About 24 hydrocarbon accumulations have been discovered in the Campos Basin, including four giant fields in shallow to moderate water depths, in the period from 1978 to 1988.

Linguado field is located in the extreme south of the producing area of Campos Basin, in water depths ranging from 95 to 110 m. The pool was discovered by the wildcat 1-RJS-49 in May 1978. The reservoir rocks, which occur between -1700 and -3000 m, are Hauterivian fractured basalts, Barremian pelecypod coquinas, Albian oolitic and oncolitic calcarenites, and, secondarily, Cretaceous turbidite sandstones. The main reservoir is formed by coquinas, which contain 80% of the total original recoverable oil volume, estimated at 130.15 million bbl. The field is located on a regional high, and the accumulation is strongly controlled by stratigraphic and diagenetic factors. High-quality oil (29 to 32° API) is produced through two floating production systems, and the cumulative oil productio amounted to 82.25 million bbl as of December 1990.

Carapeba and Vermelho fields are situated at the northern limit of the Campos Basin producing area and, together with the smaller Pargo field, make up the so-called Northeastern Pole of the Campos Basin. Carapeba was discovered in February 1982 by the wildcat 1-RJS-193A and has an estimated recoverable oil volume of 183.81

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million bbl. Production comes mainly from two Late Cretaceous turbidite sandstone reservoirs. Vermelho field was discovered by the wildcat 1-RJS-241A in December 1982, and its main reservoir is formed by a massive Eocene turbidite sandstone. The estimated recoverable oil volume amounts to 121.55 million bbl. Both Carapeba and Vermelho fields are structural traps associated with the development of subtle anticlines caused by salt tectonics. The fields are gradually being put on stream through five fixed platforms installed in water depths ranging from 70 to 90 m.

Marimba field, discovered in March 1984 by the wildcat 1-RJS-284 drilled in a water depth of 383 m, is considered the first deep water oil strike in Campos Basin. The field has an estimated recoverable volume of 174.18 million bbl of good-quality (28° API) oil in highly permeable Late Cretaceous turbidite sandstones, trapped under structural-stratigraphic conditions. The Marimba field has not yet been completely developed, but a floating production system is producing about 22,000 BOPD from four exploratory wells completed in water depths ranging from 383 to 485 m.