Field development update boosts Rex’s reserves estimate off Oman

Singapore’s Rex International Holding Limited has disclosed the results of an updated independent summary qualified person’s report (QPR) for its field offshore Oman.

The report for the Yumna field in Block 50 off the coast of Oman has been prepared by Exceed Torridon as part of Rex’s obligations to disclose its reserves and resources.

It represents an update to several in-house summary QPRs and independent QPRs, taking into account updates to the model that was used to provide, together with production forecasts, an estimate of the remaining reserves under various development options as of December 31, 2024.

The model in this independent summary QPR now includes further development wells that have been added in the plan to drain the Yumna field more effectively. 

Rex’s subsidiary, Masirah Oil Limited, is the sole owner of the Block 50 concession. The Singaporean player holds an 87.5% interest in Masirah following last year’s restructuring.

The Yumna field has five wells, the oil from which is processed at a mobile offshore production unit (MOPU). As of December 31, 2024, the field had produced around 9 million stock tank barrels (MMstb). According to Masirah, the field’s production rate is being regularly optimized to maximize recovery.

Based on the latest report, Masirah’s net entitlement volume in base 2P reserves has increased by 27% (from 3.7 to 4.7 MMstb), coupled with a 34% increase in high 3P reserves, from 4.1 to 5.5 MMstb. As stated by Rex, whose net entitlement volume has seen the same increase due to its shareholding in Masirah, these changes reflect the optimization of the depletion plan.

Block 50 is an approximately 17,000 square-kilometer offshore concession located in the Gulf of Masirah, east of Oman. It achieved its first oil in February 2020, while the approval of the field development plan for the Yumna Field and declaration of commerciality (DOC) were obtained in July 2020.

In June 2024, Masirah wrapped up a multi-well drilling program at the field, which started in late March. Northern Offshore’s Energy Emerger jack-up rig was used to get the job done, which included a new in-field well and the work-over of two existing production wells.

According to Rex’s subsidiary, its plans for this year entail continuing to optimize production facilities and well operations, including the installation of a second flowline connecting the MOPU to the floating storage and offloading (FSO) unit to enhance the reliability of the production system. Additionally, the company intends to start a farm-out exercise in collaboration with Gneiss.