ExxonMobil is working to identify the best prospects on prime exploration acreage offshore Guyana, with the clock ticking for the US supermajor to relinquish part of its concessions back to a government that is impatient to offer the acreage back to the market or obtain better terms.

ExxonMobil has so far discovered about 10 billion barrels of oil equivalent in recoverable resources at the prolific Stabroek block, but it is not enjoying similar success at the adjacent Canje and Kaieteur concessions, located in deeper waters.