: Country comparison: Oil proven reserves

Oil and gas operations commenced in Nigeria effectively in 1956, with the first commercial find in that year by the then Shell D'Arcy. Before this time, almost the entire country was covered by a concession granted to the company to explore for petroleum resources since November 1938. This dominant role of Shell in the Nigerian oil industry continued for many years, until Nigeria's membership of the Organisation of Petroleum Exporting Countries (OPEC) in 1971, after which the country began to take a firmer control of its oil and gas resources, in line with the practice of other members of OPEC. This period witnessed the emergence of National Oil Companies (NOCs) across OPEC member countries, with the sole objective of monitoring the stake of the oil producing countries in the exploitation of the resource. Whereas in some OPEC member countries, the NOCs took direct control of production operations, in Nigeria, the Multinational Oil Companies (MNOCs) were allowed to continue with such operations under Joint Operating Agreements (JOA) which made clear provisions for the respective stakes of the companies and the Government of Nigeria in the ventures.