduced silt deposition and sea level rise are causing problems with sea encroachment in some c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Wash
The Wash is a shallow natural rectangular bay and multiple estuary on the east coast of England in the United Kingdom. It is an inlet of the North Sea and is the largest multiple estuary system in the UK, as well as being the largest natural bay in England and is the outflow for the rivers River Witham, Witham, River Welland, Welland, River Nene, Nene and the River Great Ouse, Great Ouse. It is also one of the most important places of conservation in Europe, with several nature reserves located within this area. The coastline is partly in Lincolnshire and partly in Norfolk, England, Norfolk. The Lincolnshire side forms part of the only coastline of the East Midlands region whilst the Norfolk side forms the north-west corner of the East Anglia, East Anglian region. The coastline stretches from Gibraltar Point, Lincolnshire, Gibraltar Point just south of the seaside town of Skegness to Gore Point near the village of Holme-next-the-Sea, just east of the seaside town of Hunstanton i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akaroa Harbour
Akaroa Harbour is part of Banks Peninsula in the Canterbury region of New Zealand. The harbour enters from the southern coast of the peninsula, heading in a predominantly northerly direction. It is one of two major inlets in Banks Peninsula, on the coast of Canterbury, New Zealand; the other is Lyttelton Harbour on the northern coast. The name Akaroa is an alternative spelling of Whakaroa, Whangaroa or Wangaloa from the Kāi Tahu dialect of Māori. Whakaroa means "Long Harbour". The harbour was used commercially in the mid-19th century for ship-based and shore-based whaling. Cruise ships occasionally enter the harbour, with the passengers visiting Akaroa. Ōnawe Peninsula is at the head of the harbour, the former site of a Māori pā. Settlements Akaroa Harbour's waterfront has been continually inhabited since the 1840s. Ōnuku, Akaroa, Takapūneke, Takamatua, Robinsons Bay, Duvauchelle, Barrys Bay, French Farm, Tikao Bay and Wainui lie on the shoreline of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akaroa
Akaroa is a small town on Banks Peninsula in the Canterbury Region of the South Island of New Zealand, situated within a harbour of the same name. The name Akaroa is Ngāi Tahu, Kāi Tahu Māori language, Māori for "Long Harbour", which would be spelled in standard Māori. The area was also named ''Port Louis-Philippe'' by French colonial empire#Second French colonial empire (post-1830), French settlers after the reigning King of the French, French king Louis Philippe I. The town is by road from Christchurch and is the terminus of State Highway 75 (New Zealand), State Highway 75. It is set on a sheltered harbour and is overlooked and surrounded by the remnants of an eruptive centre of the miocene Banks Peninsula Volcano. History In 1830, the Māori settlement at Takapūneke, east of the current town of Akaroa, was the scene of a notorious incident. There were an estimated 400 Kāi Tahu in the pā and most were killed, with only the strongest taken as slaves. The captain of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
