Angola is the seventh largest country in Africa, divided in 18 provinces and situated in the southwest of the continent, in the tropical zone of the southern hemisphere. It has a wealth of natural resources, fertile albeit scarce farming lands, rich mineral deposits of diamonds, iron, bauxite, gold, manganese, uranium and natural gas, in addition to a considerable volume of oil reserves with a highly valuable production. Oil exploration in Angola was initially carried out onshore by state-owned company Sonangol, but later on production moved offshore, to the continental platform - far from war operations - and is currently carried out by numerous foreign companies, both European and North American, such as British Petroleum, Fina Total, Shell, Chevron and Texaco, Exxon Mobil, Statoil and AGIP, by means of oil rigs authorized by the State through production sharing agreements. This concession system has increased the search for oilfields, which in turn has enabled findings and crude oil production to increase in the last few decades, going from some 100,000 barrels per day in 1976 to 2,1 million barrels per day in 2009, which is 2.3% of world oil production at present.