Three types of Sedimentary Rocks

Three Types of Sedimentary Rocks

Sedimentary rocks are formed by the accumulation and cementation of sediment. The three main types of sedimentary rocks are:

Clastic Rocks: Clastic rocks are formed from the consolidation of sediment that has been transported and deposited by wind, water, or ice. The size and shape of the sediment particles determine the type of clastic rock that is formed. For example, conglomerate is a clastic rock that is composed of large, rounded pebbles or cobbles, while sandstone is composed of smaller, more angular sand grains.

clastic sedimentary rock

Chemical Rocks: Chemical rocks are formed when minerals precipitate out of a solution. This can occur when the solution is saturated with the mineral, or when the solution’s pH or temperature changes. Chemical rocks include limestone, which is composed of calcium carbonate, and dolomite, which is composed of calcium magnesium carbonate.

dolomite

Organic Rocks: Organic rocks are formed from the remains of plants and animals. These rocks can be either clastic or chemical in composition. For example, coal is a clastic organic rock that is composed of the compressed remains of plants, while limestone is a chemical organic rock that is composed of the calcium carbonate shells of marine animals.

coal