About 300 million years ago the earth had dense ________ in low-lying wetland areas. Due to natural processes, like ______, these forests got buried under the ________. As more ________ deposited over them, they were compressed. The ________ also rose as they sank deeper and deeper. Under high ________ and high ________, dead plants got slowly converted into coal.
About 300 million years ago the earth had dense ________ in low-lying wetland areas. Due to natural processes, like ______, these forests got buried under the ________. As more ________ deposited over them, they were compressed. The ________ also rose as they sank deeper and deeper. Under high ________ and high ________, dead plants got slowly converted into coal.
- Coal beds consist of altered plant remains. When forested swamps died, they sank below the water and began the process of coal formation. However, more than a heavy growth of vegetation is needed for the formation of coal. The debris must be buried, compressed and protected from erosion. Even though all the biological, geographic and climatic factors may be favourable, coal could not be formed unless the plant debris was submerged and buried by sediments.
- There are four stages in coal formation: peat, lignite, bituminous and anthracite. The stage depends upon the conditions to which the plant remains are subjected after they were buried – the greater the pressure and heat, the higher the rank of coal. Higher-ranking coal is denser and contains less moisture and gases and has a higher heat value than lower-ranking coal.
Therefore, about 300 million years ago, the earth had dense forests in low-lying wetland areas. Due to natural processes, like floods, these forests got buried under the earth's surface. As more soil was deposited over them, they were compressed. The pressure also rose as they sank deeper and deeper. Under high temperature and high pressure, dead plants got slowly converted into coal.
- Coal beds consist of altered plant remains. When forested swamps died, they sank below the water and began the process of coal formation. However, more than a heavy growth of vegetation is needed for the formation of coal. The debris must be buried, compressed and protected from erosion. Even though all the biological, geographic and climatic factors may be favourable, coal could not be formed unless the plant debris was submerged and buried by sediments.
- There are four stages in coal formation: peat, lignite, bituminous and anthracite. The stage depends upon the conditions to which the plant remains are subjected after they were buried – the greater the pressure and heat, the higher the rank of coal. Higher-ranking coal is denser and contains less moisture and gases and has a higher heat value than lower-ranking coal.
Therefore, about 300 million years ago, the earth had dense forests in low-lying wetland areas. Due to natural processes, like floods, these forests got buried under the earth's surface. As more soil was deposited over them, they were compressed. The pressure also rose as they sank deeper and deeper. Under high temperature and high pressure, dead plants got slowly converted into coal.
