ExxonMobil unit makes eighth oil discovery offshore Guyana

ExxonMobil Corp. affiliate Esso Exploration & Production Guyana Ltd. encountered 265 ft of high-quality, oil-bearing sandstone following the drilling of the Longtail-1 well offshore Guyana, creating potential for additional resource development in the southeast area of the Stabroek block.

The well was drilled to 18,057 ft in 6,365 ft of water. The oil discovery marks the eighth on the block for the company. Drilling by the Stena Carron drillship commenced on May 25.

The Longtail-1 well follows previous discoveries on the Stabroek Block at Pacora, Liza, Payara, Liza Deep, Snoek, Turbot, and Ranger (OGJ Online, May 20, 2015;Jan. 12, 2017;Mar. 30, 2017;Oct. 5, 2017;Jan. 5, 2018; and Feb. 28, 2018.)

“The Longtail discovery is in close proximity to the Turbot discovery southeast of the Liza field,” said Steve Greenlee, president of ExxonMobil Exploration Co. “Longtail drilling results are under evaluation. However, the combined estimated recoverable resources of Turbot and Longtail will exceed 500 million boe and will contribute to the evaluation of development options in this eastern portion of the block.”

The company plans to add a second exploration vessel offshore Guyana to operate in parallel to the Stena Carron to explore the block’s prospects. The addition will bring the company’s total number of drillships on the Stabroek Block to three.

The Noble Bob Douglas is completing initial stages of development drilling for Liza Phase 1, for which ExxonMobil announced a funding decision in 2017 (OGJ Online, June 16, 2017). Phase 1 will consist of 17 wells connected to a floating production, storage, and offloading vessel designed to produce as much as 120,000 b/d of oil (OGJ Online, June. 12, 2018). The start of oil production is expected in early 2020. Phase 2 concepts are similar to Phase 1 and involve a second FPSO with production capacity of 220,000 b/d. A third development, Payara, is planned to follow Liza Phase 2.

Esso E&P Guyana is operator and holds a 45% interest in the Stabroek block. Hess Guyana Exploration Ltd. holds 30% interest and CNOOC Nexen Petroleum Guyana Ltd. holds 25% interest.