Tullow Oil PLC and Africa Oil Corp. have tested a cumulative 2,351 b/d ofoil from two shallow sands at the Twiga South-1 discovery well on Block 13T in northwestern Kenya, the country’s “first potentially commercial flow rates achieved in Kenya.”
Four flow tests have been carried out at Twiga South-1 in January and early February and a fifth test is in progress. A cumulative rate of 2,351 b/d was recorded from two sands in the Auwerwer formation, Africa Oil said.
One sand flowed at a maximum 1,860 b/d of 37°gravity oil, and the other made 491 b/d on a progressive cavity pump. Africa Oil expects a final rate of more than 500 b/d on PCP on the final Auwerwer test in progress.
Two deeper tests were also completed on the tight reservoir rock at the bottom of the well and, as anticipated, both produced at subcommercial flow rates and reconfirmed the presence of movable oil, Africa Oil said (OGJ Online, Nov. 26, 2012).
The company said the reservoir quality of the Auwerwer sands appears to be significantly better than predicted, which was also supported by recent core analysis data with several values over 1 darcy permeability. The tests provide real encouragement for the forthcoming DST program at the Ngamia discovery 22 km south of Twiga South-1.
With conclusion of the Twiga South-1 test program, the Weatherford-804 rig will move to reenter Ngamia-1A to perform at least four flow tests.
Meanwhile, the Paipai-1 well has reached a total depth of 4,255 m, encountering igneous rocks at the base that appear to be basement. Light hydrocarbon shows were encountered in sands in the Lower Cretaceous interval, and the well is being cased for additional fluid sampling by MDT. Further testing or evaluation of Paipai, if warranted, would follow with a dedicated test unit.
On completion of operations at Paipai, the Sakson PR-5 will mobilize to Kenya Block 10BB to spud the Etuko-1 well in the Lokichar basin in the second quarter of 2013.
Africa Oil said it will focus on the shallow Auwerwer section as the primary reservoir in the upcoming exploratory program on the western flank of the Lokichar basin.
“We remain intrigued by the lower fractured reservoir and Lower Lokhone sands which will be further evaluated in future exploration,” the company said. “Our aggressive 2013 drilling program includes numerous high impact wells on trend with the Lokichar discoveries but also wells in new areas designed to open additional subbasins in our large acreage portfolio.”ex
