Atoll - Wikipedia
As the volcanic island subsides, the coral fringing reef becomes a barrier reef that is detached from the island. Eventually, reef and the small coral islets on top of it are all that is left of the original island, and a lagoon has taken the place of the former volcano. The lagoon is not the former volcanic crater.
Atoll | Definition & Facts | Britannica
Oct 17, 2024 — 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 that may be approximately 50 metres (160 feet) deep or more.
Atoll - Education | National Geographic Society
Oct 19, 2023 — An atoll is a ring-shaped coral reef, island, or series of islets. An atoll surrounds a body of water called a lagoon. Sometimes, atolls and lagoons protect a central island. Channels between islets connect a lagoon to the open ocean or sea. Atolls develop with underwater volcanoes, called seamounts. First, the volcano erupts, piling up lava on ...
How a coral atoll forms - NOAA's National Ocean Service
This animation shows the dynamic process of how a coral atoll forms. Corals (represented in tan and purple) begin to settle and grow around an oceanic island forming a fringing reef. It can take as long as 10,000 years for a fringing reef to form.
Atoll Facts and Information - Coral Reef Info
What is an “atoll”? For reef scientists, atolls are broadly defined as a large, ring-shaped coral reefs that surround a central lagoon. Coming up with a more specific and unambiguous definition of such reef formations is not all that easy however.
Birth of an Atoll - Smithsonian Ocean
An atoll is a ring-shaped coral reef that forms as an old volcano erodes. This video delves into how this process plays out over geologic time.
What Is An Atoll? - WorldAtlas
Apr 17, 2019 — An atoll is a type of coral reef with a coral rim that partially or completely surrounds a water body known as a lagoon. It is usually formed from a fringing reef around a volcanic island.
Atoll Reefs – Natures Marine Masterpieces - Green Living Answers
Uncover the captivating beauty of atoll reefs, the ring-shaped coral islands enclosing stunning lagoons teeming with vibrant marine life in tropical paradises.
What are the three main types of coral reefs? - NOAA's National …
Jun 16, 2024 — The three main types of coral reefs are fringing, barrier, and atoll. Schools of colorful pennantfish, pyramid, and milletseed butterflyfish live on an atoll reef in the Northwestern Hawaiian Islands.
Coastal And Oceanic Landforms: What Is An Atoll? - WorldAtlas
Apr 25, 2017 — An atoll is a ring-shaped coral reef or series of coral rims that encircle a lagoon either partially or wholly. Atoll and lagoons form a rim around an island that offers protection to the central island.