<human>:  What causes fossil fuel depletion?
<bot>: Fossil fuel depletion occurs due to an increase in the demand for energy coupled with a decrease in the supply of fossil fuels. This occurs because fossil fuels, like oil, natural gas, and coal, are finite resources: once they've been extracted and used, they are gone forever. Additionally, as the world population quickly grows, the demand for energy produced from fossil fuels usually increases faster than the supply.