By Toyin Akinosho, Publisher
The first appraisal of the Ngamia discovery onshore Kenya encountered much less hydrocarbon footage than the first well.
Ngamia-2, drilled 1.6 kilometres from the basin opening Ngamia-1 discovery well, found 39 metres of net oil pay and 11 metres of net gas pay. Combined, the 50 metres footage is about half the over 100metres of net oil pay that was announced after the finalization of the Ngamia-1 sidetrack in June 2012.
This time, Tullow Oil and partner African Oil chose to describe the Ngamia-2 pay counting feet, rather than in metres. Their press releases announced “128 feet of net oil pay and 36 feet of net gas pay”, contrary to “more than 100metres of net oil pay” announced two years ago, in the course of reporting the results of Ngamia-1 operations. (100 metres = 328 feet).
The good news here, though, is that “the well also appears to have identified a new fault block trap north of the main Ngamia accumulation”, the partners said, noting note that “the reservoirs were high quality with more than 655 feet of net reservoir sands, with good permeability inferred from sampling”. It’s important to clarify that the “655 feet of net reservoirs” are not charged with hydrocarbons at the Ngaima-2 well location.
It is the testing of the Ngamia-2 well, expected later, that will offer the clearer insight. It looks like the partners will test Ngamia-2 only after more wells have been drilled on the structure.“The rig used to drill the well will now drill up to four more wells in the Ngamia field for an extended well test programme”, the partners said. (Ngamia-1 tested, in July 2013, cumulative flow rate of 3,200 barrels of oil per day (BOPD)from six Drill Stem Tests (DST’s). There’s also going to be more geoscience work to understand the play. “A 3D seismic data acquisition program is currently being concluded over the field area, which should allow for detailed mapping of the fault trends”.
