BG Group plc announced an extended well test (EWT) had increased the production potential of the Carioca discovery located on the BM-S-9 concession in the Santos Basin, offshore Brazil.

Results from the EWT in progress at the well 3-SPS-74, known as Carioca Nordeste, indicate potential production of approximately 28 000 barrels of oil per day (bopd), above initial expectations. The well, which is connected to the FPSO Dynamic Producer, is currently producing 23 400 bopd, constrained by facilities.

The potential of the Carioca area was further underlined by results from the
4-BRSA-973A-SPS well, informally known as Abaré, located 35 kilometres south of the discovery well 1-BRSA-491-SPS (Carioca) and 293 kilometres off the coast of São Paulo state.

Wireline samples showed good quality oil at Abaré, about 28° API, in carbonate reservoirs at a depth of about 4 830 metres. A drill stem formation test is planned to evaluate the productivity of the interval.

Five wells have now been drilled in the Carioca area in addition to the completion of two formation tests. This fulfills the evaluation commitments required by the National Agency for Petroleum, Natural Gas and Biofuels (ANP).

Given the promising results at Carioca, the consortium intends to do more appraisal work to further evaluate the area’s full potential.

To allow this, the ANP has approved a revision of activities and has extended the deadline for a Declaration of Commerciality from November 2011 to 31 December 2013. There is no change to the consortium’s plans and schedule for development and production.

BG Group has a 30% interest in Block BM-S-9 which is comprised of two appraisal areas – Guará and Carioca (Petrobras 45%, operator and Repsol Sinopec 25%).