Coal Formation And Distribution
Coal is a sedimentary, organic rock which is flammable. Coal is composed primarily of carbon along with other elements such as hydrogen, sulphur, oxygen, and nitrogen. Coal is mostly used for power generation and metallurgy. Coal reserves are widely distributed across the world. However, United States of America, Russia, China and India, combined together has more than 50 percent of the world's recoverable coal reserves.
Formation and Distribution of Coal
Coal is also the cheapest source of power if used near the coal mines. Since it is bulky, its transportation to far off places involves high costs. For this reason, the industries which consume a large quantity of coal, are located near coal mines. Coal is used as a source of power for running machines, trains, ships, etc. Coal is also essential for the manufacture of iron and steel and a variety of chemicals. Coal-tar and chemicals such as ammonia, benzol, etc. are obtained as by-products in the manufacture of iron and steel when coal is burnt to get the coke.
Formation of Coal
- Coal began to develop about 300 million years ago, during the Carboniferous period. During this time, the Earth was covered in wide, shallow seas and thick forests.
- First of all, the plant matter in wetlands such as ferns, shrubs, trees, and algae died and accumulated on the surface.
- This plant matter then got buried under the surface of the earth with no exposure to air.
- As the plant matter moved deeper under Earth s surface, it encountered increased temperatures and higher pressure.
- Anaerobic bacteria then decomposed this organic plant matter and, produced carbon dioxide and methane.
- This occurred for several thousands of years which formed several meters of partially decayed plant matter known as peat.
- These peat layers store massive amounts of carbon many meters underground. The peat formed, itself can be burned for fuel, and is a major source of heat energy in countries such as Scotland, Ireland, and Russia.
- When this peat is deeply buried, water and other compounds is squeezed out from the increasing pressure and the lowest quality of coal, lignite is formed.
- With increasing pressures and temperatures, lignite coal is transformed into higher quality "black coals".
- Lignite is transformed into sub-bituminous coal, then bituminous coal, and lastly anthracite.
Major varieties of Coal
- Anthracite- It is the best quality coal. It contains about 80 to 90 percent carbon. It is hard coal. In India, it is mainly found in the district of Reasi in the state of Jammu and Kashmir.
- Bituminous- It is the most widely available and used coal. It is of medium quality. It contains about 40 to 75 percent carbon. It is soft coal. In India, much of the coal comes under this category.
- Lignite- It is of low quality. It is brown in colour. It contains about 30 to 40 percent coal.
- Peat- It is the middle stage in the process of coal formation. It contains less than 40 percent carbon. It has more impurities. The parts of the wood are remarkably present in it.
Issues associated with Coal mining and use of Coal
- Coal mining and use of coal in power stations and factories have led to degradation of the environment.
- Coal mining can cause contamination of drinking water. Power stations and factories that burn coal also consume large quantities of water.
- Combustion of carbon releases a number of greenhouse gases that is a major cause of global warming and climate change.
- Smog and acid rain are also due to the use of coal.
- Fly ash can also contaminate land and water.
- The use of coal as fuel causes adverse health problems and deaths. It is a leading cause of asthma, bronchitis, strokes, heart attacks, mercury poisoning, lung cancer.
- There is a global campaign going to decrease the dependence on coal and move to cleaner and more efficient fuels.
Distribution of Coal across the world
The coal deposits although exist in nearly every part of the world, but commercially exploitable coal reserves are found mainly in China, USA, India, Australia, Indonesia, Russia, Canada, South Africa, Columbia, Kazakhstan and Ukraine.
Although China has third largest coal reserves worldwide it is the biggest coal producer. Most coal reserves are located in the north and north-west of China, which poses a large logistical problem for supplying electricity to the more heavily populated coastal areas. Majority of the proven coal reserves in China are found in Northern Shansi, Shensi and Inner Mongolia. Other major coal mining areas are Heilongjiang, Jilin, Liaoning, Henan and Shandong.
The USA has the largest coal reserves worldwide and is also one of the largest coal producers. The coal reserves are widely distributed across the country. Major coal mining areas in the USA are Appalachian, Montana, Wyoming, Illinois, Indiana, western Kentucky, West Virginia, Alabama, Pennsylvania, Ohio, Missouri, Michigan and Texas.
Russia has the second largest coal reserves worldwide and is the sixth-largest producer. Major coal reserves include Donetskii in Moscow, Pechora basins in western Russia and the Kuznetski, Kansk-Achinsk, Irkutsk and South Yakutsk basins in Eastern Russia, Kansk-Achinsk Basin and the Raspadskaya mine in the Kemerovo region
Australian has fourth largest coal reserves in the world and largest in the Southern Hemisphere. Major coal mining areas are New South Wales, Queensland and Victoria.
Canada s major coal reserves are located in sedimentary basins of Nanaimo, Bowser, Skeena, Moose River, Maritime and Bowron River.
Prominent coal reserves of Germany are in the regions of Ruhr Coal Basin in the North Rhine-Westphalia state, Saar Basin in the south-west Germany, Rhineland region and Garzweiler.
Most of Ukraine s coal reserves are found in Donets Basin in Eastern Ukraine. The Donets Basin is spread across three Ukrainian provinces - Donetsk, Dnipropetrovsk and Luhansk.
South Africa accounts for majority of coal production in Africa. The prominent coal mining regions of South Africa areas are Transvaal, Cape of Good Hope and Natal.
Major coal mining regions in Kazakhastan are Karaganda, Ekibastuz, Turgay, Nizhne-Iliyskiy and Maikuben basin.
Colombia has the biggest coal reserves in South America. Major coal reserves are in Guajira peninsula. Correjon is the biggest coal mine in Colombia, followed by the La Loma coal mine.
Distribution of Coal in India
In India, about 97 percent coal is of Gondwana type and remaining is the Tertiary type.
Coal Reserves (in descending order):
- West Bengal
- Madhya Pradesh
Coal reserves are widely distributed across India
- The Damodar Valley Coalfield- It is the largest coal reserve in India. The coalfield area includes the states of Jharkhand and West Bengal. Jharia of Jharkhand is the largest coalfield of India. Most of the coking coal in India is obtained from here. Other coalfields in Jharkhand are Jayanti, Bokaro, Karanpura, Ramgarh, Giridh, Auranga, Hutar, Deltenganj and Deogarh. Major coalfields in West Bengal are Raniganj (oldest coalfield of India) and Dalingkot in Darjeeling district.
- The Son Valley Coalfield- The region of Madhya Pradesh and some areas of Uttar Pradesh are included in it. Prominent coalfields in the Son Valley are Singrauli, Sohagpur, Umaria, Pench, Ramkola and Tatapani.
- The Mahanadi Valley Coalfield- The areas of Chhattisgarh and Odisha are included in it. Major coal mining areas in Chhattisgarh are Korba, Jhilmil, Chirmiri, Vishrampur, Lakhanpur, Sonhat, Birampur and Sonhat. Talcher, Rampur-Himgir and Ib river coalfield is the prominent coalfields in Odisha.
- The Godavari Valley Coalfield- The region is in the states of Andhra Pradesh and Telangana. Major coalfields in the region are Singreni, Tandoor and Sasti.
- The Wardha Valley Coalfield- Kampti, Wunfield, Chandrapur, Yavatmal, Nagpur are major coal mining areas located in Maharashtra.
- The Satpura Coalfield- The region is in the Satpura range, south of the Narmada river. Major coal mining centres are Ghorbari, Mahapani and Patharkheda.
- The Rajmahal Coalfield- Major coal-mining centre in the Rajmahal range is Lalmatia where open-cast mining is practised.