CGX Energy’s Wei-1 well offshore Guyana was identified in 2023 as a key test of whether oil discoveries outside the Stabroek Block could support a second standalone development.
The well was drilled in the Corentyne Block following the Kawa-1 discovery in February 2022, which marked CGX’s first major find in more than 20 years and pointed to additional prospectivity in the block.
CGX shifted its focus to Wei-1 after analyzing Kawa-1 data. The company said the findings increased the prospect’s chance of success from 29% to 56%.
To fund the campaign, CGX secured a US$35 million loan from Frontera Energy Corporation, using its assets as collateral. The arrangement resulted in Frontera increasing its participating interest to 68%, while CGX held 32%.
Wei-1 was flagged as a high-impact well by both Westwood and Rystad Energy ahead of drilling.
Operations faced delays. The setbacks prompted Guyana to tighten contract enforcement to ensure work programs are completed within agreed timelines.
CGX and Frontera announced in July 2023 that Wei-1 encountered 210 feet of hydrocarbon-bearing sands in the Santonian interval. The companies said wireline logs and core samples were collected, but oil samples were not retrieved due to tool failure.
Final results released in November 2023 confirmed 13 feet of net pay in the Maastrichtian, 61 feet in the Campanian, and 40 feet in the Santonian.
CGX stated that the Maastrichtian interval contained medium sweet crude at 24.9 API, comparable to crude produced at the Liza development.
CGX may drill more wells at Corentyne Block after Wei-1 | OilNOW
Data from Kawa-1 and Wei-1 indicated a combined 81 feet of net pay in the Maastrichtian, with estimated recoverable resources between 514 and 628 million barrels of oil equivalent. Additional drilling was required to determine commercial viability.
CGX’s financial position weakened during this period. By March 2023, the company had sold more than 76% of its common shares to Frontera, giving the partner voting control.
The companies did not advance development within the license period. The Government of Guyana determined that work commitments were not met and the Corentyne Block license expired on June 28, 2024.
CGX and Frontera rejected that position. The companies stated their rights “remain valid and enforceable under the Petroleum Agreement” and indicated they were prepared to pursue legal action if discussions fail.
The Corentyne Block had been viewed as Guyana’s most prospective area outside the Stabroek Block, but Wei-1 did not progress to underpin the country’s second offshore story.
