BG Group (25%) and partners Petrobras (65% and operator) and GALP (10%) have completed two drill stem tests (DSTs) on the Iracema well (4-RJS-647 or 4-BRSA-711-RJS) in the BM-S-11 appraisal area in the Santos Basin pre-salt, offshore Brazil.

DSTs were carried out over two zones with aggregate production amounting to 10 500 barrels oil per day of light 32° API oil and 17 million standard cubic feet per day (mmscfd) of gas. Flow rates were facilities constrained.

The Iracema appraisal well has confirmed the presence of an excellent quality light oil bearing reservoir, 33 kilometres north-west of the original Tupi discovery well (1-RJS-628A or 1-BRSA-369A).

The well in-flow performance recorded during the tests was the highest so far achieved in BG Group's Santos Basin interests. Ultimately, development well flow rates of up to 50 000 barrels oil equivalent per day (boepd) are anticipated; these rates being constrained by production facilities rather than reservoir performance.

The excellent characteristics of the pre-salt carbonate reservoirs in BG Group's concessions, confirmed by recent appraisal wells, have a highly significant positive influence on expected well recoveries, well density, development capital expenditure and project economics.

BG Group Chief Executive Frank Chapman said "We are delighted with the results of this latest appraisal well, situated 33 kilometres from the initial Tupi well. This provides further evidence of the very large areal extent and prolific nature of the pre-salt discoveries we have made. We will be working closely with our partners to consider the optimum Tupi and Iracema development sequence, following this outstanding result."

Further evaluation of the well data is on-going and work on field development options has been initiated. BG Group and its partners will continue the activities and investments foreseen in the Evaluation Plan approved by the Brazilian National Petroleum Agency (ANP), including the drilling of further wells in the area.

Iracema, in the BM-S-11 appraisal area, was drilled to a depth of 5 000 metres and completed in September 2009. It is located in 2 210 metres water depth, around 250 kilometres off the coast of the State of Rio de Janeiro.