Yumna Field’s Rising Reserves: Key Insights for Investors and Businesses in Oman’s Block 50
Masirah Oil Limited (MOL), operator of Block 50—the only producing license off Oman’s east coast—has announced a significant increase in its reserves potential for the flagship Yumna Field.
According to a recent Qualified Person’s Report from February, Rex International Holding, MOL’s majority shareholder, estimates the remaining gross 2P (proved + probable) reserves at 7.2 million stock tank barrels (MMstb). This estimate is based on anticipated output from existing wells, along with plans to drill three additional development wells in 2026. These initiatives are projected to improve the recovery factor to 55% before the field reaches its economic cut-off, projected for 2030.
As a result, the estimated ultimate recovery (EUR) from the Yumna Field has been adjusted to 16.8 MMstb at the 2P level, marking a 75% increase from the original estimate of 9.6 MMstb in 2020. Rex International highlighted this significant revision in its 2025 Annual Report, indicating an extended productive life for the field through ongoing development.
Singapore-based Rex International, a multinational oil and gas exploration entity, holds an effective indirect interest of 87.5% in MOL, which, in turn, owns 100% of the Block 50 license—an offshore concession covering approximately 17,000 sq km in the Gulf of Masirah.
In 2025, Yumna Field’s hydrocarbon output decreased to around 0.6 MMstb, down from 0.864 MMstb in 2024. By December 31, 2025, the field had produced approximately 9.6 MMstb since the Declaration of Commerciality was granted by the Ministry of Energy and Minerals in July 2020, enabling full-scale development. Five production wells were drilled between 2020 and 2024, contributing to the field’s output.
Additionally, in 2025, MOL enhanced system reliability by installing a second flowline to connect the Mobile Offshore Production Unit (MOPU) to the Floating Storage and Offloading (FSO) unit, which was swapped out to improve cost efficiency.
During the same year, MOL collaborated with Gneiss Energy and subsurface teams on a farm-out initiative for Block 50. Although no farm-out agreements were finalized, MOL gained valuable insights that will refine its future exploration and development strategies.
Earlier this year, Rex Oman Ltd, MOL’s parent company, contracted the Energy Emerger jack-up drilling rig to drill three development wells in the first half of 2026, aimed at maintaining production levels. To finance this project, Jasmine Energy Ltd, where MOL maintains an 87.5% subsidiary interest, successfully raised $25 million in senior secured bonds with a three-year term.
Looking ahead, MOL intends to continue optimizing production facilities and well operations while exploring further opportunities within Block 50.
Special Analysis by Omanet | Navigate Oman’s Market
Masirah Oil Limited’s recent report on the Yumna Field indicates significant upside potential for hydrocarbon production in Oman, now estimated to yield 16.8 million stock tank barrels, an increase of 75%. This development opens up strategic opportunities for businesses in the energy sector, particularly for those involved in drilling and infrastructure, while also underscoring the risks associated with fluctuating output and reliance on future drilling success. Smart investors should consider the implications of extended resource life and the upcoming exploration initiatives as they position themselves within a potentially lucrative but evolving market landscape.
