Abstract: Efforts, Results and Future Perspectives of the Petroleum Exploration in Brazil
LUCCHESI, CELSO FERNANDO, Petrobras
The Brazilian sedimentary areas cover about 6,436,000 km2 of onshore and offshore basins up to water depths of 3,000 meters. Around 1,540,000 km2 correspond to offshore basins in which 50% represent deep-water regions (water depths greater than 400 meters). To date, 2,677 wildcats were drilled, only 77 of them in water depths greater than 400 meters and 75% were located in the Campos basin. Regarding seismic surveys, around 1.6 million km of 2D and 3D data were acquired, 25% of them in deep-water regions.
The exploratory efforts resulted in the discovery of more than 19 billion barrels of total reserves of equivalent oil. So far, more than 5 billion barrels were produced, and the remaining reserves reach 14,1 billion barrels. Today, 68% of the oil reserves are offshore, in water depths greater than 400 meters. Most of these reserves are accumulated in stratigraphic traps, in Upper Cretaceous and Tertiary giant deep-water turbidite systems. The natural gas reserves, by contrast, are concentrated onshore, mainly in Paleozoic sandstones of the Solimoes basin.
Concerning the Brazilian petroleum potential, the deep-water basins account for 60% of the total, most of them located in the Campos, Santos, Espirito Santo and Cumuruxatiba basins. It is important to mention that expressive potential for natural gas occurs in the Miocene/Eocene turbidites (Foz do Amazonas and Espirito Santo basins) and in deeper and older targets within other producing offshore basins. Onshore basins contribute with 25% of the total Brazilian potential (mainly natural gas) and most of this is expected to be in the Solimoes basin.
The discrete exploratory efforts performed in the areas referred above, as well as their high hydrocarbon potential, led us to the conclusion that those areas are in their early exploratory stage and expressive amounts of oil and gas are expected to be discovered.
AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah