Petroleum

Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name ''petroleum'' covers both naturally occurring unprocessed crude oil and petroleum products that consist of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, mostly zooplankton and algae, are buried underneath sedimentary rock and subjected to both prolonged heat and pressure.

Petroleum is primarily recovered by oil drilling. Drilling is carried out after studies of structural geology, sedimentary basin analysis, and reservoir characterisation. Recent developments in technologies have also led to exploitation of other unconventional reserves such as oil sands and oil shale.

Once extracted, oil is refined and separated, most easily by distillation, into innumerable products for direct use or use in manufacturing. Products include fuels such as gasoline (petrol), diesel, kerosene and jet fuel among many others; asphalt and lubricants; chemical reagents used to make plastics; solvents, textiles, refrigerants, paint, synthetic rubber, fertilizers, pesticides, pharmaceuticals, and thousands of others. Petroleum is used in manufacturing a vast variety of materials essential for modern life, and it is estimated that the world consumes about each day. Petroleum production can be extremely profitable and was critical to global economic development in the 20th century, with some countries, so called " oil states", gaining significant economic and international power because of their control of oil production.

Petroleum exploitation and use has had significant negative environmental and social consequences. Extraction, refining and burning of petroleum fuels all release large quantities of greenhouse gases, so petroleum is one of the major contributors to climate change. Other negative environmental effects include oil spills, and air and water pollution. Some of these effects have direct and indirect health consequences for humans. Oil has also been a source of conflict leading to both state-led-wars and other conflicts. Production of petroleum is speculated to reach peak oil before 2035 as global economies lower dependencies on petroleum as part of climate change mitigation and a transition towards renewable energy and electrification.

Etymology

The word ''petroleum'' comes from Medieval Latin (literally 'rock oil'), which comes from Latin petra 'rock' (from Greek ) and oleum 'oil' (from Greek ).

The term was used in the treatise '' De Natura Fossilium'', published in 1546 by the German mineralogist Georg Bauer, also known as Georgius Agricola. In the 19th century, the term ''petroleum'' was often used to refer to mineral oils produced by distillation from mined organic solids such as cannel 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 1863'' onwards.

History

Early

Petroleum, in one form or another, has been used since ancient times. More than 4300 years ago, bitumen was mentioned when the Sumerians used it to make boats. Tablet of the legend of the birth of Sargon of Akkad, mentioned a basket which was closed by straw and bitumen. More than 4000 years ago, according to Herodotus and Diodorus Siculus, asphalt was used in the construction of the walls and towers of Babylon; there were oil pits near Ardericca (near Babylon), and a pitch spring on Zacynthus. Great quantities of it were found on the banks of the river Issus, one of the tributaries of the Euphrates. Ancient Persian tablets indicate the medicinal and lighting uses of petroleum in the upper levels of their society.

The use of petroleum in ancient China dates back to more than 2000 years ago. The ''I Ching'', one of the earliest Chinese writings, cites that oil in its raw state, without refining, was first discovered, extracted, and used in China in the