ExxonMobil has made a sixth oil discovery on Guyana's deepwater Stabroek block
The latest find was made in the Ranger-1 well that was spudded on 5 November 2017, and which "encountered around 230ft (70m) of high-quality, oil-bearing carbonate reservoir," ExxonMobil said.
The well was drilled to 21,161ft in 8,973ft of water.
ExxonMobil operates 6.6mn acre (26,800km2) Stabroek with a 45pc stake. US independent Hess holds 30pc, and the remaining 25pc belongs to Chinese state-owned CNOOC unit Nexen.
ExxonMobil's string of successful wells in Guyana started in May 2015, when it discovered more than 1bn bl of oil equivalent, featuring 32°API crude, at its Liza-1 well on Stabroek about 130mi offshore.
Guyana currently produces no hydrocarbons, and imports refined products from Trinidad and Tobago and the US to meet demand of about 12,800 b/d.
ExxonMobil will start production from its Stabroek wells in March 2020, the company's Guyana country manager Rod Henson said on 28 December 2017, adding that initial output will represent "only a fraction" of the the block's potential.
"It will be somewhere between 100,000 b/d and 120,000 b/d, and we will continue to try to accelerate on that."
Guyana anticipates offshore oil production of about 320,000 b/d by 2025, government officials in the sparsely populated South American country told Argus in October 2017.
"The Ranger-1 well discovery adds to previous world-class discoveries at Liza, Payara, Snoek, Liza Deep and Turbot, which are estimated to total more than 3.2bn recoverable oil-equivalent barrels" ExxonMobil said.
Ranger-1 was worked by the Stena Carron drillship that is moving to the Pacora prospect near the Payara discovery, the company said.