Definition Of Petroleum

	Petroleum (L. petroleum, from Greek: petra (rock) + Latin: oleum (oil)) or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from gasoline and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals.           The term petroleum was first used in the treatise De Natura Fossilium, published in 1546 by the German mineralogist Georg Bauer, also known as Georgius Agricola.[3] In the 19th Century, the term petroleum was frequently used to refer to mineral oils produced by distillation from mined organic solids such as cannal coal (and later oil shale), and refined oils produced from them; in the United Kingdom storage (and later transport) of these oils were regulated by a series of Petroleum Acts, from the Petroleum Act 1862 c. 66 onward.