oa Soil Gas Mapping for Hydrogen Targeting – Case Study from Poland

Natural hydrogen, often referred to as “white hydrogen,” is gaining attention as a potential zero-emission energy source. This hydrogen is generated through various natural processes, such as serpentinization, radiolysis or biological activity of microorganisms. To obtain the most reliable prediction of hydrogen resources, the research should combine geological, geochemical, and geophysical data analysis, accompanied by laboratory tests and fieldwork. However, without clearly established exploration guidelines, the direct detection of hydrogen surface emanations remains one of the most straightforward pathfinders. Here, we present the preliminary results of soil gas studies focused on ²²²Rn content and molecular composition, dedicated to hydrogen exploration. Two potential fairy circle structures in E Poland were selected based on LiDAR data. ²²²Rn contents show that potential pathways of gas migration to the surface occur not in the fairy circle structure itself, but at the boundary and in its proximity. Molecular composition analyses of the soil gas reveal elevated methane and carbon dioxide contents. Hydrogen contents differentiate the two structures. Hydrogen occurs in only two samples at low concentrations in one of the structures, while for the second one, it was identified in four samples at markedly higher concentrations, ranging from 108 to 314 ppm.