Coral reef A fringing reef forms around an extinct volcanic island as the island and ocean floor subsides. As the subsidence continues, the fringing reef becomes a barrier reef and ultimately an atoll reef. Darwin predicted that underneath each lagoon would be a bedrock base, the remains of the original volcano. Subsequent research supported this hypothesis. Darwin's theory followed from his understanding that coral polyps thrive in the tropics where the water is agitated, but can only live within a limited depth range, starting just below low tide. Where the level of the underlying earth allows, the corals grow around the coast
Coral World Ocean Park Coral World Ocean Park Coral World is a marine park and tourist attraction located next to Coki Beach on the East End of St. Thomas, U.S. Virgin Islands. Since its opening in 1978, the park has featured a signature Underwater Observatory Tower. The tower descends 20 feet in the ocean to allow underwater viewing. Later additions to the park include an 80,0000 gallon circular Caribbean Reef Encounter tank, which houses local fish and other sea life, and an enclosure for South American sea lions. The park uses an open-water system to circulate ocean water through the exhibits. Other park animals