Lithification is the complex process by which loose sediment grains become compacted and transformed into solid rock[1]. This process may occur at the time of sediment deposition or later[1].
The main processes involved in lithification are compaction and cementation[1][2]. Compaction involves the squeezing of sediment grains into a smaller volume by packing them more closely together[2]. This can happen through desiccation (removal of water from the pore space) or pressure solution at the points where sediment grains come into contact with each other[2]. Cementation, on the other hand, is the process by which minerals or other substances fill the spaces between the sediment grains and bind them together, resulting in the formation of a solid rock matrix[1].
These processes of compaction and cementation contribute to the destruction of porosity in the sediment, leading to the formation of solid rock[3]. Over time, as sediment continues to undergo these processes, it gradually transforms into a cohesive rock mass[3].
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