Deposition - Sediment is deposited when the energy of the transporting medium becomes too low to continue the transport process. In other words, if the velocity of the transporting medium becomes to low to transport sediment, the sediment will fall out and become deposited. The final sediment thus reflects the energy of the transporting medium. Diagenesis - Diagenesis is the process that turns sediment into rock. The first stage of the process is compaction.
Compaction occurs as the weight of the overlying material increases.
Compaction forces the grains closer together, reducing pore space and eliminating some of the contained water. Some of this water may carry mineral components in solution, and these constituents may later precipitate as new minerals in the pore spaces. This causes cementation, which will then start to bind the individual particles together. Further compaction and burial may cause recrystallization of the minerals to make the rock even harder. Other conditions present during diagenesis, such as the presence of absence of free oxygen may cause other alterations to the original sediment.