Commercial reserve discoveries in the deep waters of Block 17 and neighboring Blocks (14, 15 and 16) marked the turning-point in the history of oil production in Angola. In 1996 when the reserves of Girassol were discovered in deep water on Block 17, Angola went from being a solid but average oil producing country to become a hotspot in the global search for major oil reserves.

Girassol, on Block 17

When Girassol came on stream in late 2001, the line on Angola's oil production graph moved upwards exponentially. It is a trend that is set to continue as more offshore fields are brought into production.

Thus far, deep water discoveries off Angola's Atlantic coast have reached success rates of about 80%. On Block 17, commercial discoveries were found in all drilled wells - Rose, Dahlia, Orchid, Jasmine, Tulip and Sunflower (Girassol in Portuguese).

The total oil production for Angola in 2001 was below one million barrels per day (bpd). By the end of 2005 production of crude in Angola surpassed 1.4 million bpd and that it will reach two million bpd in the first trimester of 2008.

With the fast-paced advance of drilling technology and the success of Blocks 15 and 17, there are great expectations for results of ultra-deep water (i.e. drilling at depths greater than 2.000 meters) exploration off Angola's coast.

Angolan ultra deep water Blocks are numbered 31 to 34. With reserves of blocks 31 and 32 estimated to be at about 800 million barrels within the next 15 years Angola may become one of the major oil producers in the southern hemisphere.

To know more about the blocks please consult the concessions map.

Geological heritage

Angola is made up of the Kwanza, Congo and Namibe sedimentary basins, but so far only the Congo and Kwanza basins have yielded oil in commercial quantities.

The southern coastal region of Angola remains unexplored after the failure of blocks 09, 21, 22 and 25 which are located offshore of southern Luanda. Drilling has also been unsuccessful off the coast of Namibia, Angola's southern neighbor, which has further discouraged exploration.

Engineers in Sonangol's geological department insist, however, that they want to begin a comprehensive survey of blocks in the Namibe basin, which they believe may yet produce surprises.

To date, it is clear that geology has favored blocks in the north of the country.

An example of success is Block Zero that lies off Cabinda and is situated just to the north of the Congo River. The proximity to the river is key. The concession's map shows that the biggest reserves fan out from the mouth of the river. It is thought that this is due to the deposit of large quantities of vegetable material which eventually became oil.

Hence the huge current interest in blocks beyond the range of existing discoveries.