Australian energy company TMK Energy is inching closer to achieving commercial gas flow rates at its significant Gurvantes XXXV coal seam gas project located in Mongolia's South Gobi Desert.
Pressure Decline Signals Progress
The company's latest four-day pressure build-up test at the LF-06 pilot well has demonstrated continued reservoir pressure decline in the upper coal seams, moving steadily toward the critical gas desorption point. This development aligns perfectly with TMK's updated reservoir simulation modelling, indicating the project is progressing as planned.
The depressurisation process, achieved by pumping approximately 500 barrels of water daily from the coal seams, is fundamental to unlocking coal seam gas resources. As water is removed, reservoir pressure decreases, bringing the system closer to the moment when methane gas begins to separate from the coal matrix and flow at commercially viable rates.
Technical Validation and Gas Shows
Recent analysis has confirmed that the majority of produced water originates directly from the coal seams rather than adjacent aquifers or non-coal bearing zones. This provides strong evidence of good coal seam permeability, a crucial factor for successful coal seam gas extraction.
Bottom-hole pressure readings from the pilot well closely match simulated models based on Langmuir curves derived from core samples taken during the company's 2022 Snow Leopard-2 exploration well. These curves measure gas storage capacity in coal at varying pressures, with coal retaining gas similarly to how a sponge holds water - more pressure means more trapped gas.
The pressure decline has coincided with increased gas shows, indicating the reservoir is responding as anticipated. While significant gas production won't commence until reaching the actual desorption point, these early signs confirm the reservoir is behaving as expected.
Strategic Importance and Project Scale
TMK Energy's Chief Executive Officer Dougal Ferguson expressed satisfaction with the alignment between technical work and measured pressure decline. The Gurvantes XXXV project represents a potential first mover in Mongolia's energy sector, a country better known for copper and coal mining than gas production.
The project spans an enormous 8,400-square-kilometre area in the South Gobi Desert, positioned strategically less than 50 kilometres from China's Shivee Khuren border crossing and close to existing Chinese gas infrastructure. This location offers significant advantages for potential export opportunities.
Gurvantes XXXV hosts substantial gas resources, including 1.2 trillion cubic feet (Tcf) of 2C contingent resource and 5.3 Tcf of prospective gas. The region's extensive coal deposits create ideal conditions for coal seam gas production.
TMK has drilled seven operational wells at its Lucky Fox pilot project within the broader Gurvantes area and has been progressively increasing production activities since the beginning of the year. With pressure declining, gas shows increasing, and field results matching predictions, the company appears poised for a commercial breakthrough that could transform the promising coal basin into a legitimate gas province.
