Kosmos Energy said Wednesday that its Guembeul-1 exploration well has made a significant gas discovery at the St. Louis Offshore Profond license area in offshore Senegal.
The well encountered 331 feet of net gas pay in “two excellent quality reservoirs,” including 184 feet in the Lower Cenomanian and 148 feet in the underlying Albian, with no water encountered.
Guembeul-1 demonstrated reservoir continuity as well as static pressure communication with the Tortue-1 well in the Lower Cenomanian, suggesting a single, large gas accumulation.
Dallas-based Kosmos said the Guembeul-1 well has “significantly de-risked adjacent prospectivity,” including proving the existence of “excellent quality reservoirs” in the Albian.
The well has also provided additional calibration of the company’s seismic attribute exploration tool,”confirming its reservoir and fluid predicative capability for these primary exploration targets,” Kosmos added.
Based on the integration of the Guembeul-1 well results, the company’s Pmean gross resource estimate for the Tortue West structure has increased to 11 trillion cubic feet from 8 Tcf thanks to greater reservoir confidence in the Cenomanian and the inclusion of volumes in the Albian.
The Pmean gross resource estimate for the Greater Tortue Complex has increased to 17 Tcf from 14 Tcf.
The Guembeul-1 well was drilled to a total depth of 17,208 feet in 8,858 feet of water, about 3 miles south of the basin-opening Tortue-1 gas discovery that has been renamed Ahmeyim.
Kosmos added that it entered into a memorandum of understanding with Senegal’s Pétroles du Sénégal (Petrosen) and Mauritania’s Société Mauritanienne Des Hydrocarbures et de Patrimoine Minier (SMHPM) that sets out the principles for an intergovernmental cooperation agreement for the development of the cross-border Greater Tortue resource.
The MOU enables Kosmos and the two governments to work together toward early development of the field, Kosmos said.
“We are pleased to have delivered another major discovery with our first exploration well offshore Senegal. Guembeul-1 confirms the presence of a world class gas resource that extends into both Senegal and Mauritania. With our successful appraisal program and support of both governments, the initial gas development is gaining momentum,” Kosmos chairman and CEO Andrew G. Inglis said.
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.
The delineation well will test the downdip limits of the field and is expected to complete the appraisal of the Tortue West structure.
Kosmos holds a 60 percent interest in the Guembeul-1 well.
Timis Corporation Limited holds a 30 percent and Petrosen holds a 10 percent stake.
Since 2014, Kosmos has held rights to conduct exploration in the St. Louis Offshore Profond and Cayar Offshore Profond license areas under production sharing contracts with the government of Senegal.