Early diagenetic processes are not only found at the sediment/water transition or in deposits near the sediment surface, but also in the deep sediment layers. For this reason, the original composition of the sediments can be strongly influenced during the hundreds to thousands of years following deposition. The most important biogeochemical/early diagenetic processes that can potentially take place depending on the sediment depth, as well as the particular effect on the composition of the solid phase, are shown in the figure below.