An atoll is a type of low, coral island found in tropical oceans and consisting of a coral-algal reef surrounding a central depression. The depression may be part of the emergent island, but more typically is a part of the sea (that is, a lagoon), or very rarely is an enclosed body of fresh, brackish, or highly saline water. Atoll - Usage. The word atoll comes from the Dhivehi (Indo-Aryan language of the Maldive Islands) word atholhu (Dhivehi: އަތޮޅު). Its first recorded use in English w ...

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• Atoll - Usage
• Atoll - Formation
• Atoll - Distribution and size
• Atoll - See Also

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Charles Darwin published an explanation for the creation of coral atolls in the South Pacific (Darwin, 1842) based upon observations made during a five-year voyage aboard the HMS Beagle (1831-1836). His explanation, which is accepted as basically correct, involved considering that several tropical island types—from high volcanic island, through barrier reef island, to atoll—represented a sequence of gradual subsidence of what started as an oceanic volcano. He reasoned that a fringing coral reef surrounding a volcanic island in the ...

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Atoll, Atoll - Usage, Atoll - Formation, Atoll - Distribution and size

Read more here: » Atoll: Encyclopedia II - Atoll - Formation

The distribution of atolls around the globe is instructive: most of the world's atolls are in the Pacific Ocean (with concentrations in the Tuamotu Islands, Caroline Islands, Marshall Islands, Coral Sea Islands, and the island groups of Kiribati and Tuvalu) and Indian Ocean (the Maldives, the Laccadive Islands, the Chagos Archipelago and the Outer Islands of the Seychelles). The Atlantic Ocean ocean has no large groups of atolls, other than eight atolls east of Nicaragua that belong to the Colo ...

See also:

Atoll, Atoll - Usage, Atoll - Formation, Atoll - Distribution and size

Read more here: » Atoll: Encyclopedia II - Atoll - Distribution and size