The giant Albacora and Marlim fields are located in the northeastern portion of the Campos Basin, offshore Brazil, in water depths ranging from 250m (820ft) to 2,000m (6,562ft). The "Marlim Complex", which encompasses the Marlim Field itself (152km2 or 59mi2) and some adjacent proved and potential areas, has a total surface of about 350 km2 (135mi2), while the Albacora Field is approximately 235km2 (91mi2) in area. The present estimate of oil in place is about 13.9 billion barrels for the "Marlim Complex" and 4.5 billion barrels for the Albacora Field. While in Albacora, oil production is from Cretaceous and Tertiary (Eocene, Oligocene, and Miocene) reservoirs, in the Marlim Field the potential producing reservoirs are mainly Oligocene turbiditic sandstones.
Turbidite deposits are genetically associated with sea-level variations caused by either tectonic or eustatic events. From electric log correlations and detailed core analyses, the reservoir facies are composed mainly of massive sandstones, and subordinately of contourites, and sandstones with the Bouma Cycle. Non-reservoir facies include laminated shales, pebbly mudstones, and hemipelagic marls.
In addition to mapping the reservoirs, 3-D seismic data are being extensively used as a primary tool for helping in the development of the Albacora and Marlim fields.
The development of technology for the exploitation of hydrocarbons from waters deeper than 500m (1,640ft) is of utmost importance. In the Albacora Field, this will be accomplished by obtaining reservoir data through strategic wells drilled at waters deeper than 500m (1,640ft), while producing from areas shallower than 400m (1,312ft). The technology to develop the Marlim Field will be obtained through a pilot project to be implemented in an area with water depths varying from 600m (1,970ft) to 800m (2,625ft).
The Albacora and Marlim fields are located about 110km (68mi) offshore Cape São Tome, in the northeastern portion of the Campos Basin (Fig. 1), in water depths ranging from 250m (820 ft) to 2,000m (6,562 ft).
The Albacora Field was discovered in September 1984. The wildcat 1-RJS-297 (Fig. 1) was drilled in 293m (961ft) of water. Later on, the wildcats 1-RJS-305 and 1-RJS-342 extended the field limit to deeper waters. Currently, the Albacora Field is aproximately 235km 2 (91mi 2) in area, and the estimate of oil in place is about 4.5 billion barrels.
The Marlim Field was discovered in February 1985 by the wildcat 1-RJS-219A (Fig. 1), in a water depth of 853m (2,800 ft). The present areal extent of the Marlim Field is 152km 2 (59mi2) and the latest estimate of oil in place is about 8.2 billion barrels.
The Marlim Complex encompasses the Marlim Field itself and the surrounding potential areas (Fig. 1) East-of-Marlim (70km2 or 27mi2), West-of-Marlim (20km 2 or 7.7mi2), and South-of-Marlim (127km 2 or 49mi2).
