They don't. Volcanoes rise from the bottom of the sea, and much later, coral might start living around the circular volcano and create an atoll eventually.
An atoll is a ring-shaped coral reef that forms around a lagoon. Charles Darwin's theory of how atolls are formed as remnants of ocean volcanoes is generally considered fact.
Some islands accrete by the eruption of lava, either underwater or through volcanoes. In some areas, living coral will build atolls in shallow seas.
Becuase I hate you!
Atolls
They are areas of land that are higher than the water level. They can be "made" through various processes such as undersea volcanoes (such as Hawaii), erosion of a headland or through biological processes such as coral atolls.
There are high mountains, coral atolls, and it is located in Oceania.
Kiritimati or Christmas Island
No they did not yet
atolls
Volcanic islands, coral atolls
Tokelau consists of three coral atolls, Atafu, Nukunonu, and Fakaofo.
Also called atolls they usuallyb have coral reefs and tropical trees.