Harvest Natural Resources Reservoir Inc., Houston, will start conceptual engineering studies with the aim of evaluating the commerciality of the discovered oil in the Gamba and Dentale reservoirs at Tortue, the company’s previous Ruche oil discovery, and the nearby Walt Whitman and Moubenga oil discoveries offshore Gabon.
The Dussafu Tortue Marin-1 discovery, announced in January 2013 as a discovery, has been appraised with an 1,800-ft sidetrack to the southwest to test the lateral extent and structural elevation of the presalt Gamba and Dentale reservoirs.
The sidetrack found 65 ft of net oil pay in the primary Dentale reservoir with better reservoir character and an apparent similar fluid level to that encountered in the DTM-1 vertical well. It also encountered several other stacked sands with oil shows, but a stuck downhole tool caused early termination of logging before pressure data could be collected to confirm connectivity.
The Tortue oil discovery extends the proven fairway for stacked presalt reservoirs and has demonstrated the exploration potential of the seaward part of the Dussafu license, Harvest said. It will suspend the well pending future appraisal and development activities and release and demobilize the rig.
Harvest operates the Dussafu PSC, holding a 66.667% interest.