Fanning Island in the Republic of Kiribati is an atoll. An atoll is a type of low, coral island found in tropical oceans and consisting of a coral-algal reef usually surrounding an interior body of water called a lagoon or peninsula. Atolls generally mark the locations of subsided (or sunken) extinct volcanic islands; the shape of the atoll is determined by the initial coastline of the original volcanic island, and is maintained so long as coral growth is faster than subsidence, and is not disturbed by other factors. Some atolls contain volcanic remnant islands at their centers. An atoll's low coral-sand islands form as a result of wave action breaking off pieces of coral at the reef escarpment and piling them up behind.
Formation
In the dynamic process of coral atoll formation corals settle and grow around an oceanic island, forming a fringing reef. In favorable conditions, the reef will expand, and the interior island will subside. Eventually the island completely subsides beneath the water, leaving a ring of growing coral with an open lagoon in its center. The process of atoll formation may take as long as 30 million years to occur. Darwin published an explanation for the creation of coral atolls in the South Pacific (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 oceanicvalcano. He reasoned that a fringing coral reef surrounding a volcanic island in the tropical sea will grow upwards as the island subsides (sinks), eventually becoming a barrier reef island (as typified by an island such as Bora Bora and others in the Society Islands). The fringing reef becomes a barrier reef for the reason that the outer part of the reef maintains itself near sea level through biotic growth, while the inner part of the reef falls behind, becoming a lagoon because conditions are less favorable for the corals and calcareous algae responsible for most reef growth. In time, subsidence carries the old volcano below the ocean surface, but the barrier reef remains. At this point, the island has become an atoll. Atolls are the product of the growth of tropical marine organisms, so these islands are only found in warm tropical waters. Volcanic islands located beyond the warm water temperature requirements of reef building (hermatypic) organisms become seamounts as they subside and are eroded away at the surface. An island that is located where the ocean water temperatures are just sufficiently warm for upward reef growth to keep pace with the rate of subsidence is said to be at the Darwin Point.
Islands more polar evolve towards seamounts or guyots; islands more equatorial evolve towards atolls. Kiribati (kir'ibas') , officially Republic of Kiribati (2005 est. pop. 103,000), 342 sq mi (886 sq km), consisting of 33 islands scattered across 2,400 mi (3,860 km) of the Pacific Ocean near the equator. It includes 8 of the 11 Line Islands, including Kiritimati (formerly Christmas Island), as well as the Gilbert and Phoenix groups and Banaba (formerly Ocean Island). Tarawa is the capital. The population is nearly all Micronesian, with about 30% concentrated on Tarawa. Languages spoken are English (official) and Gilbertese. Inhabitants are about half Roman Catholic and 45% Protestant. Fishing and the growing of taro and bananas form the basis of the mainly subsistence economy. Fish and copra became the chief exports after the mining of Banaba's once thick phosphate deposits ended in 1979. A member of the Commonwealth of Nations, the nation is a republic with a president, a cabinet, and a unicameral legislature. You will find Fanning Island to be a charming place to visit. However it is not so easy to get to. Only cruse ships and cargo ships can get you there. The people have a very primitive life style as they only have one generator used for the emergency radio. They have to have everything brought in by ship. They live off the things they grow, fish they catch, and the water they can catch and store during the rainy season. Most of their income comes from what craft items they can sell to the tourist. It is nice to give them some money (a dollar or two) if you have them pose for any pictures. When you visit please go to the primary school nearby. Take with you all the school supplies you can. Remember there is no power so paper, pencils, pens, and water colors will be the type of things to take.
To get credit take an altitude reading by the base of the large flagpole near the dock, the sign at the primary school, and the large monument past the swimming area to the right of the dock. Send me (do not post) the answer to this question: How much does the level change from the lowest to the highest point. NOW REQUIRED take a picture of your hand, foot, or whatever at one of the three locations and include it with your posting.
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