When detecting antinuclear antibodies (ANA) a similar indirect immunofluorescence (IIF) pattern may be produced by antibodies which correspond to different antigenic specificity or to diverse autoimmune disorders. To circumvent this problem, we used an immunoblotting against total antigen from HEp-2 cells (TA-HEp-2-C) which proved to be more specific and sensitive than IIF, since it detected up to 40 antigenic bands and an immunoblot pattern characteristic of each individual and unrelated to the fluorescence patterns of ANA. The analysis of immunoblot patterns is of great diagnostic value, since in patients with systemic lupus erythematosus (SLE) the antigenic zone is found between 21 and 48 kDa, whereas in other rheumatic diseases with or without positive ANA antibodies by IIF it is found between 14 and 21 kDa. Bands which appear after 50 kDa may or may not have pathological significance since they are present in most normal individuals. The use of reference sera allowed the identification in the extract of previously described antigens relevant to these diseases. Some patients showed bands which have yet to be reported and may be clinically significant on their own or in association with other autoantibodies. The long-term follow-up of these immunoblot patterns may prove to be of prognostic importance.

The Barracuda and Caratinga oil fields contain a combined in place volume of 4,100 MMBOE, and total reserves of 1,200 MMBOE. They were discovered in 1989 and 1994, respectively, in the south-central Campos Basin after a successful 3D seismic-based exploration in deep water. In these fields, seismic attribute analysis discriminates oil saturated Paleocene, Eocene and Oligocene sandstones encased in shales and marls. The reservoirs are turbidite sandstones, deposited in bathyal settings controlled by halokinetic-generated depocenters and grabens. The fields will be jointly developed due to their geographic proximity. A pilot production system composed of 12 wells started production in September, 1997. Future plans include ore three phases: Phase 1 will take place in the Barracuda field in water depths less than 950 m, where geologic uncertainties are smaller; Phase 2 includes the area of Caratinga field, in water depths less than 1050 m; and Phase 3 will cover deep-water areas of both fields. The Barracuda and Caratinga fields will be developed essentially with horizontal wells (44 in Phase 1,24 in Phase 2 and 3 1 in Phase 3), and 2 1 verticals wells (3 new and 18 already drilled). This paper presents the reservoir characterization, development strategy and production plans for the fields, which were prepared by a multidisciplinary team of reservoir geophysicists, geologists, and engineers. This report focuses on the Phase 1 of Barracuda field, which includes almost half of the wells to be drilled, and will be responsible for an estimated production of 270,000 BPD. Introduction The Barracuda and Caratinga oil fields are located in the south-central portion of the Campos basin, about 90 km offshore of Rio de Janeiro State, Brazil, at water depths ranging between 600 and 1200 m (Figure 1). These two giant oil accumulations cover a total area of about 234 km2, and contain in place volume of 2,700 and 1,400 MMBOE and total reserves of 780 and 420 MMBOE, respectively. The oils of the fields are 25 and 24 degree API, respectively. The Barracuda and Caratinga fields were discovered in 1989 and 1994, respectively, after a successful seismic-based exploration campaign by PETROBRAS in deep waters of the Campos Basin. During the exploratory phase, PETROBRAS drilled 16 wells in Barracuda (4 wildcats and 12 appraisal wells) and 10 wells in Caratinga (2 wildcats and 8 appraisal wells). The large number of appraisal wells indicates the complexity of the fields. Seventeen wells of these will be producers and one well will be a water injector. Some will be used during a pilot production phase in the monitoring of reservoir behavior. The future development and production plan for the areas is divided into 3 consecutive phases. From the 102 news wells planned to be drilled, 52 will be as producers and 50 as water injectors. Geologic Reservoir Characterization The Barracuda field has 4 stacked reservoirs of Late Paleocene, Middle Eocene (2 zones) and Late Oligocene age (Figure 2). All are turbidite sandstones from the Marine Regressive Megasequence (Guardado et al. 1990), deposited in bathyal settings controlled by halokinetic-generated depocenters and grabens (Figure 3). The main oil zones of the Barracuda field are the Oligocene reservoir with 1,500 MMBOE (55% of the original oil-inplace) and the lowermost Middle Eocene reservoir with 830 MMBOE (31% of the 001P).

