Pseudo-atoll Pseudo-atoll A pseudo-atoll, like an atoll, is an island that encircles a lagoon, either partially or completely. A pseudo-atoll differs from an atoll as established by several authorities, such as how it is formed (not by subsidence, nor by coral). It is considered a preferable term to "near-atoll". There is a need for rigorous definition of "pseudo-atoll" before it can be accepted as a general term. Alexander Agassiz gave the term pseudo-atoll to "any ring-shaped reefs not formed as a result of subsidence". while Norman D. Newell and J. Keith Rigby called such reefs non-coral. and "We conclude that almost-atoll
Kolhumadulu Atoll Kolhumadulu Atoll Kolhumadulu Atoll (also known as Thaa Atoll) is an administrative division of the Maldives. It corresponds to the natural atoll of the same name. The ancient name of the island was Kolhumaduva during the time of King Koimala who united all atolls of the Maldives under one kingdom for the first time. Traditionally, Maldivians call this atoll simply Kolhumadulu, without adding the word "atholhu" at the end. Thaa is the code letters assigned to the atoll and is sometimes used by tourists to refer to the atoll itself. The waters surrounding this atoll are good fishing areas and