An atoll is formed first as a reef that fringes a volcanic island.
As the island sinks (after the volcanic activity has ceased and the crust has cooled, becoming denser), the reef continues to build upward, eventually ending up as a ring-shaped structure.
An island of coral that encircles a lagoon partly or completely.
An island consisting of a circular coral reef surrounding a lagoon
An atoll is an island formed by a ring-shaped coral reef encircling a lagoon. Atoll's are mostly found in tropical waters because they require coral reef building.
Small clusters of islands, generally they have little elevation above sea-level.
An example of an atoll is Bikini Atoll
bikini atoll
coral
mob
midway atoll is located in the northern pacific ocean
An Atoll is the name used to refer to a group of related coral islands.
Palmyra Atoll is a thousand miles south of Hawaii.
lagoon
atoll
bikini atoll
The atoll in the Pacific Ocean is home to a diverse array of marine life and coral reefs.
Atoll
a group of small coral islands in the shape of a ring that encloses a lagoon
the oppsite of atoll is planet
A lagoon boundary is an atoll.
bikini atoll
Allot and atoll.
Atoll is a noun.
Let's not strand ourselves on this atoll.
Ailinglaplap Atoll's population is 1,959.
Aur Atoll's population is 438.