<P> Headquartered in Dhahran, Saudi Arabia, Saudi Aramco operates the world's largest single hydrocarbon network, the Master Gas System . Its 2013 crude oil production total was 3.4 billion barrels (540,000,000 m), and it manages over one hundred oil and gas fields in Saudi Arabia, including 288.4 trillion standard cubic feet (scf) of natural gas reserves . Saudi Aramco operates the Ghawar Field, the world's largest onshore oil field, and the Safaniya Field, the world's largest offshore oil field . </P> <P> Saudi Aramco's origins trace to the oil shortages of World War I and the exclusion of American companies from Mesopotamia by the United Kingdom and France under the San Remo Petroleum Agreement of 1920 . The US Republican administration had popular support for an "Open Door policy", which Herbert Hoover, secretary of commerce, initiated in 1921 . Standard Oil of California (SoCal) was among those US companies seeking new sources of oil from abroad . </P> <P> Through its subsidiary company, the Bahrain Petroleum Co . (BAPCO), SoCal struck oil in Bahrain in May 1932 . This event heightened interest in the oil prospects of the Arabian mainland . On 29 May 1933, the Saudi Arabian government granted a concession to SoCal in preference to a rival bid from the Iraq Petroleum Co...The concession allowed SoCal to explore for oil in Saudi Arabia . SoCal assigned this concession to a wholly owned subsidiary, California - Arabian Standard Oil (CASOC). In 1936, with the company having had no success at locating oil, the Texas Oil Co . (Texaco) purchased a 50% stake of the concession . After four years of fruitless exploration, the first success came with the seventh drill site in Dhahran in 1938, a well referred to as Dammam No. 7 . This well immediately produced over 1,500 barrels per day (240 m / d), giving the company confidence to continue . On 31 January 1944 the company name was changed from California - Arabian Standard Oil Co. to Arabian American Oil Co. (or Aramco). In 1948, Standard Oil of New Jersey (later known as Exxon) purchased 30% and Socony Vacuum (later Mobil) purchased 10% of the company, with SoCal and Texaco retaining 30% each . The newcomers were also shareholders in the Iraq Petroleum Co. and had to get the restrictions of the Red Line Agreement lifted in order to be free to enter into this arrangement . </P> <P> In 1950, King Abdulaziz threatened to nationalize his country's oil facilities, thus pressuring Aramco to agree to share profits 50 / 50 . </P>

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