Coal still remains an important source of fuel. Efforts to produce and use coal in a non-polluting manner will continue for many years.
Coal forms when dead plant life slowly decays and remains under pressure for several centuries.
Plant life decays very slowly in boggy environments; it actually may not decay completely. This material accumulates at the rate of about one foot for every ten years of decomposition. As layer upon layer of decaying matter pile up, the lower compressed layers turn into peat. In some areas peat has been used as a source of fuel.
Over time and under continued compression, a 20-foot layer of the peat will gradually turn into a more useful fuel: bituminous coal.
How long does this transformation take? Scientists have estimated that it takes about 300 years of growth, death, decay and compression for vegetation to move through the stages of plant to compost to peat to coal.
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