Fossil fuels are made from dead organic matter buried deep under the earth millions of years ago.
Over the years, the remains of the dead plant and animal matter were broken down by microorganisms through a process called anaerobic digestion leading to the formation of fossil fuels such as coal, oil, and gas.
Anaerobic digestion is a process by which the microorganisms break down biodegradable material in the absence of oxygen.
- Oil and gas are formed from marine organisms buried deep under the ocean bed
- Coal is formed from land vegetation buried deep under the surface of the land
Fossil fuels are categorized as nonrenewable energy sources because they take millions of years to form.
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