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Outer Islands (Seychelles)
The Outer Islands or Coralline Seychelles (archipelago) is a collective term for those islands of the Seychelles that are not on the shallow Seychelles Bank (Seychelles Plateau) which defines the location of the granitic Inner Islands archipelago to the east. The local Seychellois Creole name for the outer islands is ', while the French name is '. They are all of coral formation, and in the western Indian Ocean. History Until 2008, the islands were outside the administrative and electoral Districts of Seychelles. In 2008 the shrimp farm closed on Coëtivy Island which caused a wave of job-seekers coming to Mahé. The ministry of tourism was granted a free hand on these islands in order to settle down the unrest of the population, and declared it a district. It formed the Islands Development Company (IDC) to control the islands, and prepared a program called ''1 hotel 1 island''. Each island in the group should be leased to a hotel, which will in turn built several residential ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seychelles
Seychelles (, ; ), officially the Republic of Seychelles (french: link=no, République des Seychelles; Creole: ''La Repiblik Sesel''), is an archipelagic state consisting of 115 islands in the Indian Ocean. Its capital and largest city, Victoria, is east of mainland Africa. Nearby island countries and territories include the Comoros, Madagascar, Mauritius, and the French overseas departments of Mayotte and Réunion to the south; and Maldives and the Chagos Archipelago (administered by the United Kingdom as the British Indian Ocean Territory) to the east. It is the least populated sovereign African country, with an estimated 2020 population of 98,462. Seychelles was uninhabited prior to being encountered by Europeans in the 16th century. It faced competing French and British interests until coming under full British control in the late 18th century. Since proclaiming independence from the United Kingdom in 1976, it has developed from a largely agricultural society to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. A coral "group" is a colony of very many genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which, when m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amirante Islands
The Amirante Islands (''Les Amirantes'') are a group of coral islands and atolls that belong to the Outer Islands of the Seychelles. They stretch about 155 km from the African Banks (African Islands) in the north to Desnœufs (Isle des Noeufs) in the south, all on the shallow Amirantes Bank (Amirantes Plateau, with depths of mostly 25 to 70 m), except the main island Île Desroches in the east, and submerged Lady Denison-Pender Shoal at the northern end. 90 km south of the Amirante Islands is Alphonse Group, the closest group of islands, which are sometimes considered part of the Amirantes. History The Amirantes were discovered by Vasco da Gama on his second voyage of exploration in 1503, and later named "Ilhas do Almirante" (Admiral Islands). Previous knowledge of the islands by Arab and Indian traders is possible. The islands were claimed by Sieur Michel Blin for France in 1802. By the Treaty of Paris (1814), the islands were passed officially to the British, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ÃŽle Platte
Platte Island or Île Platte is an island in the Southern Coral Group that is part of the Outer Islands of the Seychelles. Geography The island is located south of the Seychelles Bank at . Coëtivy Island (also Southern Coral Group) lies further southeast. Platte Island is located south of Mahé, the main island of the Seychelles, and from their capital Victoria. The island, a low and wooded sand cay, ranges about from north to south, with a width from in the south to in the north and a land area of . Its height is 3 m above the sea level. History Platte was discovered and named in 1769 for its low topography by Lieutenant de Lampériaire of ''La Curieuse''. And it also known by its nickname ″ill Pllate″. In the 1840s there was sufficient guano on the island to make it worthwhile excavating, and it was still won in the 20th century. A visitor in 1905 stated that 1500 tons had been taken off the island the month before he arrived. He also reported on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Coral Group
Southern Coral Group is a collective term for two islands of Outer Islands of the Seychelles, lying in the south of the island nation, between 135 and 300 kilometers south of the capital, Victoria, on Mahé Island. Islands Two widely separated islands, with a distance of 171 km from one another, make up the Southern Coral Group. They are both sand cays, situated on the northeastern sides of pseudo-atolls: #Île Platte in the north #Coëtivy Island Coëtivy Island is a small coral island in the Seychelles south of Mahé, at . Along with Île Platte, the nearest neighbor northwest, it comprises the Southern Coral Group and therefore belongs to the Outer Islands. History It was named af ... in the southeast Population Both islands are inhabited. The main settlement is on Coëtivy Island. References External links Island guide 1Island guide 2National Bureau of StatisticsInfo on the island Outer Islands (Seychelles) Archipelagoes of Seychelles {{Seychell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Crust
