The Upper Cretaceous play in the Guyana-Suriname Basin is entering a more mature phase following several years of exploration success, according to Westwood Global Energy Group’s latest State of Exploration 2026 insight.
Westwood said only 15 emerging play wells were drilled globally in 2025, with previously significant plays such as the Upper Cretaceous in the Guyana-Suriname Basin now maturing. The consultancy said frontier exploration is not replenishing the industry’s pipeline of new emerging plays quickly enough, even as demand for new oil and gas resources remains strong.
According to the report, 64 high-impact exploration wells were completed worldwide in 2025, a 17% decline from the previous year and the lowest annual total recorded since Westwood began tracking the data in 2008. Those wells delivered 4.8 billion barrels of oil equivalent in discovered resources, with a commercial success rate of 31%, slightly higher than in 2023 and 2024.
Westwood noted that Cretaceous plays continued to dominate global exploration between 2021 and 2025, accounting for 46% of primary exploration targets and 65% of discovered resources, equivalent to about 18.8 billion barrels of oil equivalent. Lower Cretaceous reservoirs delivered the largest discoveries during the five-year period.
The consultancy also found that many of the industry’s newest plays are becoming smaller and offering fewer follow-up opportunities. Of the 38 new plays opened over the past 15 years, only eight have exceeded one billion barrels of oil equivalent. More than half contained over 90% of their estimated resources within the initial discovery, limiting the scope for additional large finds.
Westwood said the combination of fewer emerging plays, smaller discovery sizes and limited follow-on opportunities highlights the need for continued frontier exploration to replenish the industry’s portfolio of future discoveries
OilNOW highlighted the findings in its coverage of the report, noting that the consultancy considers Guyana-Suriname Upper Cretaceous play was identified as one of the established exploration plays now entering a more mature stage.