This 'list of
oil fields' includes major fields of the past and present. The list is incomplete; there are more than 40,000 oil and gas fields of all sizes in the world
[1].

USGS map of countries where oil is located
However, 94% of known oil is concentrated in fewer than 1500 giant and major fields
[2]
N.B. Some of the items listed are basins that are composed of many fields (e.g. Campos Basin). The largest discovered conventional oil field is the
Ghawar Field (75-83 billion); some unconventional oil fields, such as tar sand deposits, contain even greater reserves like Venezuela's Orinoco Tar sands which contain the biggest oil reserves in the world.
Amounts given are estimated ultimate recoverable resources (proved reserves plus cumulative production) in
barrels. Non-conventional sources, such as
Oil shale reserves are not included in this chart.
See also
★
List of natural gas fields
★
Oil shale reserves
References
1. Schlumberger World Energy Atlas
2. Ivanhoe, L. F, and G G. Leckie, -"Global oil, gas fields, sizes tallied, analyzed," Oil and Gas Journal. Feb. 15, 1993, pp. 87-91
3. "Oil provinces" are larger than "petroleum systems" and characterized by a stratigraphic sequence and a tectonic stetting. The partition of oil provinces, and their names, can change from source to source. The names used here are from USGS.
4. http://www.saudiaramco.com
5. Chron.com-A first: Shell plans to produce at 8,000 feet in Gulf
6. www.finanznachrichten.de-Chevron Announces It Is Proceeding With a Major Oil Field Development Project in the U.S. Gulf of Mexico's Ultradeep Water