Decay of skeletal organic matrices and early diagenesis in coral skeletons

Abstract : Due to its particular mode of growth, the coral skeleton provides a natural model for evaluating the successive stages of diagenesis in a still-living organism. The spatial distribution of skeletal organic matrices and their early diagenesis have been investigated in a scleractinian skeleton with in situ micron-scale analyses by Raman Microspectroscopy. Results indicate that the decay of the organic matrices occurs within a few years. We suggest that the gradual deterioration of the skeletal organic matrices is a keymechanism driving earliest diagenesis in coral skeletons and represents the starting-point of the process of fossilization.