Oil and gas a called fossil fuels. They were formed by the sedimentation and fossilization of plants and animals.
When plants near the sea, or tiny sea creatures died, they fell to the bottom of the sea or lake and formed a layer of organic matter. These layers were then covered by layers of sand or other sediment.
As the layers of sediment built up and other changes happened in the crust of the earth, such as volcanic activity or distortion of tectonic plates the organic matter was squeezed and put under pressure and high temperatures.
These high pressures and temperatures changed the organic matter into coal, oil and gas. All three fossil fuels are based on carbon chain molecules called hydrocarbons. Coal contains the largest molecules, oil intermediate length molecules and gas the smallest molecules. Natural gas is mainly made up of methane which is one carbon atom bonded to four hydrogen atoms.
When plants near the sea, or tiny sea creatures died, they fell to the bottom of the sea or lake and formed a layer of organic matter. These layers were then covered by layers of sand or other sediment.
As the layers of sediment built up and other changes happened in the crust of the earth, such as volcanic activity or distortion of tectonic plates the organic matter was squeezed and put under pressure and high temperatures.
These high pressures and temperatures changed the organic matter into coal, oil and gas. All three fossil fuels are based on carbon chain molecules called hydrocarbons. Coal contains the largest molecules, oil intermediate length molecules and gas the smallest molecules. Natural gas is mainly made up of methane which is one carbon atom bonded to four hydrogen atoms.