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Facts
Non-renewable resources exist in a fixed amount and can only be replaced by
processes that take millions of years. If they are depleted, they are depleted for good.

What is a Fossil Fuel?
Fossil fuels are the fuels formed from ancient organic ma er. Coal, oil, and natural are
fossil fuels. Coal is actually a sedimentary rock that was originally formed from ancient
plant ma er through decomposi on and millions of years of
compac on. Coal, made of carbon, is by far the most
abundant fossil fuel in the world. The eastern and Midwestern
U.S. have abundant coal seams that formed during the
Pennsylvanian Period (300 ma), when the region was located
close to the equator.

How do fossil fuels form?
Fossil fuels are formed from the decomposed remains of past
life over millions of years under large amounts of pressure and
high temperatures. As marine organisms, called plankton, die
and fall to the seafloor, they are covered by sediment. A er
they are buried deeply enough, pressure and heat cause the
dead plankton to change to oil and gas.

How can we find fossil fuel?
There are specific but known condi ons that must be met in order to find the oil and
gas. Oil and gas are usually found within a permeable rock such as sandstone.
Permeable simply means that the rock is porous, and liquids or gases can easily flow
through it.

A finer grained sedimentary rock, like shale, is rela vely impermeable. Fluids cannot
easily flow, but they form good boundaries for trapping gas or oil. These rock
boundaries are some mes called a roof or trap rock. If a layer of sedimentary rocks is

lted upwards with shale on top of sandstone, the natural gas will rise upward since it
is less dense than water, the gas is trapped by the layer of shale.

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