ExxonMobil unit makes non-commercial discovery offshore Guyana

ExxonMobil and Kaieteur block partners will evaluate data from a discovery offshore Guyana currently considered non-commercial as a stand-alone development, partner Ratio Petroleum Energy LP said Nov. 17. The 13,535-sq km block lies 250 km offshore in water depth of 2,800-3,800 m.

Tanager-1 well—the deepest drilled in Guyana-Suriname basin to date—was spudded Aug. 11 by the Stena Carron drillship, and reached 7,633 m TD (OGJ Online, Aug. 13, 2020). Evaluation of LWD, wireline logging, and sampling data confirm 16 m net oil pay in high-quality sandstone reservoirs of Maastrichtian age. Preliminary evaluation of fluid samples from the Maastrichtian reservoir indicates heavier oil than is reported from Liza Phase I producing field crude assays. The samples will be analyzed over the coming months.

Although high quality reservoirs were also encountered at deeper Santonian and Turonian intervals, interpretation of reservoir fluids is reported to be equivocal at this stage and requires further analysis. The well will be plugged.

Tanager-1 results confirm continuance of a Cretaceous petroleum system and the Liza play fairway onto Kaieteur block, down dip from the prolific discoveries on neighboring ExxonMobil-operated Stabroek block. Kaieteur partners will evaluate data collected at Tanager-1 with a view to understanding the well result, recalibrating the seismic model for the basin segment, and high grading the next potential drilling targets on the block. A prospect inventory has been mapped across the 5,750 sq km 3D seismic survey, which was acquired in the southern part of the block in 2017.

Esso Production & Exploration Guyana Ltd., an ExxonMobil subsidiary, is operator of the block with 35% interest. Pastners are Cataleya Energy Ltd. (25%), Ratio Guyana Ltd. (25%), and Hess (15%).