Coal Formation

The formation of coal can be traced back to 300-400 million years ago. Coal was formed from the remains of swamp plants. This happened because the plants became buried in the swamp, and since they were buried, they received no oxygen. This caused the plants to not rot, but instead, to form peat. The heat value of peat is very low compared to coal. Sediment covered and compressed this peat nearly 80%. So after more heat and pressure, the peat turns to lignite. And with even more heat and pressure, the lignite turns into coal. There are three different kinds of coal: lignite, which is brown coal; bituminous, black coal, which is what we (WV) have, which is also the most common, and anthracite, which is hard coal. Anthracite is also a metamorphic coal while the rest are sedimentary.