Coal is a combustible rock that is classified as a fossil fuel.
Combustible rock
Coal is a combustible rock that is classified as a fossil fuel.
Coal is a nonrenewable fossil fuel that is combusted and used to generate electricity.
Fossil fuels are formed from the remains of ancient organisms.
Coal Mining Methods
The method used to mine coal depends on the terrain and the depth of the coal. Before the early 1970s most coal was taken from underground mines. Since then, coal production has shifted to surface mines.
Underground mining is required when the coal lies more than 200 feet (61 m) below ground. The depth of most underground mines is less than 1,000 feet (305 m), but a few are 2,000 feet (610 m) deep. In underground mines, some coal must be left untouched to form pillars that prevent the mines from caving in.
Three types of underground mines:
Surface mines are usually less than 200 feet (61 m) deep and can be developed in flat or hilly terrain.
Largest Coal Mining companies by Market Cap
Largest Coal Mining companies by Market Cap
Coal Mining Methods
The method used to mine coal depends on the terrain and the depth of the coal. Before the early 1970s most coal was taken from underground mines. Since then, coal production has shifted to surface mines.
Underground mining is required when the coal lies more than 200 feet (61 m) below ground. The depth of most underground mines is less than 1,000 feet (305 m), but a few are 2,000 feet (610 m) deep. In underground mines, some coal must be left untouched to form pillars that prevent the mines from caving in.
Three types of underground mines:
Surface mines are usually less than 200 feet (61 m) deep and can be developed in flat or hilly terrain.
Coal is a nonrenewable fossil fuel that is combusted and used to generate electricity.
Fossil fuels are formed from the remains of ancient organisms.
Combustible rock