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Coral Island
A coral island is a type of island formed from coral detritus and associated organic material. It occurs in tropical and sub-tropical areas, typically as part of a coral reef which has grown to cover a far larger area under the sea. The term low island can be used to distinguish such islands from high islands, which are formed through volcanic action. Low islands are formed as a result of sedimentation upon a coral reef or of the uplifting of such islands. Ecosystem Coral reefs are some of the oldest ecosystems on the planet, over geological time, they form massive reefs of limestone. The reef environment supports more plant and animal species than any other habitat. Coral reefs are vital for life in multiple aspects some of which include structure, ecology, and nutrient cycles which all support biodiversity in the reefs. Coral reefs build massive calcareous skeletons that serve as homes for animals such as fish hiding inside the crooks and crannies of the reef and barnacle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamonds Thudufushi Beach And Water Villas, May 2017 -08
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen). Small numbers of defects or impurities (about one per million of lattice atoms) can color a diamond blue (boron), yellow (nitrogen), brown (defects), green (radiation exposure), purple, pink, oran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plate Tectonics
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by Earth science, geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called ''tectonics''. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust (geology), crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault (geology), fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Islet
An islet ( ) is generally a small island. Definitions vary, and are not precise, but some suggest that an islet is a very small, often unnamed, island with little or no vegetation to support human habitation. It may be made of rock, sand and/or hard coral; may be permanent or tidal (i.e. surfaced reef or seamount); and may exist in the sea, lakes, rivers or any other sizeable bodies of water. Definition As suggested by its origin ''islette'', an Old French diminutive of "isle", use of the term implies small size, but little attention is given to drawing an upper limit on its applicability. The World Landforms website says, "An islet landform is generally considered to be a rock or small island that has little vegetation and cannot sustain human habitation", and further that size may vary from a few square feet to several square miles, with no specific rule pertaining to size. Other terms * Ait (/eɪt/, like eight) or eyot (/aɪ(ə)t, eɪt/), a small island. It is espe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Level
Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised geodetic datumthat is used, for example, as a chart datum in cartography and Navigation, marine navigation, or, in aviation, as the standard sea level at which atmospheric pressure is measured to Calibration, calibrate altitude and, consequently, aircraft flight levels. A common and relatively straightforward mean sea-level standard is instead a long-term average of tide gauge readings at a particular reference location. The term ''above sea level'' generally refers to the height above mean sea level (AMSL). The term APSL means above present sea level, comparing sea levels in the past with the level today. Earth's radius at sea level is 6,378.137 km (3,963.191 mi) at the equator. It is 6,356.752 km (3,94 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niue
Niue is a self-governing island country in free association with New Zealand. It is situated in the South Pacific Ocean and is part of Polynesia, and predominantly inhabited by Polynesians. One of the world's largest coral islands, Niue is commonly referred to as "The Rock", which comes from the traditional name "Rock of Polynesia". Niue's position is inside a triangle drawn between Tonga, Samoa, and the Cook Islands. It is northeast of New Zealand, and northeast of Tonga. Niue's land area is about and its population was 1,689 at the Census in 2022. The terrain of the island has two noticeable levels. The higher level is made up of a limestone cliff running along the coast, with a plateau in the centre of the island reaching approximately above sea level. The lower level is a coastal terrace approximately 0.5 km (0.3 miles) wide and about 25–27 metres (80–90 feet) high, which slopes down and meets the sea in small cliffs. A coral reef surrounds the island; the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nauru
Nauru, officially the Republic of Nauru, formerly known as Pleasant Island, is an island country and microstate in the South Pacific Ocean. It lies within the Micronesia subregion of Oceania, with its nearest neighbour being Banaba (part of Kiribati) about to the east. With an area of only , Nauru is the List of countries and dependencies by area, third-smallest country in the world, larger than only Vatican City and Monaco, making it the smallest republic and island nation, as well as the smallest member state of the Commonwealth of Nations by area. Demographics of Nauru, Its population of about 10,800 is the world's List of countries and dependencies by population, third-smallest (not including colonies or overseas territories). Nauru is a member of the United Nations, the Commonwealth of Nations, and the Organisation of African, Caribbean and Pacific States. Settled by Micronesians circa 1000 Common Era, BCE, Nauru was annexation, annexed and claimed as a colony by the G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Makatea
