Kosmos Energy has made a major gas discovery off the coast of Senegal at Yakaar-1 well located in the Cayar Offshore Profond block.
The first well in a series of four independent tests of the basin floor fan fairways, Yakaar-1 has intersected a gross hydrocarbon column of 120m in three pools within the primary lower Cenomanian objective and encountered 45m of net pay.
The well is situated nearly 95km north-west of Dakar at 2,550m water depth and has been drilled to a total depth of approximately 4,700m.
Preliminary results confirmed the presence of thick, stacked, reservoir sands across a large area with high porosity and permeability.
Kosmos Energy chairman and CEO Andrew Inglis said: “Kosmos has a 100% success rate in the basin with six consecutive successful exploration and appraisal wells drilled to date, confirming that our geologic model and geophysical tools are well calibrated.
“The result also confirms our view of the potential scale of the petroleum system offshore Mauritania and Senegal, in particular, the basin floor fan systems, which have now been further derisked, with the well demonstrating that reservoir and trap both work in these previously untested fairways.”
The company estimates that the discovered resource contains approximately 15 trillion cubic feet of gross mean gas complying with the pre-drill expectations.
Preliminary analysis of gas samples suggest that the well encountered a gas with a condensate-to-gas ratio (CGR) in the range previously encountered at Tortue and Teranga, approximately 15-30 barrels per million standard cubic feet.
Kosmos has planned an appraisal programme to delineate the Yakaar discovery.
Following completion of the Yakaar-1 well operations, the drillship Atwood Achiever will be mobilised to the Tortue-1 well to carry out a drill stem test on the Tortue discovery. This will further allow to perform front-end engineering design in the second half of this year.
The final investment decision and first gas are expected in 2018 and 2021 respectively.