Petrobras augments oil arsenal as it strikes black gold in Brazilian waters

March 26, 2026, by Melisa Cavcic

Brazilian state-owned energy giant Petrobras has made a new oil discovery in the pre-salt of the Campos Basin off the coast of Brazil.

Petrobras has announced the presence of excellent-quality oil in the pre-salt Campos Basin through an exploration well drilled in the Marlim Sul field, which was discovered in November 1987 through the well 4-RJS-382.

The Brazilian giant is the operator of the field with a 100% working interest. The well 3-BRSA-1397-RJS is located 113 kilometers off the coast, in the municipality of Campos dos Goytacazes (RJ), in 1,178 meters of water depth.

The oil-bearing interval was identified based on wireline logs, hydrocarbon shows (gas indications), and fluid sampling. According to the firm, the drilling operations were completed safely, in compliance with HSE requirements and with respect for the environment and people.

Map indicates the discovery location in the Campos Basin; Source: Petrobras

The Brazilian giant explains that samples will be sent for laboratory analyses to characterize the reservoirs and fluids encountered, supporting the continued appraisal of the area’s potential.

Petrobras’ activities in the Campos Basin are aimed at replenishing oil reserves in the mature producing basin, ensuring the company’s sustainability and meeting the country’s energy demand during the energy diversification period.

This discovery comes only days after the firm revealed a new gas discovery off the coast of Colombia.