1. Weathering and Erosion: This is the breakdown of existing rocks (igneous, metamorphic, or even other sedimentary rocks) into smaller fragments.
* Weathering: This can be physical (like freezing/thawing or abrasion) or chemical (like dissolution or oxidation).
* Erosion: Once broken down, the fragments are transported away from their original location by wind, water, or ice.
2. Transportation and Deposition: The eroded rock fragments are carried by agents like rivers, glaciers, or wind. As the energy of the transporting agent decreases, the fragments settle and accumulate in a new location, often in layers.
* Sorting: During transport, fragments are sorted by size and density. Larger, heavier particles settle first, while finer particles travel further.
* Rounding: The fragments become rounded as they collide with each other during transport.
3. Lithification: This is the process of turning loose sediments into solid rock.
* Compaction: The weight of overlying sediments compresses the layers, squeezing out water and air.
* Cementation: Dissolved minerals in groundwater precipitate between the sediment grains, acting like glue to bind them together. This is what turns loose sediment into a solid rock.
These three steps work together to create the diverse range of clastic rocks we see, from sandstones to mudstones to conglomerates.
