Here's a breakdown of the process:
1. Weathering: Existing rocks are broken down by physical and chemical processes into smaller fragments (clasts).
2. Erosion: The clasts are transported by wind, water, or ice to a new location.
3. Deposition: The transported clasts settle and accumulate in layers.
4. Compaction: The weight of overlying sediments compresses the deposited clasts, squeezing out water and air.
5. Cementation: Dissolved minerals precipitate between the clasts, acting as a glue to bind them together.
Characteristics of clastic sedimentary rocks:
* Made of fragments (clasts): The size and shape of the clasts can vary widely, influencing the rock's texture and name.
* Layered structure: The deposition of sediments in layers creates a distinct banding pattern.
* Porosity and permeability: Clastic rocks often have spaces between clasts, which can hold fluids.
* Examples: Sandstone, shale, conglomerate, and breccia.
Examples of clastic sedimentary rocks and their clast size:
* Sandstone: Composed of sand-sized clasts (0.0625-2 mm).
* Shale: Composed of clay-sized clasts (<0.0625 mm).
* Conglomerate: Composed of rounded clasts larger than 2 mm.
* Breccia: Composed of angular clasts larger than 2 mm.
Note: Clastic sedimentary rocks are distinct from chemical sedimentary rocks (like limestone and rock salt), which are formed from the precipitation of minerals from solution.
