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Atoll (Geoform)

Component: Geoform

Unique Identifier: 185

Geoform Origin Biogenic
Geoform Atoll
Geoform Type Submerged Atoll/Atoll Reef

Definition A ring-like coral reef that nearly (or entirely) encloses a reef lagoon. The volcanic island normally associated with an atoll may or may not be present. Atolls appear in plain view as a roughly circular reef that is surmounted by a chain of closely spaced, low, coral islets that encircle (or nearly encircle) a shallow lagoon in which there is no land or islands of non-coral origin; the reef is surrounded by open sea.