AIM-listed Mosman Oil and Gas, the helium, hydrogen, and hydrocarbon exploration, development, and production company, has provided an update on the Sagebrush helium project in Colorado, USA, where it holds an 82.5% working interest.
Engagement of Sproule for Independent Resource Estimate
Mosman has engaged Sproule Incorporated, a globally recognised independent energy consulting firm, to provide an independent estimate of helium resources for the Sagebrush project. This engagement follows the Company's internal assessments and the announcement on 8 May 2025 of maiden contingent resources based on a report from Four Corners Helium LLC (FCH) dated 5 May 2025. The FCH report estimated:
• 205 million cubic feet (mmcf) of net helium contingent resources (C2 Best Estimate, after 18.67% royalty and Mosman's 82.5% working interest), and
• 1.683 billion cubic feet (bcf) of net hydrocarbon contingent resources (based on an initial gas in place of 18.4 bcf and recoverable gas of 11 bcf).
Sproule's scope of work includes a comprehensive review of geological and engineering data, including historic gas sample analyses from the Sagebrush-1 well, which indicated a gas composition of 2.76% helium, 19.5% methane, and other gases. The independent assessment is expected to provide estimates of both contingent and prospective helium resources, further validating and refining Mosman's internal estimates to support future development and commercialisation efforts. Mosman will provide further updates upon receipt of Sproule's report.
3D Seismic Survey
The Company intends to commence a 3D seismic survey over the Sagebrush project area this quarter. This seismic program, which is expected to cover approximately 16 square miles, will provide detailed subsurface mapping, enabling Mosman to better define high-potential drilling targets. The acquisition of 3D seismic data is a critical step in de-risking the Project and optimising the planning of future exploration and development activities.
Extended Production Test of Sagebrush-1 Well
Mosman is also advancing technical planning for a 4 to 6 week extended production test of the Sagebrush-1 Leadville Formation at various intervals from 7200' to approximately 7400'. It was from this formation that the DST and gas sample were taken. The extended production test, which is targeted for the fourth quarter of 2025, will provide valuable data on the wells production potential, particularly for helium and associated hydrocarbons, and will assist in assessing the commercial viability of the Project. Before the extended production test can begin, several prerequisites must be completed, including the finalising of bonding arrangements and completion of the transfer of ownership of the Project.
These planned operations at Sagebrush will be funded from the Company's existing cash resources.
Mosman Interim-CEO Howard Mclaughlin, commented: 'Engaging Sproule, acquiring the 3D seismic survey, and advancing the extended production test at Sagebrush-1 are pivotal steps in our helium strategy. These initiatives are designed to validate our resource estimates, de-risk the project, and provide the data needed to advance towards commercialisation. We are committed to executing these plans efficiently and safely, with the goal of unlocking the full potential of the Sagebrush project.'
Source: Mosman Oil and Gas
