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How are petroleum and natural gas related to hydrocarbons?
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hydrocarbon
Structures assumed by hydrogen (H) and carbon (C) molecules in four common hydrocarbon compounds.
Petroleum and natural gas are both primarily composed of hydrocarbons, which are organic chemical compounds consisting exclusively of carbon and hydrogen atoms.1
- Petroleum: This is a complex mixture of hundreds of different hydrocarbons, typically containing about 82 to 87 percent carbon and 12 to 15 percent hydrogen by weight. It forms from the thermal degradation of kerogen within sedimentary source rocks during a process known as the mature stage.234
- Natural Gas: This is a hydrocarbon mixture consisting primarily of light, saturated paraffins such as methane and ethane. While it is often found alongside petroleum, it can also be generated independently from coal deposits or through the thermal breakdown of organic matter at greater depths.543
Because they are composed of these carbon-hydrogen structures, both substances serve as vital fossil fuels and essential raw materials for the production of plastics, rubbers, and various industrial chemicals.1