past:
present:
How Fossil Fuel Is Formed
Fossil fuel was formed over hundreds of millions
of years ago by decomposing plants. After a long period of time, layers
and layers of rock, mud, and sand covered the dead plants thousands of
feet under the earth, which fossilized them.
Oil and natural gas were formed the same way, but coal was formed
a slightly different way. The first two were formed by organisms - plankton
and plants mostly - that lived in fresh water and they were buried under
rivers and oceans. After a long period of time the water receded back.
The pressure and bacteria combined to make oil 
and natural gas. Oil and natural gas started to rise
up from under ground but then it stopped, because of caprock, really hard
rock that these two cannot move through. The caprock holds them back so
that they cannot spill to the surface. When the petroleum companies drill
down through the caprock, if they are lucky they find oil and natural
gas under them, and that’s how it is captured today.
Coal is formed almost the same way but different. It was created
by dead remains of trees, ferns and other plants that lived 300 to 400
millions of years ago. Coal was found in swamps covered by seawater. Since
the 
sea has a lot of sulfur it stayed behind in the coal, when the water receded.
Unless it is removed when it is being burned, the sulfur goes into our
air when the coal is burned, In some parts of the world there were freshwater
swamps, coal from here has less sulfur and is much cleaner then the other
swamps.
In many ways oil, natural gas, and coal are formed the same way. In the future maybe scientists will take the sulfur from coal so we would not have air pollution. But since they were all produced over millions of years, in the future we will run out of all the types of fossil fuel. We are using them up much faster than they can be produced and fossil fuel plants are where most of our electricity comes from now.
Fossil Fuel Team: Christyn, Ashley, Mercedes, Veronica
( Thanks to the Department of Energy for the graphics here! See our Resources page.)