State-owned company said it had identified “excellent quality” material in a well in the Marlim Sul field, 113 km from Campos de Goytacazes
A announced this Thursday (26th March 2026) the discovery of oil in the Marlim Sul field, in the pre-salt of the Campos Basin, on the north coast of Rio de Janeiro.
The state-owned company said it had found oil “excellent quality” in the exploratory well 3-BRSA-1397-RJS, located 113 km off the coast of Campos dos Goytacazes (RJ), at a depth of 1,178 meters.
“The samples will later be sent for laboratory analysis, which will allow the conditions of the reservoirs and fluids found to be characterized, enabling the continued assessment of the area’s potential”Petrobras said in a statement. The company has 100% interest in the operation of the field.
In November 2025, the state-owned the discovery of a high-quality oil reserve in the post-salt of the Sudoeste de Tartaruga Verde block, also in the Campos Basin, located 108 km off the coast of Campos dos Goytacazes. The reservoir is 734 meters deep in the sea.
The difference between pre-salt and post-salt is the geological location and depth in relation to the salt layer below the sea. The pre-salt is below this layer, being deeper (up to 7km from the surface) and older in formation, while the post-salt is above the salt and is shallower.
Since its discovery in 2006, the pre-salt has been responsible for transforming Brazil into one of the largest global oil producers.
Read the full Petrobras note:
“Petrobras identified the presence of excellent quality oil in the pre-salt Campos Basin, in an exploratory well drilled in the Marlim Sul field. Well 3-BRSA-1397-RJS is located 113 km from the coast in the city of Campos dos Goytacazes-RJ, at a water depth of 1,178 meters.
The oil-bearing interval was verified through electrical profiles, gas signs and fluid sampling. The samples will later be sent for laboratory analysis, which will allow the conditions of the reservoirs and fluids found to be characterized, enabling the continued assessment of the area’s potential. The well drilling was completed safely, respecting the environment and people.
Petrobras’ operations in the Campos Basin aim to restore oil reserves in mature areas, ensuring the company’s sustainability and meeting national energy demand, during the period of energy diversification.
The Marlim Sul field was discovered in November 1987 through well 4-RJS-382. Petrobras is the operator of the field with 100% interest.”
