Sedimentary rocks are formed by the lithification (cementing, compacting, and hardening) of existing rock or the bones, shells, and pieces of formerly living things. Rocks are weathered and eroded into tiny particles which are then transported and deposited along with other pieces of rock called sediments.
Sediments are cemented together and compacted and hardened over time by the weight and pressure of up to thousands of feet of additional sediments above them. Eventually, the sediments are lithified and become solid sedimentary rock. These sediments that come together are known as clastic sediments. Sediments usually sort themselves by the size of the particles during the deposition process so sedimentary rocks tend to contain similarly sized sedimentary particles.
An alternative to clastic sediments are chemical sediments which are minerals in solution that harden. The most common chemical sedimentary rock is limestone, which is a biochemical product of calcium carbonate created by the parts of dead creatures.
Approximately three-quarters of the earth's bedrock on the continents is sedimentary.
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Sediments are deposited, compacted, and cemented to form sedimentary rocks. First, sediments are laid down by water, wind, or ice. Over time, pressure and water squeeze out air and water between the sediments, causing them to compact. Minerals dissolved in water cement the sediment grains together to form solid rock.
The processes of compaction and cementation of this sediment over a long period of time turn the sediment into rock.
Sedimentary rock can be broken down into sediment through processes like weathering, erosion, and transportation. However, this process takes a very long time and is influenced by various factors such as temperature, pressure, and geological conditions. It is a natural cycle where sediment can be transformed into sedimentary rock and then back into sediment over millions of years.
it gets weathered into sediment, then it gets washed into the ocean, sediment layers up over millions of years, and it gets squashed into sedimentery rock, then metamorphic and so on.
The sediment transport by the rock cycle
The ease with which water flows through the open spaces in a rock or sediment indicates the permeability of the rock or sediment. Permeability refers to the ability of fluids to flow through the rock or sediment. A more permeable rock or sediment will have higher porosity and allow for better fluid flow.