Ailsa Craig, an ancient volcanic plug off the south-west coast of Scotland

A small Fijian island. Ailsa Craig ( Scottish Gaelic: Creag Ealasaid) is an Island in the outer Firth of Clyde, Scotland where granite was quarried to Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. Fiji (Matanitu ko Viti फ़िजी officially the Republic of the Fiji Islands (Matanitu Tu-Vaka-i-koya ko Viti फ़िजी द्वीप समूह गणराज्य

A small island in the Adriatic Sea

A small island in Lower Saranac Lake in the Adirondacks in the U. Lower Saranac Lake is one of three connected lakes part of the Saranac River, near the village of Saranac Lake in the Adirondacks in northern New The Adirondack Mountains are a Mountain range located in the northeastern part of New York, that runs through Clinton, Essex, Franklin S.

An island (IPA: /ˈaɪlənd/) or isle (/ˈaɪl/) is any piece of land that is completely surrounded by water in two dimensions, above high tide, and isolated from other significant landmasses. Very small islands such as emergent land features on atolls are called islets. An atoll (pronounced /ˈætʌl/ is an island of Coral that encircles a Lagoon partially or completely For human anatomy see Islets of Langerhans An islet is a small Island. A key or cay is another name for a small island or islet. An island in a river or lake may be called an eyot, /ˈaɪət/. An ait (or eyot) is a small Island found in the middle of a River or Lake. There are two main types of islands: continental islands and oceanic islands. There are also artificial islands. An artificial island is an Island that has been constructed by humans rather than formed by natural means A grouping of geographically and/or geologically related islands is called an archipelago. An archipelago (ɑrkəˈpɛləgoʊ is a chain or cluster of Islands The word archipelago literally means "chief Sea " from Italian

The word island comes from Old English ī(e)gland (literally, "watery land"). However, the spelling of the word was modified in the 15th century by association with the etymologically unrelated Old French loanword isle. Etymology is the study of the History of Words &mdash when they entered a language from what source and how their form and meaning have changed over time ^[1]

There is no standard of size which distinguishes islands from islets and continents. For human anatomy see Islets of Langerhans An islet is a small Island. A continent is one of several large Landmasses on Earth. They are generally identified by Convention rather than any strict criteria with seven regions

When defining islands as pieces of land that are completely surrounded by water, narrow bodies of water like rivers and canals are generally left out of consideration. "Riverine" redirects here For the use of that term in Maritime geography, see there Canals are artificial channels for water There are two types of canals water conveyance canals which are used for the conveyance and delivery of water and Waterways For instance, in France the Canal du Midi connects the Garonne river to the Mediterranean Sea, thereby completing a continuous water connection from the Atlantic Ocean to the Mediterranean Sea. The Canal du Midi or Canal des Deux Mers ( Occitan: Canal de las Doas Mars / Canal del Miègjorn) is a 240 km long canal in the south of France The Garonne (Garonne in Occitan, Catalan and Spanish: Garona; Garumna is a River in southwest France and northern So technically, the land mass that includes the Iberian Peninsula and the part of France that is south of the Garonne River and the Canal du Midi is completely surrounded by water. The Iberian Peninsula, or Iberia, is located in the extreme southwest of Europe, and includes modern day Spain, Portugal, Andorra For a completely natural example, the Orinoco River splits into two branches near Tamatama, in Amazonas state, Venezuela. ORiNOCO is the brand name that was used for a family of wireless networking solutions by Proxim (previously Lucent) The southern branch flows south and joins the Rio Negro, and then the Amazon. Thus, all of the Guianas (Guyana, Suriname, and French Guiana) and substantial parts of Brazil and Venezuela are surrounded by (river or ocean) water. These instances are not generally considered islands.

This also helps explain why Africa-Eurasia can be seen as one continuous landmass (and thus technically the biggest island): generally the Suez Canal is not seen as something that divides the land mass in two. The Suez Canal is a Canal in Egypt. Opened in 1869 it allows Water transportation between Europe and Asia without circumnavigation

On the other hand, an island may still be described as such despite the presence of a land bridge, e. g. , Singapore and its causeway or the various Dutch delta Islands, such as IJsselmonde. Singapore IJsselmonde is a river Island between the Nieuwe Maas, Noord and Oude Maas branches rivers of the Rhine-Meuse delta in the Dutch The retaining of the island description may therefore be to some degree simply due to historical reasons - though the land bridges are often of a different geological nature (for example sand instead of stone), and thus the islands remain islands in a more scientific sense as well.

