Oil encountered deeper in Tweneboa-1 exploration well (Tullow 49.95%)
On behalf of the Deepwater Tano licence partners, Tullow announces that following the significant light hydrocarbon discovery reported earlier this month, the Tweneboa-1 well has been deepened to 3,938 metres and encountered four metres of highly-pressured oil bearing sands as well as an over-pressured zone at total depth.
Results of wireline logs, pressure measurements and sampling show that the well has encountered oil of 26 degrees API which is independent of the shallower light hydrocarbon accumulation. Near the total depth of the well, an over-pressured zone was encountered which limited further progress. Integration of the seismic and well data is ongoing and further exploration drilling will now be required to test the extent of these deeper levels as well as the shallower accumulation where seismic indicates sands thicken away from the well location.
The Tweneboa-1 well was drilled by the Eirik Raude deepwater rig in a water depth of 1,148 metres some 25 kilometres west of the Jubilee Field.
Tullow (49.95%) operates the Deepwater Tano licence and is partnered by Kosmos Energy (18%), Anadarko Petroleum (18%), Sabre Oil & Gas (4.05%) and the Ghana National Petroleum Corporation (GNPC) (10% carried interest).
Karuka-2 exploration well in uganda (Tullow 100%)
The Karuka-2 exploration well on the Vundu prospect in Block 2 Uganda has been drilled and logged. The well reached a total depth of 897 metres and encountered limited thin-bedded oil bearing sands from 764 metres to 772 metres.
Karuka-2 was located six kilometres south-west of the Karuka-1 well and was a higher risk well designed to test upside potential in the secondary Escarpment Play. Downhole pressure testing and sampling indicate moveable waxy crude in reservoir close to a possible oil-water contact however the upside potential in the structure is limited.
The Karuka-2 well is being suspended and the rig will then move to drill the amplitude supported Nsoga prospect in the Victoria Nile Delta play which is expected to spud in early April.
In addition, the Nabors 221 rig is fully rigged up on the shore of Lake Albert and is expected to commence drilling the Ngassa-2 exploration well imminently. Ngassa is the largest prospect in the basin and is expected to take up to 90 days to drill.
Commenting today, Angus McCoss, Exploration Director, said:
“Tweneboa is a significant light hydrocarbon discovery which has extended the Jubilee play westwards and has identified oil in a deeper sand pointing to scope for further play development. We look forward to exploring these multiple targets offshore Ghana and pursuing these plays across the rest of our extensive Equatorial Atlantic acreage position.
The Karuka-2 well has confirmed our existing understanding of the Escarpment play. For the remainder of 2009 our Butiaba programme will focus on the prolific Victoria Nile Delta play and look to replicate and extend the successful reservoir cascades encountered during our 2008 drilling programme.”