Etame 8-H was drilled to 3,196 m (10,485 ft) MD, penetrating the Gamba Sand reservoir interval at 1,820 m (5,971 ft) TVD, and contacting 135 m (443 ft) of good-quality reservoir within the oil-bearing portion. Additionally, the wellbore encountered the current oil/water contact at 1,829 m (6,000 ft) TVD, with a 9-m (29-ft) vertical oil column.
However, the well was subsequently shut in due to production of hydrogen sulfide (H2S) during the initial testing process. Investigations are in progress to determine the root cause and how this may affect the development.
Transocean Constellation II has since relocated to drill the Etame 10-H development well, targeting the Gamba sand formation in the 1-V fault block in the Etame field, where Vaalco has been producing oil since 2002 via subsea wells. Operations to date in the fault block, south of the main Etame reservoir, have not encountered H2S.
Following the recent results the planned third well (Etame 9-H) in the Etame platform campaign, located in the same fault block as Etame 8-H, will be re-evaluated.
The company has started to design a crude sweetening facility to allow redevelopment of the Ebouri field and to provide sweetening capacity for future wells producing H2S. The previously targeted commissioning date was 2017, but this may be brought forward after the discovery of H2S at Etame 8-H.
Once Etame 10-H is completed, the rig will mobilize to drill three additional development wells from the Southeast Etame/North Tchibala, “SEENT” platform, starting with a well into the Gamba formation in the Southeast Etame field, followed by two wells drilled from the platform into the Dentale sand formations in the North Tchibala field.