Availability and type of energy regulate the global distribution of neritic carbonates

The study of carbonate rocks is primarily reliant on microfacies analysis, which is strongly based on the comparison with modern allochem assemblages. Despite the existence of several models aimed at comprehensively explaining, on the bases of abiotic factors, the distribution of carbonate-producing organisms, a global, quantitative and standardized overview of the composition of shallow-water carbonate sediments is still missing. Aiming to address this gap in knowledge, the current study provides a global database of the available quantitative data on neritic carbonate sediments. This is paired with satellite-based observations for the abiotic parameters. The results highlight a non-linear, multi-variable, dependence in the distribution of allochems and suggest that depth, temperature, and trophic state are, to a certain extent, interchangeable. The implication of which is a level of non-uniqueness for paleoenvironmental interpretation. The resulting distribution is rather continuous and stretches along an energy gradient. A gradient extending from solar energy, with autotrophs and symbiont-bearing organisms to chemical energy with heterotrophs. Further, quantitative data from modern oceans are still required to disentangle the remaining elements of uncertainty.