Exxon Mobil announces significant oil discovery offshore Guyana Exxon Mobil announced a significant oil discovery on the Stabroek Block, located approximately 120 miles offshore Guyana. The well was drilled by ExxonMobil affiliate, Esso Exploration and Production Guyana Ltd., and encountered more than 295 feet of high-quality oil-bearing sandstone reservoirs. It was safely drilled to 17,825 feet in 5,719 feet of water. Stabroek Block is 6.6M acres. The well was spud on March 5. The well data will be analyzed in the coming months to better determine the full resource potential. Esso Exploration and Production Guyana Ltd. holds 45% interest. Hess Guyana Exploration Limited holds 30% interest and CNOOC Nexen Petroleum Guyana Limited holds 25% interest.