Continental crust is the layer of igneous, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called ''sial'' because its bulk composition is richer in aluminium silicates (Al-Si) and has a lower density compared to the oceanic crust, called ''sima'' which is richer in magnesium silicate (Mg-Si) minerals. Changes in seismic wave velocities have shown that at a certain depth (the Conrad discontinuity), there is a reasonably sharp contrast between the more felsic upper continental crust and the lower continental crust, which is more mafic in character. The continental crust consists of various layers, with a bulk composition that is intermediate (SiO2 wt% = 60.6). The average density of continental crust is about , less dense than the ultramafic material that makes up the mantle, which has a density of around . Continental crust is also less dense ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is nearly alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granitic Seychelles
The Granitic Seychelles are the islands in Seychelles which lie in central position on the Seychelles Bank and are composed of granite rock. They make up the majority of the Inner Islands, which in addition include the coral islands along of the rim of the Seychelles Bank, namely Bird Island and Denis Island. The Granitic Seychelles contrast with the Coralline Seychelles or the Outer Islands, several island groups made up of low coral islands with dry, infertile soils. The Granitic Seychelles are home to tropical moist forests, with several endemic species, including the coco de mer (''Lodoicea maldivica''), and the jellyfish tree (''Medusagyne oppositifolia''). Geography Mahé is the largest and tallest island in Seychelles, at 145 square km and up to 905 m elevation. There are 42 granitic islands, in descending order of size: Mahé, Praslin, Silhouette, La Digue, Curieuse, Félicité, Frégate, Ste. Anne, North, Cerf, Marianne, Grand Sœur, Thérèse, Aride, Con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atoll
An atoll () is a ring-shaped island, including a coral rim that encircles a lagoon partially or completely. There may be coral islands or cays on the rim. Atolls are located in warm tropical or subtropical oceans and seas where corals can grow. Most of the approximately 440 atolls in the world are in the Pacific Ocean. Two different, well-cited models, the subsidence and antecedent karst models, 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 subsidence 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral Reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and jellyfish. Unlike sea anemones, corals secrete hard carbonate exoskeletons that support and protect the coral. Most reefs grow best in warm, shallow, clear, sunny and agitated water. Coral reefs first appeared 485 million years ago, at the dawn of the Early Ordovician, displacing the microbial and sponge reefs of the Cambrian. Sometimes called ''rainforests of the sea'', shallow coral reefs form some of Earth's most diverse ecosystems. They occupy less than 0.1% of the world's ocean area, about half the area of France, yet they provide a home for at least 25% of all marine species, including fish, mollusks, worms, crustaceans, echinoderms, sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D'Arros Island
D'Arros Island is part of the Amirante Islands group, which are in the Outer Islands (Coralline Seychelles) coral archipelago of the Seychelles islands and nation. The island is located west of the granitic Inner Seychelles archipelago, with a distance of 255 km south of Victoria, Seychelles. History The island was discovered in 1770 by European sailors. D'Arros Island bears the name of the Baron d'Arros, Marine Commandant of '' ÃŽle de France'' (now Mauritius), from 1770 to 1771. ;Private island In 1975, The island became the property of prince Shahram Pahlavi Nia of Iran. in 1998 it was bought by French billionaire Liliane Bettencourt (daughter of founder and main shareholder of L'Oreal) for US$18 million. ;Nature preserve In August 2012 it was revealed that the island had once more been sold, for US$60 million, to be managed by the Save Our Seas Foundation. In 2014, it was officially designated a nature reserve. Geography D'Arros Island is located only west of the no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Island Conservation Society
The Island Conservation Society (ICS) was registered as an NGO in Seychelles on 25 March 2001. The Head Office, known as The Island Conservation Centre, is situated at Pointe Larue, Mahé. ICS focusses on protection and rehabilitation of the small islands of Seychelles, particularly the outer islands. Most of the outer islands of Seychelles are Government owned and managed by the parastal company Islands Development Company (IDC). In 2007, ICS signed an agreement with IDC for conservation management on these islands. ICS now employs full-time scientists and rangers at conservation centres on four IDC islands, Silhouette Island, Alphonse Atoll, Desroches Island and Farquhar Atoll. ICS has also managed Aride Island Nature Reserve since October 2003. Aride was previously owned and managed by the Royal Society of Wildlife Trusts (RSWT) of UK. In October 2003, the reserve was leased to ICS and a series of conservation targets were set by RSWT. In 2006, upon satisfactory completion of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
