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Calcite cement in an ooid-rich limestone; Carmel Formation, Jurassic of Utah. Minerals bond grains of sediment together by growing around them. This process is called cementation and is a part of the rock cycle. Cementation involves ions carried in groundwater chemically precipitating to form new crystalline material between sedimentary grains ...
Whether the initial cementation was concentric or pervasive, there is considerable evidence that it occurred quickly and at shallow depth of burial. [45] [46] [47] [38] In many cases, there is clear evidence that the initial concretion formed around some kind of organic nucleus. [48] The origin of the carbonate-rich septaria is still debated.
In sedimentology, compaction is the process by which a sediment progressively loses its porosity due to the effects of pressure from loading. This forms part of the process of lithification . When a layer of sediment is originally deposited, it contains an open framework of particles with the pore space being usually filled with water.
Essentially, lithification is a process of porosity destruction through compaction and cementation. Lithification includes all the processes which convert unconsolidated sediments into sedimentary rocks.
In geotechnical engineering, soil compaction is the process in which stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water (or other liquid) being displaced from between the soil grains, then consolidation , not compaction, has ...
For example, in lithic sandstones, cementation is less extensive because pore space between framework grains is filled with a muddy matrix that leaves little space for precipitation to occur. This is often the case for mudrocks as well. As a result of compaction, the clayey sediments comprising mudrocks are relatively impermeable.
Portland cement is the most common type of cement and is a general purpose cement. The product is made with a combination of calcium, silicon, aluminum, iron, and other ingredients.
The particulate matter then undergoes compaction and cementation at moderate temperatures and pressures . [ 5 ] : 265–280 [ 15 ] : 147–154 Before being deposited, sediments are formed by weathering of earlier rocks by erosion in a source area and then transported to the place of deposition by water , wind , ice , mass movement or glaciers ...