Tullow Oil has confirmed yet another major oil discovery offshore Ghana, with its Owo-1 exploration sidetrack in the Deepwater Tano block which “significantly extended” the column of high-quality light oil discovered by the initial drill.
Pressure data indicates that the additional oil located “is in communication” with the reservoirs penetrated in the Owo-1 well, and confirms at least 69m (226ft) of total net oil pay in a substantial gross oil column of 200m (656ft).
But there’s more, as beneath the Owo oil reservoir a further 13m (42.5ft) of net condensate (volatile hydrocarbon liquids) pay has also been located, plus an additional six metres of net gas pay logged in the deepest sand encountered.
Importantly, no water was encountered in any of the hydrocarbon bearing reservoirs in either well, which suggests that further upside is in prospect.
Tullow said that following completion of logging operations the well will be suspended for future use in appraisal and development.
The Sedco 702 semi-submersible rig drilled the Owo-1 sidetrack to a total depth of 3,998m (13,117ft).
On completion of operations, the rig will remain in the Deepwater Tano block to drill the Onyina-1 exploration well which is targeting a large Campanian prospect between Tweneboa and the neighbouring Jubilee field, which is now in the late stage of development and is due onstream late this year.
Angus McCoss, Tullow’s exploration director, said: “Appraisal wells are currently being planned to extend the main Owo oil discovery up-dip and down-dip, to appraise the adjacent Tweneboa oil and gas condensate accumulation and, to refine further our estimates of recoverable resources of both fields.
“The discovery of very material volumes of light oil in Owo and the fact that the oil is concentrated in high-quality channel sands greatly enhances our outlook for the efficient future development of both the Owo and Tweneboa Fields.”