Definition - What does Clastic mean?
Clastic is a type of sedimentary rock composed of clasts or fragments of preexisting minerals and sedimentary rocks. Clast is considered to be the fragments of geological detritus, smaller chunks of broken rocks which occurred because of the process of weathering and erosion. Geologists classify Clastic rocks based on their compositions and predominant grain sizes.
Petropedia explains Clastic
The most of the Earth’s surface (approximately 75%) is covered by various types of sedimentary rocks that contain huge deposits of biological detritus, forms of coal and formation of hydrocarbons. Primarily there are four types of sedimentary rocks that exist. They are:
- Clastic Rocks – These rocks are formed from the preexisting sedimentary rocks which were converted into small fragments or clasts due to the process of erosion and weathering. These rocks are rich in silica and are used to study the composition of the rock bed as they are small in size and can be easily carried. They exhibit same properties of hydrocarbons existence.
- Carbonate Rocks – These rocks are formed by organic and inorganic processes over a long period of time and composed of carbonate minerals in majority such as reef.
- Evaporites – These sedimentary rocks are formed because of evaporation of water from the earth’s surface. Common types of Evaporites include gypsum or halite.
- Chemical sedimentary rocks – These rocks are formed by the precipitation of minerals from acqueous solution and include some carbonates as well. These include chert and jaspilite.