Makatea, or Mangaia-te-vai-tamae, is a raised coral atoll in the northwestern part of the Tuamotus, which is a part of the French overseas collectivity of French Polynesia. It is located southwest from Rangiroa to the west of the Palliser Islands, Palliser group, which also is in French Polynesia. Makatea is surrounded by spectacular cliffs, rising to a plateau above sea level. This island is long, with a maximum width of in the south. It is in area. Makatea is one of only four islands of the Tuamotus, Tuamotu Archipelago (along with filled atolls Nukutavake, Tikei, and Tepoto (North), Tepoto Nord) that do not take the form of a typical atoll. History Makatea is one of the only Paumotuan islands with Drinking water, potable water. Its native name derived from the drinking water being brought out of its dark caves by the local people. "Mā," pure, clear; used here to mean water, "Atea," light of day and "K" for euphony. The other name of the Island was Mangaia-te-vai-tamāe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banaba
BanabaThe correct spelling and etymology in Gilbertese should be ''Bwanaba'' but the Constitution of Kiribati writes Banaba. Because of the spelling in English or French, the name was very often written Paanapa or Paanopa, as it was in 1901 Act. (; formerly Ocean Island) is an island of Kiribati in the Pacific Ocean. A solitary raised coral island west of the Gilbert Island Chain, it is the westernmost point of Kiribati, lying east of Nauru, which is also its nearest neighbour. It has an area of , and the highest point on the island is also the highest point in Kiribati, at in height. Along with Nauru and Makatea (French Polynesia), it is one of the important elevated phosphate-rich islands of the Pacific. History According to ''Te Rii ni Banaba (The Backbone of Banaba)'' by Raobeia Ken Sigrah, Banaban oral history supports the claim that the people of the Te Aka clan, which originated in Melanesia, were the original inhabitants of Banaba, having arrived before the arri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonate
A carbonate is a salt of carbonic acid, (), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group . The term is also used as a verb, to describe carbonation: the process of raising the concentrations of carbonate and bicarbonate ions in water to produce carbonated water and other carbonated beverageseither by the addition of carbon dioxide gas under pressure or by dissolving carbonate or bicarbonate salts into the water. In geology and mineralogy, the term "carbonate" can refer both to carbonate minerals and carbonate rock (which is made of chiefly carbonate minerals), and both are dominated by the carbonate ion, . Carbonate minerals are extremely varied and ubiquitous in chemically precipitated sedimentary rock. The most common are calcite or calcium carbonate, , the chief constituent of limestone (as well as the main component of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accretion (geology)
In geology, accretion is a process by which material is added to a tectonic plate at a subduction zone, frequently on the edge of existing continental landmasses. The added material may be sediment, volcanic arcs, seamounts, oceanic crust or other igneous features. Description Accretion involves the addition of material to a tectonic plate via subduction, the process by which one plate is forced under the other when two plates collide. The plate which is being forced down, the subducted plate, is pushed against the upper, over-riding plate. Sediment on the ocean floor of the subducting plate is often scraped off as the plate descends. This accumulated material is called an accretionary wedge (or accretionary prism), which is pushed against and attaches to the upper plate. In addition to accumulated ocean sediments, volcanic island arcs or seamounts present on the subducting plate may be amalgamated onto existing continental crust on the upper plate, increasing the contine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lagoon
A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') and ''atoll lagoons''. They have also been identified as occurring on mixed-sand and gravel coastlines. There is an overlap between bodies of water classified as coastal lagoons and bodies of water classified as Estuary, estuaries. Lagoons are common coastal features around many parts of the world. Definition and terminology Lagoons are shallow, often elongated bodies of water separated from a larger body of water by a shallow or exposed shoal, reef, coral reef, or similar feature. Some authorities include fresh water bodies in the definition of "lagoon", while others explicitly restrict "lagoon" to bodies of water with some degree of salinity. The distinction between "lagoon" and "estuary" also varies between authorities. Richard A. Davis J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atoll
An atoll () is a ring-shaped island, including a coral rim that encircles a lagoon. There may be coral islands or cays on the rim. Atolls are located in warm tropical or subtropical parts of the oceans and seas where corals can develop. Most of the approximately 440 atolls in the world are in the Pacific Ocean. Two different, well-cited models, the subsidence model and the antecedent karst model, have been used to explain the development of atolls.Droxler, A.W. and Jorry, S.J., 2021. "The Origin of Modern Atolls: Challenging Darwin's Deeply Ingrained Theory". ''Annual Review of Marine Science'', 13, pp. 537–573. According to Charles Darwin's subsidence model, the formation of an atoll is explained by the sinking of a volcanic island around which a coral fringing reef has formed. Over geologic time, the volcanic island becomes extinct and eroded as it subsides completely beneath the surface of the ocean. As the volcanic island subsides, the coral fringing reef becomes a ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
