HOME
*



picture info

Longshore Current
Longshore drift from longshore current is a geological process that consists of the transportation of sediments (clay, silt, pebbles, sand, shingle) along a coast parallel to the shoreline, which is dependent on the angle incoming wave direction. Oblique incoming wind squeezes water along the coast, and so generates a water current which moves parallel to the coast. Longshore drift is simply the sediment moved by the longshore current. This current and sediment movement occur within the surf zone. The process is also known as littoral drift. Beach sand is also moved on such oblique wind days, due to the swash and backwash of water on the beach. Breaking surf sends water up the beach (swash) at an oblique angle and gravity then drains the water straight downslope (backwash) perpendicular to the shoreline. Thus beach sand can move downbeach in a sawtooth fashion many tens of meters (yards) per day. This process is called "beach drift" but some workers regard it as simply part o ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Longshore I18n
Longshore may refer to: People * Ashley Longshore, American painter and entrepreneur * Dick Longshore (1926–1988), American Navy veteran and politician *Hannah Longshore (1819–1901), American physician * Lucretia Longshore Blankenburg (1845–1937), American suffragist and writer *Nate Longshore (born 1986), American Football player * William H. Longshore (1841–1909), Civil War Medal of Honor Recipient *Anna M. Longshore Potts (1829–1912), physician Other uses * Longshore Sailing School *Longshore drift *Longshoreman A stevedore (), also called a longshoreman, a docker or a dockworker, is a waterfront manual laborer who is involved in loading and unloading ships, trucks, trains or airplanes. After the shipping container revolution of the 1960s, the number o ...
{{disambig, surname ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sediment Deposition
Deposition is the geological process in which sediments, soil and rocks are added to a landform or landmass. Wind, ice, water, and gravity transport previously weathered surface material, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment. Deposition 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 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 has induced chemical processes (diagenesis) to deposit further calcium carbonate. Similarly, the formation of coal begins with the deposition of organic material, mainly from plants, in anaerobic conditions. Null-point hypothesis The null ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Banks Peninsula
Banks Peninsula is a peninsula of volcanic origin on the east coast of the South Island of New Zealand. It has an area of approximately and encompasses two large harbours and many smaller bays and coves. The South Island's largest city, Christchurch, is immediately north of the peninsula. Geology Banks Peninsula forms the most prominent volcanic feature of the South Island, similar to — but more than twice as large as — the older Dunedin volcano (Otago Peninsula and Harbour) to the southwest. Geologically, the peninsula comprises the eroded remnants of two large (Lyttelton formed first, then Akaroa), and the smaller Mt Herbert Volcanic Group. These formed due to intraplate volcanism between approximately eleven and eight million years ago (Miocene) on a continental crust. The peninsula formed as offshore islands, with the volcanoes reaching to about 1,500 m above sea level. Two dominant craters formed Lyttelton and Akaroa Harbours. The Canterbury ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Rakaia River
The Rakaia River is in the Canterbury Plains in New Zealand's South Island. The Rakaia River is one of the largest braided rivers in New Zealand. The Rakaia River has a mean flow of and a mean annual seven-day low flow of . In the 1850s, European settlers named it the ''Cholmondeley River'', but this name lapsed into disuse. Description It rises in the Southern Alps, travelling in a generally easterly or southeasterly direction before entering the Pacific Ocean south of Christchurch. It forms a hapua as it reaches the ocean. For much of its journey, the river is braided river, braided, running through a wide shingle bed. Close to Mount Hutt, however, it is briefly confined to a narrow canyon known as the Rakaia Gorge. The Rakaia River is bridged in two places. The busiest crossing is at the small town of Rakaia, from the river mouth, where State Highway 1 (New Zealand), State Highway 1 using Rakaia Bridge and the South Island Main Trunk Railway cross the river using sepa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Hapua
A hapua is a river-mouth lagoon on a mixed sand and gravel (MSG) beach, formed at the river-coast interface where a typically braided, although sometimes meandering, river interacts with a coastal environment that is significantly affected by longshore drift. The lagoons which form on the MSG coastlines are common on the east coast of the South Island of New Zealand and have long been referred to as by the Māori. This classification differentiates hapua from similar lagoons located on the New Zealand coast termed waituna. Hapua are often located on paraglacial coastal areas where there is a low level of coastal development and minimal population density. Hapua form as the river carves out an elongated coast-parallel area, blocked from the sea by a MSG barrier which constantly alters its shape and volume due to longshore drift. Longshore drift continually extends the barrier behind which the hapua forms by transporting sediment along the coast. Hapua are defined as a narrow shor ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Kaitorete Spit
Kaitorete Spit is a long finger of land which extends along the coast of Canterbury in the South Island of New Zealand. It runs west from Banks Peninsula for 25 kilometres, and separates the shallow Lake Ellesmere / Te Waihora from the Pacific Ocean. It is technically a continuous barrier beach, though at its western end it tapers to a point less than 100 metres in width which is occasionally breached at high tide. The spit is noted for its isolation and for its pebbly beaches. At its eastern end is the small settlement of Birdlings Flat, and west of its narrowest point is the settlement of Taumutu. Geography Kaitorete is low-lying but is not prone to flooding. A gravel road extends along half of its length from the small settlement of Birdlings Flat at its easternmost point. At this point, the northern shore of the spit is washed by a tidal lagoon, Kaituna Lagoon, which is essentially a short broad arm of Lake Ellesmere. It is also at its point that the spit is at its wid ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Lake Ellesmere
Lake Ellesmere / Te Waihora is a broad, shallow coastal lake or waituna, in the Canterbury region of the South Island of New Zealand. It is directly to the west of Banks Peninsula, separated from the Pacific Ocean by the long, narrow, sandy Kaitorete Spit, or more correctly Kaitorete Barrier. It lies partially in extreme southeastern Selwyn District and partially in the southwestern extension of the former Banks Peninsula District, which now (since 2006) is a ward in the city of Christchurch. The lake holds high historical and cultural significance to the indigenous Māori population and the traditional Māori name ''Te Waihora'', means ''spreading waters''. It has officially had a dual English/Māori name since at least 1938. Geography and hydrology Currently Lake Ellesmere / Te Waihora is a brackish bar-type waterbody, commonly called a lake or lagoon. It covers an area of , and is New Zealand's 5th largest lake (by area). Waituna and river mouth lagoons, or hapua, form ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Waimakariri River
The Waimakariri River is one of the largest rivers in Canterbury, on the eastern coast of New Zealand's South Island. It flows for in a generally southeastward direction from the Southern Alps across the Canterbury Plains to the Pacific Ocean. The river rises on the eastern flanks of the Southern Alps, eight kilometres southwest of Arthur's Pass. For much of its upper reaches, the river is braided, with wide shingle beds. As the river approaches the Canterbury Plains, it passes through a belt of mountains, and is forced into a narrow canyon (the Waimakariri Gorge), before reverting to its braided form for its passage across the plains. It enters the Pacific north of Christchurch, near the town of Kaiapoi. Instead of being unoccupied Crown land as are most New Zealand river beds, the bed of the Waimakariri River is vested in the Canterbury Regional Council (Environment Canterbury). Name The name ''Waimakariri'' comes from the Māori words ''wai'', meaning ''water'', and ''makari ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

