Heavy oil production operations in Potiguar Basin, Brazil

The Potiguar basin is located on the northeastern Brazilian coast and comprises an onshore portion with 21,500 km2 (8300 mi2) and its offshore extension (Fig. 1). In the last 4 years, many oil fields have been discovered in the onshore portion, where today's production reaches 20,000 bbl/d. The oil accumulations are mainly structural, from three clastic reservoirs: Lower Cretaceous (Neocomian to Aptian) Pendencia and Alagamar formations, and Middle Cretaceous Acu Formation (Fig. 2). The Upper Cretaceous Jandaira Formation (carbonates) and Tertiary units offshore complete the stratigraphic column of the basin. The purpose of this paper is to present a summary of regional reservoir studies (Castro et al., 1982), Petrobras internal reports, and the engineering data relating to the three heavy - oil fields - Fazenda Belem, Alto do Rodrigues, and Estreito - with particular reference to the exploitation methods applied.