Table of Contents
Introduction of Sedimentary Rocks
Sedimentary rocks are consists of minerals and organic particles. These minerals accumulated to form sedimentary rock. These particles settles to form sedimentary rock. These mineral particles are known as sediments.
See the below image of sedimentary rocks.
When molten lava emits from volcanoes, it settles to form sedimentary rocks. Geological fragments are formed by weathering and erosion of existing rocks.
Sedimentary rocks are thin layers above the crust composed mainly of igneous and metamorphic rocks. Sedimentary rock is deposited in strata-like strata, forming structures known as beds. Sedimentary rocks are usually deposited in large structures called sedimentary pools. Sedimentary rocks have also been discovered on Mars.
Sedimentary rocks are also important natural resources such as coal, fossil fuels, drinking water and minerals. The study of sedimentary rock formation sequences is a major source of information for understanding Earth’s history.
The science that deals with the properties and origins of sedimentary rocks is called sedimentology. Sedimentology is part of both geology and physical geography and partly overlaps with other fields of earth science such as soil science, geomorphology, geochemistry, and structural geology.
Sedimentary Rocks Examples
- Limestone
- Sandstone
- Slate
- Conglomerate
- Chart
- Breccia
- Dolomite
- Silt stone
- Chalk
- Mud brick
- Mudstone
- Coquina
- Silica clastic
- Pebbles
- Iron ore
- Bauxite
How Are Sedimentary Rocks Formed
Sedimentary rocks are formed by collection and settlement of material on the surface of the earth within bodies of water.
These types of rocks can be formed in 4 ways as given below.
- Deposits of other weathered rocks.
- Sediment accumulation and compaction.
- Deposit of biological activity results.
- Precipitation from solution.
Clastic Sedimentary Rocks
Clastic sedimentary rocks indicates properties of a sedimentary rocks. Characteristics of Clastic sedimentary rocks are base on particle size, shape and grade.
Clastic sedimentary rocks are formed by compaction and cementation of clastics, which are composed of individual mineral grains or rock fragments. Because their mineralogy is so diverse, clastic rocks are usually classified by grain size rather than composition.
3 Types of Sedimentary Rocks
1. Organic Sedimentary Rock
This type of rock is composed primarily of coal and limestone, formed by the accumulation and deposition of dead plants and animals in rock formations.
2. Clastic Sedimentary Rock
This type of rock is formed when layers of rock are created by mechanical weathering of various types of rock.
I have shown the image of clastic sedimentary rock in figure 2.
3. Chemical Sedimentary Rock
This type of rock is formed when the minerals present in the rock undergo chemical reactions and cool over time as precipitates before turning back into rock.
Uses of Sedimentary Rocks
Limestone which is comes from sedimentary rocks are used to make cements. Sandstone and limestone are used in construction industry. Quartz is a type of sedimentary rock used to make glass. Gypsum also comes from sedimentary rocks which have lots of uses. Natural gas, oil, coal, uranium, and other energy resources are formed in and originate from sedimentary rocks.