Petroleum, named for "rock oil", is a fossil fuel usually found deep within the earth, although some deposits are very close to the surface.
It is a heavy dark liquid, consisting of many different hydrocarbon compounds. Crude oil is extracted from the ground and fractionated into its components by volatility in an oil refinery. Some of the main products distilled from crude oil are:
The following table[1] compares the qualities of various types of petroleum:
Fraction | API gravity | Viscosity (mp) |
Gasoline | 60 | 6 |
Kerosene | 50 | 20 |
Diesel | 45 | 100 |
Lubricating oil | 30 | 500 |
Residuum | 10 | >105 |
Origins
Oil deposits are often found in concurrence with natural gas in a variety of geological structural or stratigraphic traps.
Petroleum has an organic origin, being generally believed to be formed from the remains of vegetable material.
Secular geologists have contended that petroleum is the remains of huge amounts of algal material that was laid down millions of years ago, and altered in form under high temperatures and pressures. Layers of buried plant material tend to produce coal or lignite.
Creationary geologists believe that petroleum was formed from organic material buried during the Noachian flood.
Recently, researchers have shown that natural gas can form rapidly[2], and that some is still being formed.
This gives support to the creationary view. If this research is supported it would refute the idea that fossil fuels are diminishing.[Citation Needed]