Crude Oil and Natural Gas: How Petroleum Forms Beneath the Earth
Modern civilization depends heavily on petroleum. Petrol and diesel power vehicles. Jet fuel powers aircraft. Natural gas supplies energy and industrial feedstock. Petroleum-derived materials contribute to plastics, chemicals, lubricants, paints, synthetic materials and numerous manufactured products. Yet crude oil begins far from the refinery. Its story starts with geology, organic matter, sediment, heat, pressure and enormous periods of geological time. What Is Petroleum? The word petroleum broadly refers to naturally occurring hydrocarbon-rich materials found within Earth's geological formations. Two especially important forms are: Crude oil — petroleum that occurs predominantly as a liquid under appropriate reservoir and surface conditions. Natural gas — gaseous hydrocarbons, typically dominated by methane. Crude petroleum is not one pure chemical substance. It is a complicated mixture containing many different hydrocarbons along with smaller quantities of compounds containing...