Petrobras’ 4-SPS-86B exploration well, drilled in the ultradeepwaters of Santos basin Block BM-S-8, has discovered a 471-m presalt column of 31 °API oil. The pay started at a depth of 5742 m, and consisted of carbonate reservoirs with excellent porosity and permeability. The well could not reach its planned total depth of 7000 m due to operational reasons and will be temporarily abandoned until future operations are planned. Petrobras (66%) is operator with partners Petrogal Brasil (14%), Barra Energia do Brasil Petróleo e Gás (10%), and Queiroz Galvão Exploração e Produção (10%).