Kosmos Energy Ltd.’s first attempt to delineate the Greater Tortue area offshore Senegal encountered 101 m of net natural gas pay in two reservoirs in the northern part of the St. Louis Offshore Profond license area (OGJ Online, Nov. 12, 2015), the company said.

The Guembeul-1 exploration well was drilled 5 km south of the basin-opening Tortue-1 gas discovery (renamed Ahmeyim)(OGJ Online, Apr. 27, 2015). The well was drilled in 2,700 m of water to a total depth of 5,245 m, encountering 56 m of pay in the Lower Cenomanian and 45 m in the underlying Albain. Neither interval contained water, Kosmos reported, adding the well demonstrated reservoir continuity as well as static pressure communication with the Totue-1 well in the Lower Cenomanian. This suggests a single, large gas accumulation.

Based on the results from Guembeul-1, Kosmos increased its gross resource estimate for the Tortue West structure to 11 tcf from 8 tcf. For the Greater Tortue Complex, estimates have increased to 17 tcf from 14 tcf.

The Atwood Achiever drillship will now proceed to Mauritania to drill the Ahmeyim-2 delineation well in the southern part of Mauritania’s Block C-8.

Kosmos holds a 60% interest in the Guembeul-1 well. Partners include Timis Corp. Ltd. 30% and Petrosen 10%.