How are fossil fuels made from fossils?
Coal, petroleum and natural gas are all fossil fuels. They are fossil fuels because they were formed from plants and animals that decayed, and then pressure, bacteria, and heat preserved them in the earth’s crust for millions of years. Eventually, these decayed plants and animals went through a chemical change and became fossil fuels, such as coal. Some of these fuels, like petroleum, were actually formed where salt water once covered the land. That’s why you may see oil rigs in the ocean. Coal is formed from dead plants and trees that sank to the bottom of swampy areas about 300 million years ago. The dead plants formed layers on the bottom of the swamp, and they turned into a soggy material called peat. Eventually, the surface of the earth changed, and sand, clay, and other minerals from rivers and oceans fell onto the peat. Sedimentary rocks were formed on top of the peat. Their weight caused pressure, and this pressure squeezed the water out of the peat. The “dry” peat continued to
