Unconstrained, the combined rate has the potential to flow at around 5,200 bopd. In Uganda, the Ondyek-1 exploration well did not encounter hydrocarbons.
Twiga South-1 flow test – Kenya
The testing program at the Twiga South-1 oil discovery has now been successfully completed with a cumulative flow rate of 2,812 bopd, constrained by surface equipment. Tullow previously stated that Drill Stem Tests (“DST”) 3 and 4A flowed at a cumulative rate of 2,351 bopd and can now announce that the fifth and final DST flowed at a rate of 461 bopd. With optimised equipment these flow rates would increase to a cumulative rate of around 5,200 bopd. 37 degree API waxy sweet crude was flowed from all three zones in the Auwerwer formation with good quality reservoir sands encountered and the well has been suspended as a potential future production well. As with DST 4A, a Progressive Cavity Pump (PCP) was used to artificially lift at DST 5, whilst DST 3 flowed naturally. Two additional zones were tested in the tight reservoir rock at the base of the well and, as anticipated, both produced at sub-commercial rates but confirmed the presence of movable oil.
These results provide encouragement for the forthcoming testing program at Ngamia-1A, Block 10BB, where four zones are planned to be tested using the Weatherford 804 rig. Testing activities are expected to commence in March and complete by the end of May.
Tullow has a 50% operated interest in the Twiga South-1 well, Block 13T, with Africa Oil holding the remaining 50% interest.
Ondyek-1 exploration well – Uganda
Exploration drilling has continued in the Total operated EA-1A block to the north of Lake Albert with the Ondyek-1 exploration well, located 16km North West of the Nigiri-1 oil discovery. The well, designed to test the boundary limits of the EA-1A Block, was drilled to a total depth of 1,462 metres. The well did not encounter hydrocarbons and has been plugged and abandoned. Further evaluation is being carried out on the Lyec-1 discovery and partners are re-evaluating the remaining exploration potential of the area in light of recent well results.
Tullow has a 33.33% non-operated interest in EA-1A with Total (operator) and CNOOC each holding a 33.33% interest.
Angus McCoss, Exploration Director of Tullow Oil plc, commented today,
“While it is still early days for our exploration campaign in Kenya, these flow tests results at Twiga South-1 are an important step on the way towards understanding the commercial potential of the two discoveries we have made so far. The Ondyek-1 well in Uganda did not encounter hydrocarbons but has contributed much to our understanding of the limits of the EA-1A block.”