Revista Brasileira de GeociênciasMonica R. : 63-79, junho de 2008 Arquivo digital disponível on-line no site www.sbgeo.org.br 63 Os processos de licitação de áreas exploratórias e áreas inativas com acumulações marginais no Brasil Resumo Em conseqüência da mudança no ambiente regulatório da indústria de petróleo e gás natural no Brasil foram realizadas nove rodadas de licitações de áreas exploratórias e duas rodadas para licitar áreas inativas com acumulações marginais. O modelo de licitação pública adotado pela agência reguladora para conceder às companhias de petróleo os direitos de lavra das referidas áreas baseia-se em leilões competitivos selados pela primeira maior oferta. De acordo com os conceitos da teoria dos leilões, o presente trabalho objetiva analisar os requisitos para adquirir os direitos de exploração e produção comercial e as variáveis de ofertas como bônus e obrigações mínimas para avaliação do potencial de produção de hidrocarbonetos. Este trabalho discute também os resultados dos leilões de áreas inativas e exploratórias em termos de competitividade, revelação de informação e analisa alguns impactos desses resultados no cenário brasileiro de petróleo. Observa-se que, mesmo com algumas diferenças nas regras do processo licitatório, os onze leilões da ANP obtiveram sucesso e possibilitaram a criação de um ambiente competitivo no setor de exploração e produção no Brasil. Esse sucesso pode ser traduzido em parte pela participação de 71 empresas nacionais e internacionais, algumas delas já atuantes em outros segmentos da indústria do petróleo, e outras formadas a partir da flexibilização do monopólio exercido pela PETROBRAS e a criação de novas oportunidades para exploração e produção de petróleo.Palavras-chave: Exploração de petróleo, leilão, oportunidades geológicas no Brasil.Abstract The brazilian bidding process for licensing exploration and mature petroleum areas. According to the regulatory changes in Brazilian oil and gas industry, nine leasing sales for exploration areas and two licensing rounds for inactive areas with marginal oil pools were promoted since 1997. The licensing model elected by the regulatory agency to concede petroleum exploration rights for these areas is a competitive firstprice sealed bid auction. This paper uses auction theory concepts to analyze rules, requirements for participation and acquisition, biddable factors such as signature bonus and minimum commitments for hydrocarbon potential production evaluation. This paper presents the results obtained with both exploration and inactive areas leasing systems, regarding competitiveness, information disclosure and analyze some impacts of these results in the Brazilian petroleum scenario. Besides the differences on the auction rules, the eleven licensing rounds promoted by ANP were a successful initiative by creating a competitive environment on the Brazilian exploration and production industry with more than 60 national and international companies and the creation of the new prospects for E&P activity in Brazil.

Petroleum auctions in US-GOM and Brazil are a common value first-price sealed bid, with fundamental differences on bidding systems defined by the regulators regarding the winner proposal. The US-GOM bidding model for offshore exploration areas considers the higher bonuses values as the winner offer. In Brazil, two main variables define the winner: the signature bonus and the minimum exploration program (PEM). The PEM aggregates value to the government, as it is a firm commitment to acquire geological data on the first exploration years. The amount of PEM committed reflects the importance of the exploration area for the bidders. This information not necessarily could be addressed by the simple high bids' analyses as in the US-GOM system. The Brazilian bidding model allows the bidders to a "full risk assessment" on their competitor's bidding behavior. This paper compares the risk perceptions of oil companies using the US-GOM and Brazilian bidding results for years 2005 and 2006, assuming the same oil price scenario and areas of similar geological settings. Another contribution of this paper is to present a competition model for evaluate different risk perceptions by using measures such as cash bonus (upfront money) and PEM (a long-term disbursement) generated by diverse bidding schemes. Preliminary results show that Brazilian high bids are in the same range of US-GOM bonuses (20,000.00 to 30,000.00 US$/km 2 ). Nevertheless, considering bonus and PEM as the winner offer, Brazilian high bids double the American ones. The competition model used for evaluate the firm performance in both bidding systems indicates that the utilization of bonus and PEM allow companies' decision makers to perform a better portfolio management, but demands the inclusion of a solid risk perception to select the best areas for bidding.