Types Of Coral Reefs
Fringing Reef:
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A fringing reef is a coralline platform lying close to the shore extending outwards from the mainland.
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It is sometimes separated from the shore by a shallow lagoon.
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It is widest when fringing a protruding headland but completely absent when facing the mouth of a stream. The outer edge grows rapidly because of the splashing waves that continuously renew the supply of fresh food. The reefs may be about a mile wide, lying just above the level of low water and sloping steeply downwards on the seaward side to a depth of about 100 feet.
Barrier Reef:
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A barrier reef parallels to the coastline and is separated from the coast by a much wider and deeper channel or lagoon. The reef is partially submerged. Where it lies above the water level and sand can accumulate on it, a little vegetation is possible.
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The barrier reefs have narrow gaps at several places to allow the water from the enclosed lagoon to return to the open ocean. Such gaps are very useful for shipping and provide the only entrances for ships to enter or leave the lagoon.
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Atolls:
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Atolls are similar to barrier reefs except that they are circular in shape, enclosing a shallow lagoon without any land in the center. The encircling ring is usually broken in a few places to allow the free flow of water.
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On the inside of the reefs, sand and limestone debris collect and palm trees like coconuts may grow. Such palm trees thrive well in the brackish water of the lagoon.
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Patch Reefs:
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These are small, isolated reefs that grow up from the open bottom of the island platform or continental shelf.
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They usually occur between fringing reefs and barrier reefs
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They vary greatly in size, and they rarely reach the surface of the water.