Encasement of Corals with Carbonate Minerals

Corals collected in July 2011 demonstrated extensive encrustation of corallites with carbonate minerals. The encrustation was most pronounced on samples collected on the reef-crest and on the fore-reef. Our hypotheses for this encrustation are based on the location of where the corals were found. We believe that corals found on the reef crest have precipitated calcium carbonate on the exoskeleton because of extreme turbulence and oxygenation along with drying during low tides. For corals at depth in the fore-reef, the non-coral created precipitation may arise from a high saturation index of aragonite in the water. This is possibly due to the extremely high amount of unconsolidated coral rubble present in response to the A. planci outbreak which destroyed the outer reef. Encrustation of montipora
This encasement can be seen at both the macroscopic and microscopic levels.
Encasement of non-coral generated calcium carbonate at the base of the Porites sample. encrusted porites
acanthastrea encrusted A corallite of Acanthastrea echinata encased in non-coral generated calcium carbonate. The retained fine structure of the corallite is evident despite the layer of encrusting calcium carbonate.