Seawater synthetic calcite dissolution

Figure 13. Empirical reaction order and log of the rate constant for synthetic calcite dissolution in seawater as a function of phosphate concentration based on the data presented in Figure 12...

A major problem encountered in comparing the rates of dissolution measured in the laboratory with rates measured in the water column was that the rates measured in the laboratory were 10 to 100 times faster. It has subsequently been shown (30) that the difference in rates for the biogenic calcite can be largely attributed to the fact that Berger (42) used only large foramin-ifera, while Morse and Berner (45) used a total carbonate sediment sample. The reason for the difference in rates for the Iceland spar and synthetic calcites is less certain. One possibility is that surfaces exposed in seawater experience biofouling. 

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