Essay On Coal Form

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How Does Coal Form?
Coal forms from the accretion of plant debris, usually in a swampy environment. When a plant perishes and falls into the swamp, the standing water of the swamp defends it from decay. Swamp waters are usually deficient in oxygen, which would react with the plant debris and cause it to decay. This absence of oxygen allows the plant debris to persist. In addition, insects and other organisms that might decay the plant debris on land do not endure well under water in an oxygen-deficient environment.
To form the thick layer of plant debris required to products a coal seam, the rate of plant debris accumulation must be more than the rate of decay. Once a thick layer of plant debris is molded, sediments such as mud or sand must bury it. These are naturally washed into the swamp by a flooding river. The weight of these materials contracts the plant debris and aids in its transformation into
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Bituminous coal is formed when a sub bituminous coal is imperiled to increased levels of organic metamorphism. It has a carbon content of between 77% and 87% on a dry ash free basis and a heating value that is much higher than lignite or sub bituminous coal. On the basis of volatile content, bituminous coals are subdivided into low volatile bituminous, medium volatile bituminous, and high volatile bituminous. Bituminous coal is often mentioned to as "soft coal"; however, this designation is a layman's term and has little to do with the hardness of the rock.
Anthracite Anthracite is the highest rank of coal. It has a carbon content of over 87% on a dry ash free basis. Anthracite coal usually has the highest heating value per ton on a mineral matter free basis. It is often subdivided into semi anthracite, anthracite, and meta-anthracite on the basis of carbon content in the coal. Anthracite is frequently referred to as "hard coal"; however, this is a layman's term and has little to do with the hardness of the
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