Report of discoveries in Brazilian pre-salt - Part 16
Report of ten selected discoveries in Brazilian pre-salt - Part 16 (Prospects - Florim - Prospective Resources)
by F. Busquet
The area of the Florim prospect is part of the Transfer of Rights Agreement to explore and produce oil, natural gas and other fluid hydrocarbons in certain blocks of the pre-salt area, up to the limit of 5 bn barrels of oil equivalent, as provided under Law No. 12, 276 signed by the President of Brazil on June 30, 2010 (“Law No. 12,276”), including the initial purchase price of the transfer of rights, to be entered into among Petrobras, as assignee, the Brazilian federal government, as assignor, and the National Petroleum, Natural Gas and Biofuels Agency – ANP, as regulator (the “Assignment Agreement”).
The Board of Executive Officers authorized all necessary actions to conclude the transfer of rights, including the execution of the Assignment Agreement, according to news published by Petrobras in September 1, 2010.
- The Florim prospect is located in water depths of approximately 2,000 m about 300 km south of Rio de Janeiro in open acreage and less than 10 km north of the Iara discovery.
- Iara was discovered in September 2008 by the exploration well 1-BRSA-618-RJS which found the Cretaceous pre-salt interval (Sag and Upper Syn-Rift) oil-bearing.
6.2 Geological Model
- The expected reservoir section in Florim includes microbial and stromatolitic carbonates of the Sag Sequence and underlying limestone coquinas of the late Syn-Rift Sequence.
- Depth structure mapping of the Florim prospect is based on 3D PSDM seismic data. A combination of generally poorer seismic data quality and greater structural complexity makes the Base Salt interpretation at Florim less reliable than other prospects and discoveries in the area.
- The seismic mapping, in particular the top reservoir / Base Salt horizon, was reviewed by GCA and found to be less reliable than other prospects and discoveries in this area.
- Florim is a north-south elongate feature, dip-closed with a northern and southern culmination separated by a saddle. The saddle is within spill closure (31 sq km), but is overlain by a relatively thin salt section, which adds seal risk.
6.3 Estimation of Oil-in-Place
- The GRV range is based upon GCA’s review of the seismic data available and derived from the ANP’s Petrel model.
- Based on the well log data made available by the ANP and in consideration of other analogous discoveries and prospects, plus a limited amount of regional well data, GCA considers that the mean formation evaluation input parameters for volumetric estimation are as follows: porosity 10 %, oil saturation 76 %, N/G 57 %
- Standard deviation for the porosity and oil saturation, standard error of the mean for N/G and their bases are specified for each discovery and prospect in the Formation Evaluation in Appendix V.
- Based on the PVT data provided, GCA considers that a reasonable range of FVF is 1.43 stb/rb and 1.58 stb/rb, and the GOR lies between 1,035 cf/bbl and 1,265 cf/bbl.
- OOIP for Florim range from a Low Estimate of 0.2 bn bbl to a High Estimate of 0.7 bn bbl with a Best Estimate of 0.4 bn bbl.
6.4 Resource Estimate
- The estimated recovery factor, considering a depletion and water injection production system, is estimated to be between 8 % and 34 %, with a most likely value of 18 % for the 27° API oil.
- Rounded Prospective Resources (bn bbl) for the Florim prospect are estimated as follows:
Table 16: Rounded Prospective Resources (bn bbl)
6.5 Development Plan and Economic Analysis
- Given the small size of this prospect, only 2 production and 2 injection wells will be needed to recover the Best Estimate resource of 65 mm bbl, producing at initial rates of 10,000 boepd/well. The wells will be tied-back to one of the Iara FPSOs using no more than 15 % of its 100,000 boepd capacity.
- The unrisked NPV 10 for the Best Estimate resource success case is $ 438 mm equivalent to $ 6.74/bbl.
Figure 36. Florim Prospect Location Map
Figure 37. Florim Prospect Map (Base Salt Depth)