State the classification of sedimentary rocks.

Sedimentary rocks are classified into three main categories based on their origin: clastic, chemical, and organic sedimentary rocks.

1. Clastic sedimentary rocks are formed from the accumulation of fragments of pre-existing rocks and minerals. These fragments, called clasts, are transported and deposited by water, wind, ice, or gravity. Examples of clastic sedimentary rocks include sandstone, shale, and conglomerate.

2. Chemical sedimentary rocks are formed from the precipitation of minerals from water. These minerals are dissolved in water and then crystallize out of solution to form rock. Examples of chemical sedimentary rocks include limestone, dolomite, and rock salt.

3. Organic sedimentary rocks are formed from the accumulation of organic material, such as plant and animal remains. Over time, this organic material is compacted and cemented together to form rock. Examples of organic sedimentary rocks include coal, oil shale, and some types of limestone.

Classification of Sedimentary Rocks

- Clastic Sedimentary Rocks
- Formed from fragments (clasts) of pre-existing rocks
- Classified based on clast size:
- Conglomerate (coarse gravel)
- Breccia (angular fragments)
- Sandstone (sand-sized grains)
- Siltstone (silt-sized grains)
- Shale (clay-sized grains)

- Chemical Sedimentary Rocks
- Formed from the precipitation of dissolved minerals from water
- Classifications:
- Limestone (primarily calcite)
- Dolomite (calcite and magnesium carbonate)
- Chert (microcrystalline quartz)
- Evaporites (formed from the evaporation of water)

- Biochemical Sedimentary Rocks
- Formed from the accumulation of organic remains
- Classifications:
- Coal (fossilized plant material)
- Oil shale (sedimentary rock containing organic matter)
- Phosphate (formed from the accumulation of animal bones and shells)

- Volcaniclastic Sedimentary Rocks
- Formed from the accumulation of volcanic ash and other volcanic materials
- Classifications:
- Tuff (consolidated volcanic ash)
- Breccia (volcanic fragments in a sedimentary matrix)
- Agglomerate (volcanic blocks in a sedimentary matrix)

- Residual Sedimentary Rocks
- Formed from the weathering and erosion of bedrock
- Classifications:
- Laterite (iron-rich sedimentary rock)
- Bauxite (aluminum-rich sedimentary rock)