Coral Reef

Coral reefs are a submarine geomorphologic feature found worldwide in tropical waters that provide habitat for thousands of species and invaluable resources for humanity. They are commonly distributed between latitudes 30 °N and 30° S. Coral reefs build in water temperatures [Page 582]that range from ∼20 to ∼30 °C and exist in clear waters with little to no suspended sediment or dissolved organic materials. Coral reefs also tend to be located at the western edge of ocean basins. The coral organisms that build reef structures are individual invertebrates that live in symbiosis with algae organisms known as zooxanthellae. As these individual corals grow, they produce a calcium carbonate (CaCO3) shell. Empty coral shells are the primary building material from which coral reefs are formed.