There are no conclusive theories about the formation of these coral atolls. The most accepted theory is given by the English Evolutionist Sir Charles Darwin. He concluded in 1842 that the subsidence of a volcanic island resulted in the formation of a fringing reef and the continual subsidence allowed this to grow upwards.

When the volcanic island became completely submerged the atoll was formed encircling the lagoon where, with the action of the wind, waves, reef to currents and temperature, the coral islands were formed.