LONDON -- Dana Petroleum has discovered a new oil field with its well at the South East Rinnes structure in block 210/24a in the UK Northern North Sea. This is the third oil field discovered by Dana in the Rinnes area and is located 4 km (2.5 mi) from the company's operated Hudson producing oil field and 1 km (0.6 mi) from its Melville oil field.
The South East Rinnes well, 210/24a-12, was drilled to TD of 7,310 ft (2,228 m). A comprehensive set of wireline log data was acquired including pressure measurements and oil samples. The well targeted the Lower Brent reservoir in a separate, untested structure between the Melville and East Rinnes oil fields.
The well found excellent quality sands within the Lower Brent sequence with a full oil column throughout the Brent reservoir and no oil-water contact, the company reports.
Dana decided to sidetrack the well downdip to the north to explore deeper on the structure for the oil-water contact. The sidetrack well 210/24a-12z, was drilled to TD of 8,040 ft (2,451 m) and encountered the Lower Brent reservoir sequence much deeper than in the initial discovery well. A set of electric wireline logs also was acquired in the sidetrack. The data from the sidetrack well confirmed a total oil column of over 400 ft (122 m) true vertical thickness in South East Rinnes field, the company says
In addition, Dana has concluded an exploration well on the shallower South West Rinnes structure, a more speculative target southwest of 210/24a-12. Well 210/24a-13 was drilled to TD of 5,095 ft (1,553 m) and encountered excellent quality Brent reservoir, but the reservoir was water-bearing at this location, the company says.
The company will now integrate all the log, pressure and fluid data collected from both exploration wells and the South East Rinnes sidetrack. Dana's technical team will interpret the newly reprocessed 3D seismic dataset for this area, using the new well information, and then remap the West Rinnes, East Rinnes, South East Rinnes, and Melville oil fields to determine the total volumes of oil discovered in this area. At this time, prior to the remapping work, it is estimated that the Rinnes – Melville – Hudson area contains between 55 and 100 MMbbl of oil reserves yet to be produced, with a current most likely (P50) estimate of 80 MMbbl of oil.
Engineering studies have already begun to evaluate the potential development scenarios for the project. These include tie-back options to nearby existing infrastructure as well as stand-alone development via an FPSO vessel.