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 …

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 …

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.

Nov 2, 2025 · An atoll is a ring-shaped coral reef structure that develops in warm, tropical oceanic waters, typically far from continental landmasses. This formation encircles a body of water, known as …

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.