Brazil’s state-controlled oil producer Petrobras has reported a subsalt oil discovery in the fourth well drilled in the Jupiter area in the Santos Basin pre-salt block BM-S-24.

The existence of a subsalt oil discovery in the 3-BRSA-1246-RJS well, also known as Apollonia well, confirms the extension of the Santos Basin pre-salt discovery, offshore Brazil.

The Apollonia well lies 296km offshore Rio de Janeiro, 8km south-west of the 1-RJS-652A discovery well, in 2,183m of water.

The well has proved the existence of a 313m hydrocarbon column, starting at a depth of 5,166m, with rocks showing good porosity and permeability conditions.

Drilling has also indicated an 87m thick oil column, and fluid samples collected in the well demonstrate similar characteristics to those found in the 1-RJS-652A wildcat well and two extension wells.

The extension wells drilled to date found a large deposit of natural gas and carbon dioxide, condensate, and oil.

Petrobras plans to continue drilling the Apollonia well until it reaches a total depth of 5,700m.

Petrobras is the operator of BM-S-24 with an 80% stake. Petrogal Brazil, owned by Protugal’s Galp Energia SGPS and China’s Sinopec, holds the remaining 20% interest.

The consortium will go ahead with the activities provided for in the Discovery Evaluation Plan approved by Brazil’s National Petroleum, Natural Gas and Biofuels Agency.

In July, Petrobras revealed that its average pre-salt output in May accounted for 22% of the total amount of oil produced by the company in Brazil.

Average daily production in the pre-salt reservoirs has increased ten-fold to 520,000 bpd from 2010 to this year.

Of the 25 wells operating in Brazil, ten are situated in the Santos Basin, accounting for 53% of pre-salt output at 274,000 bpd.

The rest of the 15 wells are located in the Campos Basin, accounting for the remaining 47% at 246,000 bpd.

Image: The Apollonia well, which is the fourth drilled in the Jupiter area, lies 296km offshore Rio de Janeiro. Photo: courtesy of Petrobras News Agency.

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