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General FAQ

Q: What is oil?
Crude oil is the mixture of petroleum liquids and gases (including impurities such as sulphur) that is pumped out of the ground by oil wells.

What is oil? Together with natural gas, it makes up petroleum, which is Latin for "rock oil". Petroleum is basically a mix of naturally occurring organic compounds from within the earth that contain primarily hydrogen, carbon and oxygen. When petroleum comes straight out of the ground as a liquid it is called crude oil if dark and viscous, and condensate if clear and volatile. When solid it is asphalt, and when semi-solid it is tar. There is also natural gas, which can be associated with oil or found alone.

Crude oil comes in many forms. Usually it is black, but green, red or brown oils are not uncommon. Thin and volatile oils are called "light", whereas thick and viscous ones are "heavy". Light oils have an API gravity of 30 to 40 degrees, which means that the density is much less than 1.0 g/cc. These oils float easily on water. By contrast, some heavy oils have an API gravity of less than 12 degrees and are so dense that they sink, rather than float, in water.

It can be a straw-colored liquid or tar-black solid. Red, green and brown hues are not uncommon.
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Q: What is natural gas?

Natural gas is a naturally occurring mixture of hydrocarbon and non-hydrocarbon gases. The principal constituent is methane, which is the simplest hydrocarbon. Natural gas is colorless, shapeless and odorless. It is energy dense and clean burning.

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Q: How were oil and natural gas formed?
Most scientists believe that oil and natural gas was formed about 300 million years ago during the Carboniferous period of the Paleozoic era. Petroleum began to form as plant and animal remains decayed in sediments at the bottoms of oceans, lakes and streams. Over time, massive amounts of pressure and high temperatures converted the organic matter into oil and gas. Sometimes these oil and gas accumulation became trapped in rock formations. Today, oil companies study these rock formations in their search for oil and natural gas. When they find a formation that is likely to contain petroleum, the company drills a well.
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Q: What is oil used for?
Many people are surprised by how many products are created using petroleum products. Some products are obvious: gasoline, jet fuel, motor oil, lubricants, waxes, kerosene and asphalt. Others, such as plastic and fertilizer, are not commonly associated with oil. According to the U.S. Department of Energy (http://tonto.eia.doe.gov/ask/crudeoil_faqs.asp), a 42 gallon barrel of oil yields:

(Percentages equal more than 100 because of an approximately 5% processing gain from refining.)
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Q: What is natural gas used for?

Natural gas is used to generate electricity and heat homes and businesses. It is also used for cooking, washing and drying, and as a transportation fuel.
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