Following speculation in the French press, Tullow Oil plc (Tullow) announces that the Zaedyus-2 appraisal well (GM-ES-2), offshore French Guiana, has completed drilling. The well, drilled 5km up-dip from the Zaedyus-1 well, encountered a total of 85 metres of reservoir quality sands with oil shows in several objectives but did not encounter commercial hydrocarbons at this location.

Results of drilling, logging and sampling to date have shown that the reservoirs at this location are not in communication with Zaedyus-1. Integration of information obtained from the two wells with the 3D seismic data suggests the reservoirs are geologically separated from Zaedyus-1.

As Zaedyus-2 is up-dip and disconnected from Zaedyus-1, this result has no bearing on the bulk of the undrilled prospectivity which is located downdip of Zaedyus-1. Future drilling on the Zaedyus fan system should therefore target the significant upside in the Zaedyus down-dip prospects and the down-dip elements of Zaedyus Deep.

The Zaedyus-2 well was drilled in the Guyane Maritime licence using the Stena DrillMax Dynamically Positioned Drillship. The well was drilled in water depths of 1,894 metres and has been drilled to a depth of 6,200 metres and logging operations are ongoing. The second well in this four-well programme is Priodontes-1, targeting an adjacent prospect within the same Cingulata fan system, and is expected to commence drilling in early December.

Tullow has a 27.5% stake in the Guyane Maritime licence and is partnered by Shell, who are operator and hold a 45% stake, Total (25%) and Northpet (2.5%), a company owned 50% by Northern Petroleum plc and 50% by Wessex Exploration plc.

Angus McCoss, Exploration Director, commented today:
“While the Zaedyus-2 well has not proved an up-dip extension of the Zaedyus discovery towards the apex of the fan, the well has provided very valuable data for the exploration and appraisal strategy of the Cingulata fan system going forward. The French Guiana block remains highly prospective, particularly down-dip and still offer excellent potential for multiple exploration successes. These early lessons learned by the joint venture are being incorporated into our ongoing well campaign.”