New Brighton, New Zealand
New Brighton is a coastal suburb of Christchurch, New Zealand, east of the city centre. It is one of eastern Christchurch's main entertainment and tourist centres, with its architecturally unique pier and scenic coastline. The 2011 Christchurch earthquakes caused significant damage in the area. History Māori connections New Brighton is of cultural significance for the local iwi or tribe Ngāi Tahu who are the kaitiaki or guardians of this takiwa or area. Ngāi Tūāhuriri hapū, a sub-tribe of Ngāi Tahu, hold manawhenua status (territorial rights) in respect to this area. Te Tai o Mahaanui refers to the coast and surrounding land of which New Brighton is a part. Naming The naming of New Brighton was apparently done on the 'spur of the moment' by William Fee, an early settler of the area. When Guise Brittan, the Waste Lands Commissioner, visited the area in December 1860, he was recognised and Fee chalked 'New Brighton' on a wooden plank, supposedly in reference to his ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bays, ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Angle
In Euclidean geometry, an angle is the figure formed by two Ray (geometry), rays, called the ''Side (plane geometry), sides'' of the angle, sharing a common endpoint, called the ''vertex (geometry), vertex'' of the angle. Angles formed by two rays lie in the plane (geometry), plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves may also define an angle, which is the angle of the rays lying tangent to the respective curves at their point of intersection. ''Angle'' is also used to designate the measurement, measure of an angle or of a Rotation (mathematics), rotation. This measure is the ratio of the length of a arc (geometry), circular arc to its radius. In the case of a geometric angle, the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Ocean Current
An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences. Depth contours, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents are primarily horizontal water movements. An ocean current flows for great distances and together they create the global conveyor belt, which plays a dominant role in determining the climate of many of Earth’s regions. More specifically, ocean currents influence the temperature of the regions through which they travel. For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the Gulf Stream, which makes northwest Europe much more temperate for its high latitude compared to other areas at ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]