Types

Continental islands

Angel Island in San Francisco Bay

Continental islands are bodies of land that lie on the continental shelf of a continent. Angel Island is an island in San Francisco Bay that offers spectacular views of the San Francisco skyline the Marin County Headlands and Mount The continental shelf is the extended perimeter of each Continent and associated Coastal plain, which is covered during interglacial periods such Examples include Greenland and Sable Island off North America; Barbados and Trinidad off South America; Great Britain, Ireland and Sicily off Europe; Sumatra and Java off Asia; and New Guinea, Tasmania and Kangaroo Island off Australia. Greenland (Kalaallit Nunaat meaning "Land of the Greenlanders" Grønland is a self-governing Danish Province located between the Sable Island (French île de Sable) is a small Canadian island situated 180 km southeast of mainland Nova Scotia Barbados ( Portuguese word for bearded-ones, bɑrˈbeɪdoʊz -dɒs situated just east of the Caribbean Sea, is an independent Island nation Trinidad ( Spanish: " Trinity " is the largest and most populous of the two major islands and South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a See also Kingdom of Great Britain Great Britain (Breatainn Mhòr Prydain Fawr Breten Veur Graet Breetain is the larger of the two main islands Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world Sicily ( Italian and Sicilian: Sicilia) is an autonomous region of Italy. Sumatra (also spelled Sumatera) is the sixth largest island in the world (approximately 470000 km² and is the largest island entirely in Indonesia (two Java (Jawa is an Island of Indonesia and the site of its Capital city Jakarta. New Guinea, located just north of Australia, is the world's second largest island, having become separated from the Australian mainland when the area now known Tasmania is an Australian island and state of the same name It is located south of the eastern side of the Continent, being separated from it by Bass Kangaroo Island is Australia 's third largest Island - after Tasmania and Melville Island. For a topic outline on this subject see List of basic Australia topics.

A special type of continental island is the microcontinental island, which results when a continent is rifted. In Geology, a rift is a place where the Earth 's crust and Lithosphere are being pulled apart and is an example of Extensional tectonics Examples are Madagascar off Africa; the Kerguelen Islands; and some of the Seychelles. Madagascar, or Republic of Madagascar (older name Malagasy Republic) is an Island nation in the Indian Ocean off the southeastern The Kerguelen Islands (in French: commonly Îles Kerguelen or Archipel de Kerguelen but officially Archipel des Kerguelen or Archipel Seychelles (seɪˈʃɛl or /seɪˈʃɛlz/ in English and seʃɛl in French) officially the Republic of Seychelles (République des Seychelles Creole

Another subtype is an island or bar formed by deposition of tiny rocks where a water current loses some of its carrying capacity. A shoal or sandbar (also called sandbank) is a somewhat Linear Landform within or extending into a body of Water, An example is barrier islands, which are accumulations of sand deposited by sea currents on the continental shelf. A shoal or sandbar (also called sandbank) is a somewhat Linear Landform within or extending into a body of Water, Sand is a naturally occurring Granular material composed of finely divided rock and Mineral particles Another example is islands in river deltas or in large rivers. A delta is a Landform where the mouth of a River flows into an Ocean, Sea, Estuary, Lake or another river While some are transitory and may disappear if the volume or speed of the current changes, others are stable and long-lived.

Oceanic islands

The islands of Hawai'i are volcanic islands. The Island of Hawaii, also called the Big Island or Hawaii Island, is a volcanic Island in the U

Wake Island is a volcanic island that has become an atoll. Wake Island (also known as Wake Atoll) is a Coral atoll having a Coastline of 12 miles (19 kilometers in the North Pacific Ocean An atoll (pronounced /ˈætʌl/ is an island of Coral that encircles a Lagoon partially or completely

Subterranean isle in Križna jama

Oceanic islands are ones that do not sit on continental shelves. Križna jama ( Križna Cave or Cave of the Cross) is a Cave located in Loška dolina, Slovenia. They are volcanic in origin. Plate tectonics and hotspots Divergent plate boundaries At the One type of oceanic island is found in a volcanic island arc. These islands arise from volcanoes where the subduction of one plate under another is occurring. In Geology, a subduction zone is an area on Earth where two tectonic plates meet and move towards one another with one sliding underneath the other Examples include the Mariana Islands, the Aleutian Islands and most of Tonga in the Pacific Ocean. The Mariana Islands (also the Marianas; up to the early 20th century sometimes called Ladrones Islands, from Spanish Islas de los Ladrones meaning The Aleutian Islands (possibly from Chukchi aliat, " Island " are a chain of more than 300 small volcanic islands forming a Volcanic The Kingdom of Tonga is an Archipelago in the south Pacific Ocean comprising 169 islands 36 of them inhabited stretching over a distance of about 800 kilometres (500 miles The Pacific Ocean is the largest of the Earth 's Oceanic divisions Some of the Lesser Antilles and the South Sandwich Islands are the only Atlantic Ocean examples. The Lesser Antilles, also known as the Caribbees, are part of the Antilles, which together with the Bahamas and Greater Antilles form the South Georgia and the South Sandwich Islands ( SGSSI) is a British overseas territory in the southern Atlantic Ocean.

