An atoll (/ ˈæt.ɒl, - ɔːl, - oʊl, əˈtɒl, - ˈtɔːl, - ˈtoʊl /) [1] is a ring-shaped island, including a coral rim that encircles a lagoon. There may be coral islands or cays on the rim. [2][3] Atolls are located in warm …

atoll, coral reef enclosing a lagoon. Atolls consist of ribbons of reef that may not always be circular but whose broad configuration is a closed shape up to dozens of kilometres across, enclosing a lagoon …

Mar 19, 2025 · An atoll is a ring of coral that originally grew completely around the shoreline of an island, and which continued to grow upward on top of itself as the island subsided or eroded away.

Oct 19, 2023 · An atoll is a ring-shaped coral reef, island, or series of islets. The atoll surrounds a body of water called a lagoon.

May 10, 2025 · An atoll stands as one of Earth’s most remarkable natural formations—a ring-shaped coral reef encircling a lagoon where once stood a volcanic island. These living geological wonders …

For reef scientists, atolls are broadly defined as large, ring-shaped coral reefs that surround a central lagoon.

An atoll is a coral reef grown around a submerged volcanic island. Its defining feature is the lagoon, a shallow body of water in the center, connected to the open ocean by channels through the …