Formations of coral reefs

Coral reefs can take a variety of forms, defined in following:

• Fringing reef – a reef that is directly attached to a shore or borders it with an intervening shallow channel or lagoon.
• Barrier reef – a reef separated from a mainland or island shore by a deep lagoon.
• Patch reef – an isolated, often circular reef, usually within a lagoon or embayment.
• Apron reef – a short reef resembling a fringing reef, but more sloped; extending out and downward from a point or peninsular shore.
• Bank reef – a linear or semi-circular in outline, larger than a patch reef.
• Ribbon reef – a long, narrow, somewhat winding reef, usually associated with an atoll lagoon.
• Table reef – an isolated reef, approaching an atoll type, but without a lagoon.
• Coral Atolls- rings of coral that grow on top of old, sunken volcanoes in the ocean. They begin as fringe reefs surrounding a volcanic island, then, as the volcano sinks, the reef continues to grow, and eventually only the reef remains.