Another type of oceanic island occurs where an oceanic rift reaches the surface. In Plate tectonics, a divergent boundary or divergent plate boundary (also known as a constructive boundary or an extensional boundary) is a There are two examples: Iceland, which is the world's largest volcanic island, and Jan Mayen — both are in the Atlantic. Iceland, officially the Republic of Iceland ( ( Ísland or Lýðveldið Ísland ( Jan Mayen Island is a 55 km (34 miles long (southwest-northeast and 373 km² (144  mi²) in area Arctic Volcanic island in the

A third type of oceanic island is formed over volcanic hotspots. In Geology, a hotspot is a location on the Earth's surface that has experienced active volcanism for a long period of time A hotspot is more or less stationary relative to the moving tectonic plate above it, so a chain of islands results as the plate drifts. Plate tectonics (from Greek τέκτων tektōn "builder" or "mason" describes the large scale motions of Earth 's Lithosphere Over long periods of time, this type of island is eventually eroded and "drowned" by isostatic adjustment, becoming a seamount. Isostasy (Greek isos = "equal" stásis = "standstill" is a term used in Geology to refer to the state of gravitational equilibrium between the A seamount is a Mountain rising from the Ocean Seafloor that does not reach to the water's surface ( Sea level) and thus is not an Island Plate movement across a hot-spot produces a line of islands oriented in the direction of the plate movement. An example is the Hawaiian Islands, from Hawaii to Kure, which then extends beneath the sea surface in a more northerly direction as the Emperor Seamounts. The Hawaiian Islands, once known as the Sandwich Islands, form an Archipelago of 19 Islands and Atolls numerous smaller The State of Hawaii ( or həˈwaɪʔiː Hawaiian: Mokuāina o Hawaii) is a state in the United States located on an Archipelago in the Kure Atoll or Ocean Island ( Hawaiian: Mokupāpapa) lies some beyond Midway Atoll in the Northwestern Hawaiian Islands at. The Hawaiian-Emperor seamount chain is composed of the Hawaiian Ridge, consisting of the islands of the Hawaiian chain northwest to Kure Atoll, and the Emperor Another chain with similar orientation is the Tuamotu Archipelago; its older, northerly trend is the Line Islands. The Tuamotus or the Tuamotu Archipelago ( French: Îles Tuamotu officially Archipel des Tuamotu) are a chain of atolls in French Polynesia The Line Islands, or Equatorial Islands, are a group of eleven Atolls and low coral islands in the central Pacific Ocean south of the Hawaiian The southernmost chain is the Austral Islands, with its northerly trending part the atolls in the nation of Tuvalu. The Austral Islands ( French: Îles Australes or Archipel des Australes) are the southernmost group of islands in French Polynesia, an Tuvalu, formerly known as the Ellice Islands, is a Polynesian Island nation located in the Pacific Ocean midway between Hawaii and Tristan da Cunha is an example of a hotspot volcano in the Atlantic Ocean. Tristan da Cunha (ˈtrɪstən də ˈkuːnə is a group of remote volcanic Islands in the south Atlantic Ocean, 2816 km (1750 miles from South Another hot spot in the Atlantic is the island of Surtsey, which was formed in 1963. Surtsey ( Icelandic: " Surtur's island" is a volcanic Island off the southern

An atoll is an island formed from a coral reef that has grown on an eroded and submerged volcanic island. Coral reefs are Aragonite structures produced by living organisms found in marine waters with little to no nutrients in the water The reef rises to the surface of the water and forms a new island. Atolls are typically ring-shaped with a central lagoon. A lagoon is a body of comparatively shallow salt or Brackish water separated from the deeper Sea by a shallow or exposed sandbank, coral Examples include the Maldives in the Indian Ocean and Line Islands in the Pacific. The Maldives ( or, or Maldive Islands) officially the Republic of Maldives, is an Island nation consisting of a group of atolls stretching The Indian Ocean is the third largest of the world's Oceanic divisions covering about 20% of the water on the Earth 's surface The Line Islands, or Equatorial Islands, are a group of eleven Atolls and low coral islands in the central Pacific Ocean south of the Hawaiian

See also

• Desert island
• High island
• Insularity
• Island biogeography
• Island country
• Islescape
• Islomania
• List of artificial islands
• List of divided islands
• List of fictional islands
• List of islands
• List of islands by area
• List of islands by name
• List of islands by highest point
• List of islands by population
• Phantom island
• Private island
• Reef
• Skerry
• Small Island Developing States
• Tidal island

References

External links

• Definition of island from United Nations Convention on the Law of the Sea
• Listing of islands from United Nations Island Directory. The United Nations Convention on the Law of the Sea ( UNCLOS) also called the Law of the Sea Convention or the Law of the Sea treaty is the international agreement that resulted The United Nations ( UN) is an International organization whose stated aims are to facilitate cooperation in International law, International security