Fossil fuels are introduced as non-renewable sources, meaning the fossils we dig up to use will finally run out or continue to be harder to discover and extract.
Fossil fuels include coal, petroleum, natural gas, oil shales, bitumens, tar sands, and heavy oils.
Libavius was in contrast with those natural philosophers who theorized petroleum and coal having origin after chemical reactions and actions of endogenous forces below the crust e.
Butane is not as abundant as other hydrocarbons and it makes about 20% of natural gas.
We depend on those fuels to heat our homes, run our vehicles, power industry and manufacturing, and provide us with electricity.
It can even be used to produce carbon-neutral fuels.