Natural gas was formed
millions of years ago when most of the earth was covered by water. Plant and
tiny animal remains were mixed and layered with sand and mud. When the Earth
underwent natural but drastic changes to form today's landscape, the intense heat and pressure transformed
these fossils into
hydrocarbons-chemical compounds of hydrogen and carbon atoms.
Depending on the
arrangement of the atoms, what were once sea plants and animals are now natural
gas or crude oil deposits contained in the earth's crust. Natural gas (a combustible, gaseous mixture of simple
hydrocarbons) is a very light portion of petroleum, which includes both natural
gas and crude oil. Natural gas may rise to the surface through natural openings
in the earth's crust or can be brought to the surface through man-made wells.
Humans discovered thousands of years ago that this naturally occurring resource
could be burned and used for heat and light. Today, natural gas continues to be
a safe, efficient, environment friendly and abundant energy source, and new uses
for it are still being discovered. In its natural state you can't see or smell natural gas. It is
colorless, odorless and lighter than air. Mercaptan, a chemical odorant, which
smells like rotten eggs, is added to natural gas so it can be smelled if it
Natural gas is made up mostly of methane, which has a simple
hydrocarbon structure of one carbon atom and four hydrogen atoms (CH4). This
means it burns easily and emits less pollution.
Natural gas will not by itself burn. Combustion can occur only
when there is a mixture of gas and air - containing between 5% and 15% natural
gas and between 85% and 95% air.
When natural gas is burned, it produces mostly carbon dioxide
and water vapor-the same substance emitted when people breathe. Compared with
other fossil fuels, natural gas emits the least amount of carbon dioxide into
the air as it is used-making natural gas the cleanest burning fossil