Sedimentary rocks are formed through a process called lithification. This involves the compaction and cementation of sedimentary particles that have been deposited and accumulated over time. The process of sedimentary rock formation can be broken down into several stages:

1. Weathering and erosion
- The first stage of sedimentary rock formation involves the breaking down of existing rocks into smaller particles through weathering and erosion.
- Weathering can occur through physical processes such as freezing and thawing, or through chemical processes such as acid rain.
- Erosion involves the transportation of these particles by water, wind, or ice, and their deposition in a new location.

2. Deposition
- The second stage involves the deposition of these particles in a new location, such as a riverbed, lake, or ocean floor.
- The size and shape of these particles will determine where they are deposited and how they will be sorted.

3. Compaction
- Over time, these deposited particles become buried under more layers of sediment, causing them to become compacted by the weight of the layers above.
- As the particles become more tightly packed, they lose their original shape and size, and the spaces between them become smaller.

4. Cementation
- The final stage of sedimentary rock formation involves the cementation of the particles into a solid rock.
- This occurs when minerals such as silica or calcium carbonate are deposited in the spaces between the particles, binding them together.
- The type of cementing mineral will determine the type of sedimentary rock that is formed.

In conclusion, sedimentary rocks are formed through the processes of weathering, erosion, deposition, compaction, and cementation. The type of sedimentary rock that is formed will depend on the size and shape of the deposited particles, as well as the type of cementing mineral that is present.

Sedimentary rock are formed by the river and the air. they collect the soil and the soil with the river which is in the shores of the river formed sedimentary soil.