1. Photosynthesis:
* Plants, through photosynthesis, absorbed carbon dioxide (CO2) from the atmosphere and used it to create organic compounds (like sugars, cellulose, and lignin).
* This process captures carbon from the atmosphere and stores it in the plant's tissues.
2. Decay and Burial:
* When these plants died, they were buried under layers of sediment (sand, silt, clay).
* Over time, the sediment layers compressed and formed rock, trapping the organic matter.
3. Transformation:
* The buried organic matter experienced heat and pressure from deep within the Earth.
* This transformed the organic matter into hydrocarbons (molecules made of hydrogen and carbon).
* Depending on the specific conditions of pressure, temperature, and time, different types of fossil fuels formed:
* Coal: Formed from ancient forests and peat bogs.
* Oil: Formed from ancient marine organisms like algae and plankton.
* Natural Gas: Formed from both plant and animal matter, often alongside oil deposits.
In essence, the carbon in fossil fuels is ancient carbon that was originally captured from the atmosphere by living organisms and then stored underground for millions of years.
