The first concession license to prospect and search for hydrocarbons in Angola was given to a firm called Canha & Formigal, whose operating company was Pesquisas Mineiras de Angola (PEMA). This concession covered an area of 114,000 km2 and included the whole of the onshore part of the sedimentary basins of the Congo and Kwanza rivers, between the present cities of Soyo, to the north, and Sumbe, to the south.

The first well to be drilled under this concession was the Dande nº1, located on the left bank of the river of that name. Drilling started on March 25th 1915 and a depth of 602 meters was reached, without result. First commercial discovery of oil occurred 40 years later, although modest it was in 1955 and it was called the ‘Benfica Field’. The well was drilled in the Kwanza River Basin near the city of Luanda, by Missão de Pesquisas de Petróleo (Oil Research Mission), a subsidiary of the Belgian Petrofina (or Purfina) Group.

Later, in July 1961, in the wake of work begun by the Research Mission, the operating company then known as Petrangol, discovered the first major field, the Tobias Field, in the Cape Ledo region, which not only allowed Angola to become self-sufficient in terms of crude oil but also put an end, once and for all, to the scepticism of many as to the existence, underground, of the precious ‘black-gold’ in Angola.

Current Onshore E&P
At the present the Angolan onshore comprises the land areas of the Congo, Kwanza, Benguela and Namib Basins and the interior Kassanje, Okawango and Owango basins. At this time the only basin in operation is the Lower Congo, in the onshore area of the Congo River, also known as the Soyo area.

The Congo Basin is now fully on stream. It is divided into two blocks, Cabinda North operated by Sonangol Pesquisa & Produção and Cabinda South operated by Rakoil. During 2007, the Cabinda Centre was out to tender.

The Soyo zone has been operated by the French company Total. However, the entire operation is shortly to be transferred to Somoil, a companhy that is entirely Angolan, which will have as its technical partner Sonangol Pesquisa & Produção. In the Kwanza Basin two new blocks, Block 10 and 11 are to be put out to tender for licensing, exploratory studies are to be carried out in the Kwanza Basin, and Sonangol itself is expected to perform the 2D seismic work.

With regards to the Benguela and Namib Basins, exploration is going ahead at both, especially field work, collection of samples and geological surveys.

In the inland Kassanje, Okawango and Owango basins a start was made to survey work in 2006 and aerogravimetric studies are now being performed over an area of about 100,000 km2, that is, across the whole of theses studies, with the aim to analyse the potential of these basins in production terms. According to the Sonangol Operations Manager, Severino Cardoso “Angola has huge onshore potential as well”.

Shortly awaited is the disclosure of the exploration policy to be followed in onshore oil exploration, since the conditions have now been created, both by the government and by Sonangol, to intensify this work with a view to making full use of its productive, and consequently economic, potential.