1. Petroleum

2.  Petroleum is a naturally occurring liquid mixture that contains mainly hydrocarbons  Petroleum also contains oxygen, nitrogen and sulphur compounds.  Petroleum is widely referred to as “black gold”.  It is found mainly in the Middle East.

4.  Oil is ultimately derived from solar energy.  The energy stored in oil initially came from the sun and was incorporated into plants and animals through the process of photosynthesis.  Millions of years ago when marine life died, they settled to the bottom of the sea and was buried in layers of clay, silt and sand.  As these fossils became heated and pressured they formed hundreds of compounds.

5.  In order to form economically recoverable amounts of petroleum, an oil pool and an oil trap are needed.  An oil pool is an underground reservoir of oil.  This oil pool may be a literal pool or a highly porous rock.  An oil trap is a non-porous rock that holds the oil in place.

6.  A reservoir rock is used to ensure that the oil and associated gas stays in the ground.  The reservoir rock is covered in impervious rock to ensure the hydrocarbon fluids do not pass through the surface.

9.  To extract petroleum from the earth, a well is drilled.  To drill a well, detailed knowledge of the geological features of the land is to known.  There are two ways in which petroleum can be recovered from the earth, these include primary and secondary methods.

10.  Primary or conventional methods only acquire 30% of oil.  There are three ways in which primary recovery can occur. These are flush production, settled production and enhanced pumping.  Flush production occurs where natural pressure forces within the earth push the oil to the surface.  Settled production occurs where the oil has to be pumped.

11.  This is where flush production is duplicated artificially by flooding the field with water to push the oil up or gas is pumped down a well to create an artificial gas cap drive.

12.  Tertiary or secondary methods are sometimes utilized though they are more expensive.  These methods are only used on the account of decreasing the viscosity of the oil to enable further recovery.  This method involves injecting heat into the earth or using special chemicals.

13.  Oil is transported using pipelines and tankers.  Tankers usually transport up to 50 million barrels of oil.

14.  When fractional distillation has taken place, five main categories of petroleum are attained.

15. PetroleumUses GasIndustrial and Residential Fuel GasolineSpark-ignition engines Diesel FuelCompression-ignition engines Jet fuelJet engines and gas turbines Fuel OilIndustrial and Residential Fuel

16.  When transporting oil in tankers, oil spills may occur which damage aquatic life.  Loss or agricultural land due to drilling platforms, roads, and storage facilities.  Land subsidence(sinking), as oil and gas are withdrawn.  Oil seepage into the sea from normal operation and large spills.