Prominence Energy Confirms Hydrogen, Helium and Methane in Initial Soil Gas Survey at PEL 803

Prominence Energy has reported initial results from a soil gas survey across its PEL 803 licence area on South Australia’s Eyre Peninsula, confirming the presence of hydrogen, helium and methane in near-surface measurements. The survey identified hydrogen concentrations up to 1,105 ppm, helium up to 36 ppm (more than seven times atmospheric background), and methane up to 5,000 ppm, providing early-stage validation of an active subsurface gas system. 

The results are significant in that they demonstrate consistent multi-gas anomalies across the licence area, supporting the company’s geological model and indicating the presence of a working system with identifiable source, migration and potential accumulation components. The co-occurrence of hydrogen, helium and methane, combined with their spatial relationship to key geological features, suggests that the observed surface signals may be linked to deeper subsurface accumulations. 

Helium anomalies appear to correlate with interpreted Hiltaba Granite bodies, pointing to a radiogenic source associated with uranium- and thorium-rich basement rocks. Hydrogen anomalies, by contrast, align with major structural lineaments interpreted from magnetic data, supporting a structurally controlled migration model where basement-rooted faults act as conduits for vertical gas movement. Methane concentrations are associated with thicker sedimentary sections and gravity highs, indicating an additional sedimentary component within the broader system. 

In addition to discrete sampling, Prominence deployed autonomous monitoring devices to capture temporal variations in gas concentrations. At one monitoring point, hydrogen levels increased rapidly after installation, declined, and then rose again, displaying cyclic behaviour consistent with active and continuously recharging seepage rather than isolated or artefactual readings. This repeatable recharge signal, observed even under conditions of high soil moisture that typically suppress gas migration, provides further support for an ongoing subsurface source. 

Full press release can be found here.