In many areas of the Carribbean with suitable environmental conditions and a gently sloping shelf, four coralline ecologic zones may be identified: a deep, quiet-water Dendrogyra zone, an intermediate moderately agitated Acropora cervicornis zone, a shallower agitated Acropora palmata zone, and a shallow quiet lagoonal zone. Patch reefs grow and trap distinctive coralline debris in the A. cervicornis zone, and barrier reefs grow and trap distinctive coralline debris in the A. palmata zone.

At Bonaire, with a steeply sloping island shelf and increased water agitation, the same ecologic zones are found. However, the shallower ecologic zones are not everywhere present, and the extent to which they are absent is proportional to the increased agitation of the water. Patch reefs and barrier reefs are not found. Instead coralline detritus is deposited as beach ridges. On the windward side of the island these ridges are composed mainly of corals and coral fragments from the Dendrogyra zone, whereas the beach ridges on the leeward side of the island are composed almost exclusively of corals and coral fragments from the A. cervicornis zone. The detrital content and geometry of these beach ridges are similar to those of subaqueous patch reefs, except that they are larger and bette developed. Modern beach ridges are being built on lithified Pleistocene beach ridges, developing a pinnaclelike complex. Evaporite pans formed behind the beach ridges. Thus, a lagoon to coral mount to shelf sequence is formed that might, if preserved in the geologic column, be misinterpreted as a patch or pinnacle reef development.

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