Kosmos Energy has announced today that the Tortue-1 exploration well, in Block C-8 offshore Mauritania, has made a significant, play-opening gas discovery.
Based on the preliminary analysis of drilling results and intermediate logging to a depth of 4,630 meters, Tortue-1 has intersected 107 meters (351 feet) of net hydrocarbon pay. A single gas pool was encountered in the primary Lower Cenomanian objective.
The Lower Cenomanian is comprised of three excellent quality multi-Darcy reservoirs totaling 88 meters (288 feet) in thickness over a gross hydrocarbon bearing interval of 160 meters (528 feet). A fourth zone 19 meters (62 feet) thick was penetrated within the secondary Upper Cenomanian target over a gross hydrocarbon bearing interval of 150 meters (492 feet).
Andrew G. Inglis, chairman and chief executive officer, said: “Volumetrically, the Tortue-1 well has far exceeded our pre-drill expectations and has discovered a large scale gas resource. Our seismic imaging indicates the areal extent of Tortue West could cover approximately 90 square kilometers that will be better defined with appraisal drilling. Importantly, given the results and excellent well-to-seismic calibration, the Tortue-1 well has significantly de-risked our large and under-explored 27,000 square kilometer deepwater position in Mauritania. Our acreage offers substantial follow-on prospectivity including a diverse range of Cenomanian as well as deeper Cretaceous plays and fairways with strong dependency.”
An appraisal program is being planned to delineate the Tortue West discovery. In addition, the Marsouin-1 exploration well, located in the central part of Block C-8, is expected to spud in the third quarter of 2015. An exploration program is also being formulated to test the other prospects in the Greater Tortue Complex, which extends into the St. Louis Offshore Profond Block in Senegal, including the Tortue East and Tortue North prospects. In support of this program, a 3D seismic survey acquired over ourSenegal blocks in 2014 is currently being processed and interpreted.
Brian F. Maxted, chief exploration officer, said: “This significant play-opening discovery validates our frontier exploration strategy where we are now one in three in our ‘Second Inning’ campaign. Our results demonstrate that our organic deepwater exploration business model, which targets early access to build large acreage positions with significant follow-on dependent prospectivity, can deliver significant value for our shareholders.”
Located approximately 285 kilometers southwest of Nouakchott in 2,700 meters of water, and drilled with the Atwood Achiever drillship, the Tortue-1 well is now drilling to the planned total depth of approximately 5,250 meters.
Kosmos currently owns a 90 percent interest in the Tortue Prospect, along with Société Mauritanienne Des Hydrocarbures et de Patrimoine Minier (SMHPM) at 10 percent. Since 2012, Kosmos has held rights to conduct exploration in the C-8, C-12 and C-13 contract areas under production sharing contracts with the Government of Mauritania.
In March 2015, Chevron Mauritania Exploration Limited, a wholly owned subsidiary of Chevron Corporation, acquired a 30% non-operated interest in the C-8, C-12 and C-13 contract areas under production sharing contracts. Chevron has an option to elect to participate at a 30% interest in the Tortue Prospect, subject to Chevron paying a disproportionate share of their costs related to the Tortue-1 exploration well. The blocks are contiguous, range in water depth between 1,000 and 3,000 meters, and have combined acreage of approximately 27,000 square kilometers.